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Synthesis of magnetic Fe3O4-HKUST-1 nanocomposites for azo dye adsorption. ARAB J CHEM 2023. [DOI: 10.1016/j.arabjc.2023.104767] [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] Open
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2
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Hydrothermal synthesis of one-dimensional α-MoO3 nanomaterials and its unique sensing mechanism for ethanol. ARAB J CHEM 2022. [DOI: 10.1016/j.arabjc.2022.104083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Effective removal of organics from Bayer liquor through combined sonolysis and ozonation: Kinetics and mechanism. ULTRASONICS SONOCHEMISTRY 2022; 88:106106. [PMID: 35921714 PMCID: PMC9352555 DOI: 10.1016/j.ultsonch.2022.106106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Revised: 06/21/2022] [Accepted: 07/26/2022] [Indexed: 06/15/2023]
Abstract
The presence of organic compounds in the waste liquor is of serious environmental concern that has plagued the development of alumina industry (Bayer Process). The present work attempts to develop a green and efficient process for removal of organics utilizing combined effect of sonolysis and ozonation (US/O3). The effects of reaction duration, ozone concentration and ultrasonic power are assessed for sonolysis (US), ozonation (O3) and combination of sonolysis and ozonation (US/O3). The optimal conditions for US/O3 treatment system is identified to be a reaction duration of 7 h, ozone concentration of 7.65 g/h, and ultrasonic power of 600 W. The total organic carbon (TOC) removal and decolorization are 60.13% and 87.1%, respectively. The process can be scaled-up to industrial scale, which could potentially serve to be a convenient, safe and sustainable alternative to the exisiting treatment technologies. Additionally, the treated waste water can be reused contributing to an improvement in the overall economics.
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Novel Aerogel Absorbent Derived from Iron Tailings Via Atmospheric Drying. ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING 2022. [DOI: 10.1007/s13369-021-05973-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/07/2022]
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A Facile Synthesis of Highly Porous Silica Aerogel Hybrid Materials for BTX Adsorption. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2021. [DOI: 10.1246/bcsj.20200405] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Improved permeability and antifouling performance of polyethersulfone ultrafiltration membranes tailored by hydroxyapatite/boron nitride nanocomposites. CHEMOSPHERE 2021; 268:129306. [PMID: 33360002 DOI: 10.1016/j.chemosphere.2020.129306] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 12/05/2020] [Accepted: 12/11/2020] [Indexed: 06/12/2023]
Abstract
To extend the use of polyethersulfone (PES) ultrafiltration membranes in water process engineering, the membrane's wettability and anti-fouling properties should be further improved. In this context, hydroxyapatite/boron nitride (HAp/BN) nanocomposites have been prepared and intercalated into PES membranes using a non-solvent-induced phase separation process. High-quality 2D transparent boron nitride nanosheets (BN NSs) were prepared using an environmentally friendly and green-template assisted synthesis method in which 1D hexagonal hydroxyapatite nanosheets (HAp NRs) were uniformly distributed and hydrothermally immobilized at 180 °C. SEM, XRD, and Raman spectroscopy techniques were used to characterize the HAp/BN nanocomposites. PES membranes intercalated with various nanocomposite amounts (0-4 wt %) were also characterized by permeability, porosity, and contact angle measurements. Additional pathways for water molecule transport were promoted by the high surface area of the BN NSs, resulting in high permeability. Membrane wettability and antifouling properties were also improved by the inclusion of negative charge groups (OH- and PO43-) on HAp. Hybrid membranes containing 4 wt% HAp/BN showed the best overall performance with ∼97% increase in water flux, 90% rejection of bovine serum albumin (BSA), high water flux recovery ratio, low irreversible fouling, and high reversible fouling pattern. The intercalation of HAp/BN with the PES matrix therefore opens up a new direction to enhance the PES UF membranes' hydrophilicity, water flux, and antifouling capacity.
