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Dutta N, Mitra S, Nirmalkar N. Understanding the Role of Surface Charge on Nanobubble Capillary Bridging during Particle-Particle Interaction. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:4475-4488. [PMID: 38356240 DOI: 10.1021/acs.langmuir.3c03963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/16/2024]
Abstract
The interactions between particles due to long-range hydrophobic forces have been extensively investigated. The hydrophobic force is likely a capillary force that arises from the formation of capillary bridges due to the merging of nanobubbles. In this study, we aim to investigate the impact of the nanobubble surface charge on the capillary bridge and, subsequently, the interaction between particles. The surface charge of the nanobubbles was altered in the presence of various surfactants (cationic, anionic, and nonionic) and salts (mono-, di-, and trivalent). The particle-particle interaction was quantified by measuring the aggregate size of the hydrophobized glass particles. Both experimental and theoretical findings confirm that the interaction between particles was enhanced when the surface potential of the nanobubble was around the neutral regime. This is probably because, when the surface potential was close to neutral, the interaction between two surface-deposited nanobubbles dominated over electrostatic repulsion, which was more conducive to the formation of the nanobubble capillary bridge. The estimation of the constrained Gibbs potential also showed the capillary bridge to be more stable when surface charge density along the bridge gas-liquid interface was minimal.
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Affiliation(s)
- Nilanjan Dutta
- Department of Chemical Engineering, Indian Institute of Technology Ropar, Punjab 140001, India
| | - Subhasish Mitra
- ARC Center of Excellence for Enabling Eco-efficient Beneficiation of Minerals, School of Engineering, The University of Newcastle, New South Wales 2308, Australia
| | - Neelkanth Nirmalkar
- Department of Chemical Engineering, Indian Institute of Technology Ropar, Punjab 140001, India
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2
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Zhou W, Liu X, Long Y, Xie G, Chen Y. Monitoring effects of hydrodynamic cavitation pretreatment of sodium oleate on the aggregation of fine diaspore particles through small-angle laser scattering. ULTRASONICS SONOCHEMISTRY 2023; 100:106574. [PMID: 37734167 PMCID: PMC10514452 DOI: 10.1016/j.ultsonch.2023.106574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 08/11/2023] [Accepted: 08/29/2023] [Indexed: 09/23/2023]
Abstract
Hydrodynamic cavitation (HC) enhanced fine particle aggregation could be largely due to the generation of tiny bubbles and their role in bridging particles. However, the lack of adequate characterizations of aggregates severally limits our further understanding of the associated aggregation behaviors. In this study, the aggregation of fine diaspore particles was comparatively investigated in sodium oleate (NaOl) solutions with and without HC pretreatment through the small-angle laser scattering (SALS) technique in a shear-induced aggregation (SIA) system. Results showed that HC pretreatment caused the formation of bulk nanobubbles (BNBs), which significantly modified the particle interactions and thereby modified the size and mass fractal dimension (Df) of aggregates under different SIA conditions. Although HC pretreatment did not noticeably alter the gradual change trend of aggregate size and structure characteristics under specific variables, BNBs bridging facilitated the aggregation process towards the diffusion-limited cluster aggregation model, resulting in the formation of larger but looser aggregates. This effect was more pronounced under relatively high NaOl concentrations. Apart from BNBs, the aggregation was also affected by cavitation bubbles formed during shear cavitation, which was more significant under high stirring intensity conditions (i.e., 1800 rpm) than the low stirring intensity conditions (i.e., 600 rpm).
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Affiliation(s)
- Weiguang Zhou
- Key Laboratory of Coal Processing and Efficient Utilization of Ministry of Education, School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou 221116, PR China; Yunnan Key Laboratory of Green Separation and Enrichment of Strategic Metal Mineral Resources, Kunming University of Science and Technology, Kunming 650093, PR China
| | - Xinran Liu
- Key Laboratory of Coal Processing and Efficient Utilization of Ministry of Education, School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou 221116, PR China
| | - Yufeng Long
- Key Laboratory of Coal Processing and Efficient Utilization of Ministry of Education, School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou 221116, PR China
| | - Guangyuan Xie
- Key Laboratory of Coal Processing and Efficient Utilization of Ministry of Education, School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou 221116, PR China.
| | - Yanfei Chen
- School of Metallurgy and Environment, Central South University, Changsha 410083, PR China.
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3
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Bird E, Liang Z. Nanobubble-Induced Aggregation of Ultrafine Particles: A Molecular Dynamics Study. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023. [PMID: 37399536 DOI: 10.1021/acs.langmuir.3c00787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/05/2023]
Abstract
Nanobubble-induced aggregation (NBIA) of fine and ultrafine particles in liquid is a promising method for enhancing floatation rates in mineral processing, cleaning contaminants from water, and reviving marine ecosystems. Although the current experimental techniques can measure the nanobubble capillary force between two surfaces with controlled approach speed, they are not capable of imaging NBIA dynamics of fine/ultrafine particles by real-time observation with nanoscale spatial resolution. In this work, we use molecular dynamics (MD) simulations to study dynamics of NBIA of Ag particles in a Lennard-Jones fluid system. The molecular-level modeling allows us to study microscopic details of NBIA dynamics that are inaccessible by current experimental means. Using MD simulations, we investigated the effects of NB size, surface wettability, surface roughness, and contact line pinning on NBIA dynamics. Our modeling results show that both concave NB bridges between two hydrophobic surfaces and convex NB bridges between two hydrophilic surfaces can result in an attractive nanobubble capillary force (NBCF) that causes the aggregation of Ag particles in liquids. The equilibrium separation between two fully aggregated particles can be well predicted by the improved capillary force model. We also observe that the change of contact angle after the contact line pinning occurs at the sharp edge of a particle, which slows the aggregation process. Our thermodynamics analysis shows that there is a critical contact angle below which the merged surface NBs will detach from the surface instead of causing aggregation. The prediction of the critical contact angle is corroborated by our MD simulation results.