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Pilot-scale study on enhanced carbothermal reduction of low-grade pyrolusite using microwave heating. POWDER TECHNOL 2020. [DOI: 10.1016/j.powtec.2019.11.015] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Microwave pyrolysis of walnut shell for reduction process of low-grade pyrolusite. BIORESOURCE TECHNOLOGY 2019; 291:121838. [PMID: 31344635 DOI: 10.1016/j.biortech.2019.121838] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2019] [Revised: 07/13/2019] [Accepted: 07/15/2019] [Indexed: 06/10/2023]
Abstract
Replacing fossil energy by utilizing biomass as carbon source to convert metal oxides has meaning for reduction of minerals. Microwave pyrolysis of walnut shell for reduction process of low-grade pyrolusite was proposed. Thermogravimetric analysis indicated biomass pyrolysis process for reduction of pyrolusite was divided into four phases identified by temperatures: dehydration stage (<150 °C), pre-pyrolysis stage (150 °C-290 °C), curing decomposition stage (290 °C-480 °C) and carbonization stage (>480 °C), and manganese recovery reached 92.01% at 650 °C for 30 min with 18% walnut shell. The strongest preferential orientation of MnO was appeared, with good crystalline structure and no MnO2 and FeO peaks detected. The product surface became loose and porous with numerous cracks, pits and holes, and molten granules were interconnected and stacked with regular shape. The methods propose new idea of selective reduction of pyrolusite based on biomass pyrolysis by microwave heating.
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Microwave dielectric properties and thermochemical characteristics of the mixtures of walnut shell and manganese ore. BIORESOURCE TECHNOLOGY 2019; 286:121381. [PMID: 31048262 DOI: 10.1016/j.biortech.2019.121381] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 04/23/2019] [Accepted: 04/24/2019] [Indexed: 06/09/2023]
Abstract
In this work, dielectric properties and thermochemical characteristics of mixtures of walnut shell and manganese ore were systematically investigated. Results indicated that reducing manganese ore by walnut shell was divided into four stages identified by temperatures: <150 °C, 150 °C-300 °C, 300 °C-480 °C, greater than 480 °C. Higher than 200 °C, the dielectric constants (εr'), dielectric loss factors (εr″) and loss tangent coefficients (tan δ) of mixture at a ore/biomass mixing ratio of 10:1.2 were observed to suddenly drop to low levels, with 5.107 (F/M), 8.5 × 10-4 (F/M), 1.66 × 10-4 (F/M), respectively; which were attributed to the MnO2 reduced by the reductive volatiles produced by biomass pyrolysis. Meanwhile, the volatiles rendered a decrease in density and dielectric properties of the mixture. The work highlights the possibility of reducing manganese ore by walnut shell with microwave heating.
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Preparation and Characterization of Shiitake Mushroom-Based Activated Carbon with High Adsorption Capacity. ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING 2019. [DOI: 10.1007/s13369-019-03746-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Efficient cleaning extraction of silver from spent symbiosis lead-zinc mine assisted by ultrasound in sodium thiosulfate system. ULTRASONICS SONOCHEMISTRY 2018; 49:118-127. [PMID: 30082253 DOI: 10.1016/j.ultsonch.2018.07.034] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2018] [Revised: 07/14/2018] [Accepted: 07/25/2018] [Indexed: 06/08/2023]
Abstract
The process to fast recovery of silver from the spent symbiosis lead-zinc mine enhanced by ultrasound has been developed. A system composed of thiosulfate and the spent symbiosis lead-zinc mine under ultrasound radiation is researched and compared with regular methods to prove the superiority of ultrasound enhanced leaching. Oxygen is not provided by the usual way but by the cavitation of ultrasound, and the effect of ultrasonic enhanced leaching is more obvious than oxygen enhanced leaching effect. We are more authoritative by combining some valuable literature after conducting systematic experiments. The process mechanism was analyzed by fire assaying, XRD, XRF, SEM and EDS. The optimal conditions were found out through single factor experiments: stirring rate of 300 rpm, thiosulfate concentration of 75 g/L, leaching temperature of 303 K, PH of 5, leaching time of 2 h and the ultrasound power of 100 W. And the leaching rate is 77.34% under the best conditions. When the ultrasonic experiment has the same parameters as the normal, the leaching rate at five minutes under ultrasonic conditions was 73.88%, while the leaching rate was only 72.51% at two hours under normal conditions. The apparent activation energy under conventional and ultrasonic conditions is 12.47 kJ/mol and 12.35 kJ/mol, respectively, and it is proved that both are controlled by diffusion.