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Affiliation(s)
- Eric Bird
- Department of Mechanical and Aerospace Engineering, Missouri University of Science and Technology, Rolla, Missouri 65409, United States
| | - Zhi Liang
- Department of Mechanical and Aerospace Engineering, Missouri University of Science and Technology, Rolla, Missouri 65409, United States
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4
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Min Oo Y, Somnuk K. Investigation of free fatty acid reduction from mixed crude palm oil using 3D-printed rotor-stator hydrodynamic cavitation: An experimental study of geometric characteristics of the inner hole. ULTRASONICS SONOCHEMISTRY 2023; 98:106472. [PMID: 37348259 PMCID: PMC10314289 DOI: 10.1016/j.ultsonch.2023.106472] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 05/22/2023] [Accepted: 06/06/2023] [Indexed: 06/24/2023]
Abstract
A continuous esterification process is employed to decrease the free fatty acid (FFA) concentration of FFA-rich mixed crude palm oil. Both optimal and recommended conditions are determined for the esterification reaction conditions and the geometry of the 3D-printed rotor design in the rotor-stator hydrodynamic cavitation reactor. This study is primarily concerned with the effect of the cavitation device configuration, especially the rotor design, on FFA reduction. Instead of conventional spherical or cylindrical drilled holes, a point angle cone-shaped hole is used to create cavities over the rotor surface. These point angles are adjusted to clarify their effect on FFA reduction. The response surface methodology is applied to determine the optimal concentrations of methanol and sulfuric acid, rotor speed, hole diameter and depth, and cone point angle. The recommended conditions are 20.8 wt% methanol, 2.6 wt% sulfuric acid, 3000 rpm, 5 mm hole diameter, 5 mm hole depth, and 110°, respectively. Under this configuration, the FFA content is reduced from 12.014 wt% to around 1 wt%. A maximum yield of 97.34 vol% esterified oil is obtained through a completed phase separation step, and 93.31 vol% pure oil is collected after the cleansing step. The recommended conditions result in reduced chemical usage, cheaper FFA reduction, and lower environmental impact. This creative rotor design effectively improves our understanding of the geometry of the cavitation device, thus enhancing the cavitation effect in industrial operations.
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Affiliation(s)
- Ye Min Oo
- Department of Mechanical and Mechatronics Engineering, Faculty of Engineering, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand
| | - Krit Somnuk
- Department of Mechanical and Mechatronics Engineering, Faculty of Engineering, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand; Energy Technology Research Center, Faculty of Engineering, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand.
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5
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Ozkan A, Esmeli K. Use of ultrasonic treatment as a pre-phase in the shear flocculation process. ULTRASONICS 2023; 134:107052. [PMID: 37295220 DOI: 10.1016/j.ultras.2023.107052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 03/04/2023] [Accepted: 05/23/2023] [Indexed: 06/12/2023]
Abstract
The use of ultrasonic energy has mostly been investigated for the flotation process in mineral processing, but its application to flocculation with collectors is extremely limited. Therefore, in this study, the effect of ultrasound in the shear flocculation technique, was intended to be revealed by using a celestite sample. The initial studies carried out for this purpose showed that in the absence of any reagent, the ultrasonication decreased the surface charge of the mineral, which caused the coagulation of the celestite suspension. In this scope, the short application of ultrasound at high power (i.e., 2 min batch regime and 150 W) provided a more positive effect. In the flocculation process carried out with collectors, the use of ultrasonic energy as a pre-phase for the suspension enhanced the aggregation of celestite particles. This result also fits well with the rise in the contact angle and the decrease in the zeta potential of the mineral due to the ultrasound. However, when the ultrasound was applied directly to the flocculation phase (ultrasound-induced flocculation only), the aggregation of celestite particles was affected adversely. Consequently, it can be said that in the shear flocculation process, the ultrasonic treatment should be used as a pre-phase for mineral suspensions. In this case, the flocculation of fine mineral particles in suspensions with surfactants can be improved by ultrasonic processing.
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Affiliation(s)
- Alper Ozkan
- Department of Mining Engineering, Konya Technical University, Konya, Turkey
| | - Kiraz Esmeli
- Department of Mining Engineering, Konya Technical University, Konya, Turkey.
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Jin S, Shi Q, Ou L. Hydrophobic Flocculation of Fine Cassiterite Using Alkyl Hydroxamic Acids with Different Carbon Chain Lengths as Collectors. Molecules 2023; 28:molecules28093911. [PMID: 37175321 PMCID: PMC10179750 DOI: 10.3390/molecules28093911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 04/28/2023] [Accepted: 05/03/2023] [Indexed: 05/15/2023] Open
Abstract
This work investigated the hydrophobic flocculation of cassiterite using four alkyl hydroxamic acids with varying carbon chain lengths, i.e., hexyl hydroxamate (C6), octyl hydroxamate (C8), decyl hydroxamate (C10) and dodecyl hydroxamate (C12), as collectors. Microflotation tests were performed to investigate the flotation behaviour of cassiterite in the presence of the four alkyl hydroxamic acids. Focused beam reflectance measurement (FBRM) and a particle video microscope (PVM) were used to analyse and monitor the real-time evolution of the particle size distribution of cassiterite and the images of flocs during flocculation. The extended DLVO theory interaction energies between the cassiterite particles were calculated on the basis of the measured contact angle and the zeta potential of cassiterite to determine the aggregation and dispersion behaviour of the cassiterite particles. The microflotation test results suggested that the floatability of cassiterite improved with the increase in the carbon chain length of hydroxamates. FBRM, PVM images and extended DLVO theory calculation results indicated that when C6 was used as the collector, the cassiterite particles could not form hydrophobic flocs because the total potential energy between them was repulsive. When C8, C10 and C12 were used as collectors, the energy barrier amongst particles decreased with increasing hydroxamate concentration. The lowest concentrations of C8, C10 and C12 that could cause the hydrophobic aggregation of cassiterite were approximately 1 × 10-3, 1 × 10-4 and 2 × 10-5 mol/L, respectively. The aggregation growth rate and apparent floc size increased with an increasing collector concentration. Hydroxamic acid with a longer carbon chain could induce the cassiterite particles to form larger flocs at a lower concentration in a shorter time.
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Affiliation(s)
- Saizhen Jin
- School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China
| | - Qing Shi
- School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China
| | - Leming Ou
- School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China
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7
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Chongliang T, Fangyuan M, Tingyu W, Di Z, Ye W, Mingjiao L, Xiangwei L, Xinyue L. Study on surface physical and chemical mechanism of nanobubble enhanced flotation of fine graphite. J IND ENG CHEM 2023. [DOI: 10.1016/j.jiec.2023.02.039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/06/2023]
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8
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Zhang D, Ma F, Tao Y. Study on effect of nanobubble on ultra-fine flake graphite (UFG) flotation. PARTICULATE SCIENCE AND TECHNOLOGY 2023. [DOI: 10.1080/02726351.2023.2173110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- Di Zhang
- School of Mining Engineering, University of Science & Technology Liaoning, Anshan, Liaoning, China
| | - Fangyuan Ma
- School of Mining Engineering, University of Science & Technology Liaoning, Anshan, Liaoning, China
| | - Youjun Tao
- School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou, China
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9
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Wang R, Sun W, Han H, Sun W, Liu R. A novel fine gangue depressant: Metal ions-starch colloidal depressant and its effect on ultrafine chlorite. Colloids Surf A Physicochem Eng Asp 2022. [DOI: 10.1016/j.colsurfa.2022.130326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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10
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Bhukya J, Mohapatra D, Naik R. Hydrodynamic cavitation processing of ascorbic acid treated precooled sugarcane juice for physiochemical, bioactive, enzyme stability, and microbial safety. J FOOD PROCESS ENG 2022. [DOI: 10.1111/jfpe.14209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- Jithender Bhukya
- Outreach campus PG School IARI ICAR‐Central Institute of Agricultural Engineering Bhopal India
| | - Debabandya Mohapatra
- Outreach campus PG School IARI ICAR‐Central Institute of Agricultural Engineering Bhopal India
| | - Ravindra Naik
- Regional Center, ICAR‐Central Institute of Agricultural Engineering Coimbatore India
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11
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Ma F, Tao D. A Study of Mechanisms of Nanobubble-Enhanced Flotation of Graphite. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:3361. [PMID: 36234489 PMCID: PMC9565505 DOI: 10.3390/nano12193361] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 09/18/2022] [Accepted: 09/23/2022] [Indexed: 06/16/2023]
Abstract
This study was conducted to investigate the mechanisms of enhanced microfine flake graphite (MFG) flotation by nanobubbles generated based on the principle of hydrodynamic cavitation. The effects of nanobubbles on graphite surface properties were characterized in terms of the flotation kinetics, collector adsorption behavior, Zeta potential, IR spectra, contact angle, etc. The results show that the surface nanobubbles increased the hydrophobic attraction and reduced the electrostatic repulsion between the graphite particles and collector molecules, significantly improving the flotation selectivity and the kinetic flotation rate and promoting the agglomeration of MFG.
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Affiliation(s)
- Fangyuan Ma
- School of Mining Engineering, University of Science & Technology Liaoning, Anshan 114051, China
| | - Dongping Tao
- School of Resources and Environmental Engineering, Shandong University of Technology, Zibo 255049, China
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12
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Al-caustic starch coordination compounds: A new depressant for fine calcite. Colloids Surf A Physicochem Eng Asp 2022. [DOI: 10.1016/j.colsurfa.2022.129268] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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13
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Comparison of the Effects of Sodium Oleate and Benzohydroxamic Acid on Fine Scheelite and Cassiterite Hydrophobic Flocculation. MINERALS 2022. [DOI: 10.3390/min12060687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Sodium oleate (NaOL) and benzohydroxamic acid (BHA) are commonly used scheelite and cassiterite flotation collectors. Hydrophobic flocculation flotation of fine minerals has been extensively studied and reported under a NaOL system, but not under a BHA system. In this paper, the particle size distribution and flotation behaviour of fine scheelite (−10 μm) and cassiterite (−37 + 10 and −23 μm) after shear stirring in NaOL, BHA, and Pb2+ + BHA systems were studied by laser particle size analysis and flotation tests. The measured particle size distribution results revealed that the fine minerals could aggregate under a NaOL system, and the aggregate size increased with increasing stirring time and speed, with scheelite aggregating faster than cassiterite. BHA did not cause scheelite or cassiterite to form hydrophobic aggregates. At low stirrer speeds, the minerals could form small, weak, and easily broken aggregates when Pb2+ + BHA was added. The results of the flotation tests revealed that increasing the stirring time and speed increased the flotation rate and recovery when NaOL and BHA were added. When Pb2+ + BHA was added, however, the changes in flotation rate and recovery were not noticeable when the stirring conditions were changed.
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14
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Enhancement of selective fine particle flotation by microbubbles generated through hydrodynamic cavitation. POWDER TECHNOL 2022. [DOI: 10.1016/j.powtec.2022.117502] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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15
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Recent Developments in Generation, Detection and Application of Nanobubbles in Flotation. MINERALS 2022. [DOI: 10.3390/min12040462] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
This paper reviews recent developments in the fundamental understating of ultrafine (nano) bubbles (NBs) and presents technological advances and reagent types used for their generation in flotation. The generation of NBs using various approaches including ultrasonication, solvent exchange, temperature change, hydrodynamic cavitation, and electrolysis was assessed. Most importantly, restrictions and opportunities with respect to the detection of NBs were comprehensively reviewed, focusing on various characterization techniques such as the laser particle size analyzer (LPSA), nanoparticle tracking (NTA), dynamic light scattering (DLS), zeta-phase light scattering (ZPALS), and zeta sizer. As a key feature, types and possible mechanisms of surfactants applied to stabilize NBs were also explored. Furthermore, flotation-assisted nano-bubbles was reported as an efficient method for recovering minerals, with a special focus on flotation kinetics. It was found that most researchers reported the existence and formation of NBs by different techniques, but there is not enough information on an accurate measurement of their size distribution and their commonly used reagents. It was also recognized that a suitable method for generating NBs, at a high rate and with a low cost, remains a technical challenge in flotation. The application of hydrodynamic cavitation based on a venturi tube and using the LPSA and NTA in laboratory scales were identified as the most predominant approaches for the generation and detection of NBs, respectively. In this regard, neither pilot- nor industrial-scale case studies were found in the literature; they were only highlighted as future works. Although the NB-stabilizing effects of electrolytes have been well-explored, the mechanisms related to surfactants remain the issue of further investigation. The effectiveness of the NB-assisted flotation processes has been mostly addressed for single minerals, and only a few works have been reported for bulk materials. Finally, we believe that the current review paves the way for an appropriate selection of generating and detecting ultrafine bubbles and shines the light on a profound understanding of its effectiveness.
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Xu M, Li C, Zhang H, Kupka N, Peuker UA, Rudolph M. A contribution to exploring the importance of surface air nucleation in froth flotation – The effects of dissolved air on graphite flotation. Colloids Surf A Physicochem Eng Asp 2022. [DOI: 10.1016/j.colsurfa.2021.127866] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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17
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Wang X, Yuan S, Liu J, Zhu Y, Han Y. Nanobubble-enhanced flotation of ultrafine molybdenite and the associated mechanism. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2021.118312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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18
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Zhou S, Zhou W, Dong L, Peng Y, Xie G. Micellization Transformations of Sodium Oleate Induced by Gas Nucleation. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:9701-9710. [PMID: 34339198 DOI: 10.1021/acs.langmuir.1c01008] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The interfacial properties of surfactant solutions are closely related to the micellization of surfactants. Temperature, salt type and concentration, pH, and other parameters affecting the micellization of surfactants have all been extensively investigated previously. However, the effect of dissolved gas on surfactant micellization and associated interfacial properties' transformations is not completely understood yet. In this study, sodium oleate (NaOl) was chosen as the research object, and the role of gas/gas nucleation in NaOl micellization was systematically investigated. The results indicated that the solution changed to be more turbid and the dissolved oxygen content increased after NaOl solutions were subjected to compression-decompression treatments. Meanwhile, the surface tension of the NaOl solution was altered, which was more pronounced when the concentration of NaOl was close to the critical micelle concentration. Given that the surface tension was a good indicator of the assembly and distribution state of the soluble monomers and insoluble micelles of NaOl, interactions between nucleated bubbles originating from the gas nucleation and NaOl molecules were unveiled through the analysis of the size distribution and zeta potential of sub-micro- and nanoscale particles in bulk solutions. Finally, possible micellization models of NaOl molecules, fully considering the role of gas/gas nucleation, were proposed under varying NaOl concentration conditions.
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Affiliation(s)
- Shaoqi Zhou
- School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou, Jiangsu 221116, China
| | - Weiguang Zhou
- School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou, Jiangsu 221116, China
| | - Lisha Dong
- School of Chemical Engineering, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Yaoli Peng
- School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou, Jiangsu 221116, China
| | - Guangyuan Xie
- School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou, Jiangsu 221116, China
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19
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Zhang F, Sun L, Yang H, Gui X, Schönherr H, Kappl M, Cao Y, Xing Y. Recent advances for understanding the role of nanobubbles in particles flotation. Adv Colloid Interface Sci 2021; 291:102403. [PMID: 33780858 DOI: 10.1016/j.cis.2021.102403] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 03/15/2021] [Accepted: 03/16/2021] [Indexed: 12/01/2022]
Abstract
Traditional froth flotation is the primary method for the separation and upgrading of fine mineral particles. However, it is still difficult for micro-fine and low-quality minerals to effectively separate. It is generally believed that bubble miniaturization is of great significance to improve flotation efficiency. Due to their unique physical and chemical properties, the application of nanobubbles (NBs) in ore flotation and other fields has been widely investigated as an important means to solve the problems of fine particle separation. Therefore, a fundamental understanding of the effect of NBs on flotation is a prerequisite to adapt it for the treatment of fine and low-quality minerals for separation. In this paper, recent advances in the field of nanobubble (NB) formation, preparation and stability are reviewed. In particular, we highlight the latest progress in the role of NBs on particles flotation and focus in particular on the particle-particle and particle-bubble interaction. A discussion of the current knowledge gap and future directions is provided.
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Affiliation(s)
- Fanfan Zhang
- School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou 221116, Jiangsu, China
| | - Lijuan Sun
- School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou 221116, Jiangsu, China
| | - Haichang Yang
- School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou 221116, Jiangsu, China
| | - Xiahui Gui
- National Engineering Research Center of Coal Preparation and Purification, China University of Mining and Technology, Xuzhou 221116, Jiangsu, China
| | - Holger Schönherr
- Physical Chemistry I & Research Center of Micro and Nanochemistry and Engineering (Cμ), Department of Chemistry and Biology, University of Siegen, Adolf-Reichwein-Straße 2, Siegen 57076, Germany
| | - Michael Kappl
- Max Planck Institute for Polymer Research, Ackermannweg 10, Mainz 55128, Germany
| | - Yijun Cao
- National Engineering Research Center of Coal Preparation and Purification, China University of Mining and Technology, Xuzhou 221116, Jiangsu, China; School of Chemical Engineering and Technology, Zhengzhou University, Zhengzhou 450066, Henan, China).
| | - Yaowen Xing
- National Engineering Research Center of Coal Preparation and Purification, China University of Mining and Technology, Xuzhou 221116, Jiangsu, China.
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20
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Investigation of nanobubble enhanced reverse anionic flotation of hematite and associated mechanisms. POWDER TECHNOL 2021. [DOI: 10.1016/j.powtec.2020.10.040] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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21
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Zhou W, Liu L, Zhou B, Weng L, Li J, Liu C, Yang S, Wu C, Liu K. Electrokinetic potential reduction of fine particles induced by gas nucleation. ULTRASONICS SONOCHEMISTRY 2020; 67:105167. [PMID: 32442929 DOI: 10.1016/j.ultsonch.2020.105167] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 04/10/2020] [Accepted: 05/07/2020] [Indexed: 06/11/2023]
Abstract
Electrokinetic potential of particles has been extensively studied in colloidal systems over the past century, while up to date, the influence of gas on electrokinetic behaviors of particles has not been fully understood yet. In this study, the electrokinetic response of particles to gas nucleation was systematically investigated with coal as the object. The results showed that the nucleation of gas (both on particle surfaces and in water) significantly changed the particle' electrokinetic behaviors. Higher gas content and particle's surface hydrophobicity normally trigger more intensive gas nucleation, thus inducing more significant reduction of particle zeta potential. After gas nucleation, numerous nanobubbles (NBs) appear in the suspensions mainly in two forms: NBs adhering onto solid surfaces (ANBs) and NBs stagnating in bulk solutions (BNBs). ANBs not only enhance the surface heterogeneity, but also cause the "steric hindrance" effect, and electric double layer (EDL) overlapping and associated ions shielding towards charged particles, which significantly decrease their electrokinetic potentials. Although BNBs can also reduce the zeta potential of particles by EDL compressing, their functions are rather limited.
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Affiliation(s)
- Weiguang Zhou
- Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, China.
| | - Liming Liu
- School of Innovation and Entrepreneurship, Southern University of Science and Technology, Shenzhen 518055, China
| | - Baonan Zhou
- Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, China
| | - Li Weng
- Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, China; Clean Energy Institute, Academy for Advanced Interdisciplinary Studies, Southern University of Science and Technology, Shenzhen 518055, China
| | - Junguo Li
- Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, China; Clean Energy Institute, Academy for Advanced Interdisciplinary Studies, Southern University of Science and Technology, Shenzhen 518055, China
| | - Cheng Liu
- School of Resources and Environment Engineering, Wuhan University of Technology, Wuhan 430070, China
| | - Siyuan Yang
- School of Resources and Environment Engineering, Wuhan University of Technology, Wuhan 430070, China
| | - Changning Wu
- Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, China; Clean Energy Institute, Academy for Advanced Interdisciplinary Studies, Southern University of Science and Technology, Shenzhen 518055, China.
| | - Ke Liu
- Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, China; School of Innovation and Entrepreneurship, Southern University of Science and Technology, Shenzhen 518055, China; Clean Energy Institute, Academy for Advanced Interdisciplinary Studies, Southern University of Science and Technology, Shenzhen 518055, China.
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22
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Second Life Application of Automotive Catalysts: Hydrodynamic Cavitation Recovery and Photo Water Splitting. METALS 2020. [DOI: 10.3390/met10101307] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
A hydrodynamic cavitation method was used to maximize the effect of destructuration of a honeycomb monolithic support of a spent Selective Catalyst Reduction (SCR) catalyst—V2O5-WO3/TiO2-type—for extracting crystalline titanium and tungsten oxides from the cordierite surface. A high relative inlet pressure of 40 MPa was applied to a divergent nozzle for obtaining high shear stresses of the submerged cavitating jets and intensive micro- and nano-jets and shock waves acting on the particle surface of the milled catalyst. Scanning Electron Microscopy (SEM) analysis indicated the compact morphology of the thin metal oxide layer at the surface of the cordierite support and the high content of Ti and W elements in the sample. Energy dispersive spectroscopy (EDAX) performed along with TEM investigations on different nano-zones from the sample established the elemental composition of WO3-TiO2 agglomerates separated after hydrodynamic cavitation processing and identified as independent nanocrystalline structures through Bright Field Transmission Electron Microscopy (BF-TEM) and High Resolution Transmission Electron Microscopy (HR-TEM) measurements. The tetragonal anatase phase of TiO2 and cubic phase of WO3 were established by both interplanar d spacing measurements and X-ray diffraction analysis. The photoelectrochemical results showed the possible second life application of automotive catalysts.
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23
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Li P, Zhang M, Lei W, Yao W, Fan R. Effect of Nanobubbles on the Slime Coating of Kaolinite in Coal Flotation. ACS OMEGA 2020; 5:24773-24779. [PMID: 33015495 PMCID: PMC7528324 DOI: 10.1021/acsomega.0c03380] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 09/07/2020] [Indexed: 05/06/2023]
Abstract
Understanding the coating behavior of fine gangue slimes in the presence of nanobubbles (NBs) is important for the application of NB technology in flotation. In this study, slime coating of kaolinite in the flotation of a low-ash coal using deionized (DI) water and NB water was investigated. Kaolinite was found to depress coal flotation by the formation of coating on coal surfaces, but its deleterious effect was less pronounced in the NB water with mitigated slime coating. Setting tests, Brunauer-Emmett-Teller surface area measurements, and dynamic light scattering were conducted to understand the underpinning mechanism. In comparison with DI water, the degree of kaolinite aggregation was enhanced in the NB water. The intensified self-aggregation of kaolinite platelets which appears to be induced by the presence of NBs reduces the solid-liquid interfacial area as well as the number of free kaolinite particles in the suspension, mitigating the coating of kaolinite on coal surfaces in NB water flotation.
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Affiliation(s)
- Panwu Li
- College
of Resources and Environmental Engineering, Wuhan University of Science and Technology, Wuhan 430081, China
| | - Ming Zhang
- College
of Resources and Environmental Engineering, Wuhan University of Science and Technology, Wuhan 430081, China
- Hubei
Key Laboratory for Efficient Utilization and Agglomeration of Metallurgic
Mineral Resources, Wuhan 430081, China
| | - Wang Lei
- College
of Resources and Environmental Engineering, Wuhan University of Science and Technology, Wuhan 430081, China
| | - Wei Yao
- College
of Resources and Environmental Engineering, Wuhan University of Science and Technology, Wuhan 430081, China
| | - Rong Fan
- CSIRO
Mineral Resources, Private Bag 10, Clayton South, Victoria 3169, Australia
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24
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Zhou S, Wang X, Bu X, Wang M, An B, Shao H, Ni C, Peng Y, Xie G. A novel flotation technique combining carrier flotation and cavitation bubbles to enhance separation efficiency of ultra-fine particles. ULTRASONICS SONOCHEMISTRY 2020; 64:105005. [PMID: 32062426 DOI: 10.1016/j.ultsonch.2020.105005] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Revised: 02/06/2020] [Accepted: 02/06/2020] [Indexed: 05/06/2023]
Abstract
In this paper, a novel flotation technique that combines nano-scale bubbles generated by hydrodynamic cavitation (HC) and carrier flotation is proposed to promote the flotation efficiency of a high-ash (43%) ultra-fine coal sample (<45 µm). We investigated the mechanism by which cavitation bubbles enhance the separation efficiency of carrier flotation using focused beam reflectance measurements, polarizing microscopy, and extended Derjaguin-Landau-Verwey-Overbeek theory. The carrier particles (polystyrene (PS)) and fine coal were pre-treated in a venturi tube and then floated in a laboratory mechanical flotation cell. The flotation results indicate that the presence of cavitation bubbles significantly improved the carrier flotation performance of high-ash ultra-fine coal. This improvement was attributed to the presence of highly hydrophobic PS, which creates additional gas nuclei in the flotation system. The nano-bubbles, which were produced by the venturi tube and adhered to the fine coal particle surfaces, were conducive to the agglomeration of fine coal particles into large aggregates. Moreover, the nano-bubbles functioned as "bridges" of interaction between the carrier particles and large aggregates of fine coal particles. This paper mainly focused on the effect of carrier (PS) and HC on high-ash fine coal. The influence of different HC intensities on carrier (PS) flotation was discussed. Two models for the interactions between the coal particles, nano-bubbles, and PS during cavitation were proposed and were proved using the E-DLVO theory.
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Affiliation(s)
- Shaoqi Zhou
- Key Laboratory of Coal Processing and Efficient Utilization of Ministry of Education, School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou 221116, Jiangsu, China
| | - Xuexia Wang
- Key Laboratory of Coal Processing and Efficient Utilization of Ministry of Education, School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou 221116, Jiangsu, China
| | - Xiangning Bu
- Key Laboratory of Coal Processing and Efficient Utilization of Ministry of Education, School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou 221116, Jiangsu, China.
| | - Mengdie Wang
- Key Laboratory of Coal Processing and Efficient Utilization of Ministry of Education, School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou 221116, Jiangsu, China
| | - Bairui An
- Key Laboratory of Coal Processing and Efficient Utilization of Ministry of Education, School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou 221116, Jiangsu, China
| | - Huaizhi Shao
- Key Laboratory of Coal Processing and Efficient Utilization of Ministry of Education, School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou 221116, Jiangsu, China
| | - Chao Ni
- Key Laboratory of Coal Processing and Efficient Utilization of Ministry of Education, School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou 221116, Jiangsu, China
| | - Yaoli Peng
- Key Laboratory of Coal Processing and Efficient Utilization of Ministry of Education, School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou 221116, Jiangsu, China
| | - Guangyuan Xie
- Key Laboratory of Coal Processing and Efficient Utilization of Ministry of Education, School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou 221116, Jiangsu, China
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25
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Shi H, Li M, Liu Q, Nikrityuk P. Experimental and numerical study of cavitating particulate flows in a Venturi tube. Chem Eng Sci 2020. [DOI: 10.1016/j.ces.2020.115598] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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26
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Zhou W, Liu K, Wang L, Zhou B, Niu J, Ou L. The role of bulk micro-nanobubbles in reagent desorption and potential implication in flotation separation of highly hydrophobized minerals. ULTRASONICS SONOCHEMISTRY 2020; 64:104996. [PMID: 32050142 DOI: 10.1016/j.ultsonch.2020.104996] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Revised: 12/13/2019] [Accepted: 02/03/2020] [Indexed: 06/10/2023]
Abstract
Micro-nanobubbles (MNBs) generated during hydrodynamic cavitation (HC) have been extensively studied in mineral processing field in the past two decades. Many researchers have claimed that MNBs can effectively promote the collection of fine particles in flotation, while studies on MNBs assisted mineral separation are rare. In this study, the role of bulk MNBs in desorbing flotation reagent was investigated, with the aim of illustrating the potential effects of MNBs on minerals separation. The results showed that bulk MNBs could efficiently remove the sodium oleate (NaOl) from diaspore surfaces, reducing the residual concentration of NaOl on solids, which was more significant when the amount of NaOl pre-adsorbed was relatively small. Furthermore, lower residual concentration of NaOl on solids caused by MNBs cleaning made the particles less hydrophobic and flocs more friable. Given that gangue entrapment in flocs was one of the main limits for high-selective flotation, the roles of MNBs in enhancing reagent desorption and associated flocs breakup and reorganization probably contribute to higher separation efficiency of different minerals, which was confirmed by the flotation results of diaspore/kaolinite mixture.
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Affiliation(s)
- Weiguang Zhou
- School of Minerals Processing & Bioengineering, Central South University, Changsha 410083, China; Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, China
| | - Ke Liu
- Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, China
| | - Long Wang
- College of Mining Engineering, North China University of Science and Technology, Tangshan, China
| | - Baonan Zhou
- Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, China
| | - Jiaojiao Niu
- Simon F.S. Li Marine Science Laboratory, School of Life Science, Chinese University of Hong Kong, Hong Kong, China
| | - Leming Ou
- School of Minerals Processing & Bioengineering, Central South University, Changsha 410083, China.
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27
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Effect of Hydrodynamic Cavitation Assistance on Different Stages of Coal Flotation. MINERALS 2020. [DOI: 10.3390/min10030221] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
In this study, the effect of hydrodynamic cavitation (HC) on the conditioning stage (HCCS), separation stage (HCSS), and whole stage (HCWS) of coal flotation was investigated by flotation tests, laser granulometry, and contact angle measurements. The flotation results indicate that compared to conventional flotation, all HC-assisted flotation methods can improve concentrate combustible recovery and flotation constant rate. HCCS and HCSS show similar levels of improvement, while HCWS has a better flotation efficiency. The screening tests demonstrate that HC has the advantage of being able to liberate coarse coal particles (+0.25 mm) prior to being combined with gangues. On one hand, HC promotes the dispersion of both particles and agents, while longer cavitation time in HCCS does not lead to better flotation performance. On the other hand, enhancement of the adsorption of the collector on the surface of coal particles in HCCS is confirmed by flotation concentrate contact angle tests. However, HCSS leads to a decrease in concentrate hydrophobicity, compared to conventional flotation. The micro-nanobubbles generated by HC play an important role in improving flotation performance. HCWS offers the advantages of both HCCS and HCSS, and the cooperated mechanism of different HC modes enhances the recovery of coal particles in flotation.
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28
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The Interaction Force between Scheelite and Scheelite/Fluorite/Calcite Measured Using Atomic Force Microscopy. J CHEM-NY 2020. [DOI: 10.1155/2020/3163415] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The mechanism of the formation of the hydrophobic agglomerate in fine scheelite flotation was studied using zeta potential measurement, contact angle measurement, optical microscope measurement, and atomic force microscopy (AFM) colloid probe technology. Zeta potential measurement results confirmed the adsorption of sodium oleate on scheelite, fluorite, and calcite surface and surface potential difference at different pH values of ultrapure water. Contact angle measurement results confirmed the surface of nature scheelite, fluorite, and calcite was hydrophilic, and the surface after thread by sodium oleate solution was hydrophobic. The optical microscope measurement results confirmed the agglomerates could really form in ultrapure water of pH 8 or 10 and in 1 mM sodium oleate solution of pH 10. The agglomerations were empty and not tight in ultrapure water. On the contrary, the hydrophobic agglomerations were larger and denser after treated with sodium oleate solution than that of in ultrapure water. According to the AFM experiment results, the interaction forces on hydrophilic scheelite-scheelite and scheelite-fluorite were repulsive at pH 5.6 and attractive at pH 8 or 10. However, the interaction forces on hydrophilic scheelite-calcite were attractive at pH 5.6, 8 or 10. The interaction forces on hydrophobic scheelite-scheelite, scheelite-fluorite, and scheelite-calcite were attractive strongly due to the existence of hydrophobic force. The measurement results of the interaction forces were in good agreement with the changes of zeta potential and contact angle at different conditions. The combined results could be beneficial to understand the interaction force in fine scheelite flotation.
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29
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Shi H, Li M, Nikrityuk P, Liu Q. Experimental and numerical study of cavitation flows in venturi tubes: From CFD to an empirical model. Chem Eng Sci 2019. [DOI: 10.1016/j.ces.2019.07.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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30
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Role of mineral flotation technology in improving bitumen extraction from mined Athabasca oil sands—II. Flotation hydrodynamics of water‐based oil sand extraction. CAN J CHEM ENG 2019. [DOI: 10.1002/cjce.23598] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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31
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Rheological investigations on the hetero-coagulation between the fine fluorite and quartz under fluorite flotation-related conditions. POWDER TECHNOL 2019. [DOI: 10.1016/j.powtec.2019.06.019] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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32
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Xiao W, Zhao Y, Yang J, Ren Y, Yang W, Huang X, Zhang L. Effect of Sodium Oleate on the Adsorption Morphology and Mechanism of Nanobubbles on the Mica Surface. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:9239-9245. [PMID: 31268336 DOI: 10.1021/acs.langmuir.9b01384] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Nanobubbles promote the flotation of fine-grained minerals. In the associated mechanism, the aggregation of fine particles is first promoted, which increases the probability of collision between particles and bubbles. However, the interaction between nanobubbles and mineral particles is often neglected, especially when the surface properties of the nanobubbles are modified by flotation collectors. In this study, the interaction mechanism between nanobubbles and the mica surface is investigated by nanoparticle tracking analysis, zeta potential measurement, and atomic force microscopy. The results reveal that the hydrophobic group of sodium oleate points toward the inside of the nanobubble and the hydrophilic group faces outward after the interaction of sodium oleate molecules and nanobubbles. A surfactant micelle with nanobubbles as the core is formed, thus considerably reducing the concentration of sodium oleate to form micelles. The adsorption of the modified nanobubbles on the mineral surface is carried out by the specific adsorption of the exposed hydrophilic group and the mineral surface. This adsorption method is superior to the hydrophobic interaction between the nanobubbles and the hydrophobic mineral surface. Further, the nanobubbles are highly selective for the activation sites on the mineral surface in the adsorption mode. This study will help understand the interaction between nanobubbles and collectors to further apply nanobubbles to treat fine-grained mineral particles.
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Affiliation(s)
- Wei Xiao
- School of Resources Engineering , Xi'an University of Architecture and Technology , Xi'an 710055 , China
| | - Yulong Zhao
- School of Resources Engineering , Xi'an University of Architecture and Technology , Xi'an 710055 , China
| | - Juan Yang
- School of Resources Engineering , Xi'an University of Architecture and Technology , Xi'an 710055 , China
| | - Yaxin Ren
- School of Resources Engineering , Xi'an University of Architecture and Technology , Xi'an 710055 , China
| | - Wei Yang
- School of Resources Engineering , Xi'an University of Architecture and Technology , Xi'an 710055 , China
| | - Xiaotao Huang
- The Institute for Advanced Studies , Wuhan University , Wuhan 430072 , China
| | - Lijuan Zhang
- Shanghai Synchrotron Radiation Facility, Shanghai Advanced Research Institute , Chinese Academy of Sciences , Shanghai 201204 , China
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33
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Acoustic characterisation of pH dependant reversible micellar casein aggregation. Colloids Surf A Physicochem Eng Asp 2019. [DOI: 10.1016/j.colsurfa.2019.02.026] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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34
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35
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Zhou W, Niu J, Xiao W, Ou L. Adsorption of bulk nanobubbles on the chemically surface-modified muscovite minerals. ULTRASONICS SONOCHEMISTRY 2019; 51:31-39. [PMID: 30514483 DOI: 10.1016/j.ultsonch.2018.10.021] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 10/09/2018] [Accepted: 10/15/2018] [Indexed: 06/09/2023]
Abstract
Bulk nanobubbles (NBs) that are produced in the hydrodynamic cavitation (HC) process have been widely applied in mineral flotation for more than a decade, while how bulk NBs interact with minerals in the water-solid interface is still unclear. In this study, the adsorption behaviors of bulk NBs generated in the principle of HC on muscovite surfaces in the presence of dodecylamine (DDA) were investigated. The results show that NBs are likely coated with DDA in aqueous solutions. After attaching with muscovite, bulk NBs can adsorb on the mineral surfaces, probably following the three-contact line pinning theory. The adsorption of NBs increases the surface hydrophobicity of minerals, which can be inferred from the larger contact angles and the better flotation performances obtained in the presence of DDA/NBs. In addition, the adsorption of NBs is thought to be able to prevent the adsorption of DDA on the same space of the solid surfaces, which can be confirmed by the results of zeta potential measurements, contact angle measurements and AFM imaging results.
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Affiliation(s)
- Weiguang Zhou
- School of Minerals Processing & Bioengineering, Central South University, Changsha 410083, China; Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources, Central South University, Changsha 410083, China
| | - Jiaojiao Niu
- Simon F.S. Li Marine Science Laboratory, School of Life Science, Chinese University of Hong Kong, Hong Kong, China
| | - Wei Xiao
- School of Minerals Processing & Bioengineering, Central South University, Changsha 410083, China; Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources, Central South University, Changsha 410083, China
| | - Leming Ou
- School of Minerals Processing & Bioengineering, Central South University, Changsha 410083, China; Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources, Central South University, Changsha 410083, China.
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36
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Significant Improvement in the Scheelite Heating Flotation with Sodium Sulfide. MINERALS 2018. [DOI: 10.3390/min8120587] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
An efficiently optimized reagent regime was investigated to improve scheelite heating flotation. The scheelite grade and recovery in the plant were significantly improved by 5% and 6%, respectively, which remarkably augmented the economic profit by $260,000 per month. The interaction mechanisms of sodium sulfide and sodium oleate with scheelite, calcite and fluorite were evaluated by adsorption amount and Fourier transform infrared (FTIR) analyses. Sodium sulfide exhibited an excellent ability to promote the adsorption and desorption of sodium oleate on the scheelite surface and from the calcite and fluorite surfaces, thus facilitating the separation of scheelite from fluorite and calcite.
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37
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Different Flotation Performance of Ultrafine Scheelite under Two Hydrodynamic Cavitation Modes. MINERALS 2018. [DOI: 10.3390/min8070264] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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38
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Xiao W, Ke S, Quan N, Zhou L, Wang J, Zhang L, Dong Y, Qin W, Qiu G, Hu J. The Role of Nanobubbles in the Precipitation and Recovery of Organic-Phosphine-Containing Beneficiation Wastewater. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:6217-6224. [PMID: 29739191 DOI: 10.1021/acs.langmuir.8b01123] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Dissolved air flotation (DAF) is broadly applied in wastewater treatment, especially for the recovery of organic pollution with low concentration. However, the mechanism of interaction between nanoscale gas bubbles and nanoparticles in the process of DAF remains unclear. Here, we investigated the role of nanobubbles in the precipitation of styryl phosphoric acid (SPA)-Pb particles and recovering organic phosphine containined in beneficiation wastewater by UV-vis (ultraviolet-visible) spectra, microflotation tests, nanoparticle tracking analysis, dynamic light scattering, and atomic force microscopy measurements. As suggested from the results, nanobubbles can inhibit the crystallization of SPA-Pb precipitation, which makes the sediment flotation recovery below 20%. After the precipitation crystallization is completed, nanobubbles can flocculate precipitated particles, which can promote the flotation recovery of precipitated particles to 90%. On the basis of the results, we proposed a model to explain the different roles of nanobubbles in the process of precipitation and flotation of SPA-Pb particles. This study will be helpful to understand the interaction between nanobubbles and nanoparticles in the application of flotation.
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Affiliation(s)
- Wei Xiao
- School of Minerals Processing & Bioengineering , Central South University , Changsha 410083 , China
- Key Lab of Biohydrometallurgy of Ministry of Education , Changsha 410083 , China
- Key Laboratory of Interfacial Physics and Technology, Institute of Applied Physics , Chinese Academy of Sciences , Shanghai 201800 , China
| | - Shuo Ke
- Key Laboratory of Interfacial Physics and Technology, Institute of Applied Physics , Chinese Academy of Sciences , Shanghai 201800 , China
- Life and Environmental Science College , Shanghai Normal University , Shanghai 200234 , China
| | - Nannan Quan
- Key Laboratory of Interfacial Physics and Technology, Institute of Applied Physics , Chinese Academy of Sciences , Shanghai 201800 , China
- Life and Environmental Science College , Shanghai Normal University , Shanghai 200234 , China
| | - Limin Zhou
- Key Laboratory of Interfacial Physics and Technology, Institute of Applied Physics , Chinese Academy of Sciences , Shanghai 201800 , China
- University of Chinese Academy of Science , Beijing , 100049 , China
| | - Jun Wang
- School of Minerals Processing & Bioengineering , Central South University , Changsha 410083 , China
- Key Lab of Biohydrometallurgy of Ministry of Education , Changsha 410083 , China
| | - Lijuan Zhang
- Key Laboratory of Interfacial Physics and Technology, Institute of Applied Physics , Chinese Academy of Sciences , Shanghai 201800 , China
| | - Yaming Dong
- Life and Environmental Science College , Shanghai Normal University , Shanghai 200234 , China
| | - Wenqing Qin
- School of Minerals Processing & Bioengineering , Central South University , Changsha 410083 , China
- Key Lab of Biohydrometallurgy of Ministry of Education , Changsha 410083 , China
| | - Guanzhou Qiu
- School of Minerals Processing & Bioengineering , Central South University , Changsha 410083 , China
- Key Lab of Biohydrometallurgy of Ministry of Education , Changsha 410083 , China
| | - Jun Hu
- Key Laboratory of Interfacial Physics and Technology, Institute of Applied Physics , Chinese Academy of Sciences , Shanghai 201800 , China
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39
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Adsorption of a novel reagent scheme on scheelite and calcite causing an effective flotation separation. J Colloid Interface Sci 2018; 512:39-46. [DOI: 10.1016/j.jcis.2017.10.045] [Citation(s) in RCA: 155] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Revised: 10/09/2017] [Accepted: 10/11/2017] [Indexed: 12/20/2022]
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40
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Multi-Stage Flotation for the Removal of Ash from Fine Graphite Using Mechanical and Centrifugal Forces. MINERALS 2018. [DOI: 10.3390/min8010015] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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41
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Etchepare R, Azevedo A, Calgaroto S, Rubio J. Removal of ferric hydroxide by flotation with micro and nanobubbles. Sep Purif Technol 2017. [DOI: 10.1016/j.seppur.2017.05.014] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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