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Effect of microwave heating on the microstructures and kinetics of carbothermal reduction of pyrolusite ore. ADV POWDER TECHNOL 2018. [DOI: 10.1016/j.apt.2018.04.025] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Multi-scale investigation of the formation and properties of high-grade rutile TiO 2 from titanium slags using microwave heating. ROYAL SOCIETY OPEN SCIENCE 2018; 5:171858. [PMID: 30110434 PMCID: PMC6030328 DOI: 10.1098/rsos.171858] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
In this paper, the phase transition of titanium slag under microwave heating observed through electron microscopy was systematically investigated. The phase identification and transformation as well as the morphology of samples before and after each treatment were characterized using X-ray powder diffraction (XRD), Fourier-transform infrared spectroscopy, Raman spectroscopy and scanning electron microscopy (SEM). The XRD confirmed that sodium salt roasting could modify the phase composition of titanium slag. The microwave roasting in the presence of sodium salt increased the rutile TiO2 with high crystallinity after acid leaching. The Raman spectroscopy demonstrated the phase transition of titanium slag from anosovite to rutile TiO2 after a series of treatments, and the SEM analyses showed that the surface of calcined products grew plenty of rutile TiO2 with typical characteristics. The results indicate a successful process for an effective and efficient way for the utilization of both titanium slag and preparation of rutile TiO2.
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Potential of Chambersite Tailing as Raw Material for the Preparation of Glass Ceramic: Investigation on Crystallization Behavior and Crystal Structure. ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING 2018. [DOI: 10.1007/s13369-018-3061-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Correction: Preparation of magnesium silicate/carbon composite for adsorption of rhodamine B. RSC Adv 2018; 8:8625. [PMID: 35543962 PMCID: PMC9078619 DOI: 10.1039/c8ra90019a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Accepted: 02/19/2018] [Indexed: 11/25/2022] Open
Abstract
Correction for ‘Preparation of magnesium silicate/carbon composite for adsorption of rhodamine B’ by Zhiwei Sun et al., RSC Adv., 2018, 8, 7873–7882.
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Preparation of magnesium silicate/carbon composite for adsorption of rhodamine B. RSC Adv 2018; 8:7873-7882. [PMID: 35539118 PMCID: PMC9078478 DOI: 10.1039/c7ra12848g] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Revised: 02/26/2018] [Accepted: 01/31/2018] [Indexed: 11/21/2022] Open
Abstract
The surface area and pore structure, electrostatic interaction and functional groups are the main adsorption mechanisms.
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Equilibrium model analysis of waste plastics gasification using CO 2 and steam. WASTE MANAGEMENT & RESEARCH : THE JOURNAL OF THE INTERNATIONAL SOLID WASTES AND PUBLIC CLEANSING ASSOCIATION, ISWA 2017; 35:1247-1253. [PMID: 29100482 DOI: 10.1177/0734242x17736946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Utilization of carbon dioxide (CO2) in thermochemical treatment of waste plastics may significantly help to improve CO2 recycling, thus simultaneously curtailing dioxins/furans and CO2 emissions. Although CO2 is not such an effective gasifying agent as steam, a few investigations have explored the utilization of CO2 in conjunction with steam to achieve somewhat higher carbon conversion. This work presents a comparative evaluation study of CO2 and steam gasification of a typical post-consumer waste plastics mixture using an Aspen Plus equilibrium model. The effect of flow rate of gasifying medium (CO2 and/or steam) and gasification temperature on product gas composition, carbon conversion, and cold gas efficiency has been analyzed. Simulation results demonstrate that CO2 can serve as a potential gasifying agent for waste plastics gasification. The resulting product gas was rich in CO whereas CO2-steam blends yield a wider H2/CO ratio, thus extending the applications of the product gas.
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Food wastes derived adsorbents for carbon dioxide and benzene gas sorption. CHEMOSPHERE 2017; 168:326-332. [PMID: 27810531 DOI: 10.1016/j.chemosphere.2016.10.083] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Revised: 10/01/2016] [Accepted: 10/22/2016] [Indexed: 06/06/2023]
Abstract
Food wastes are produced worldwide in large quantities that could have potential to produce higher value products, including industrial adsorbents. The present work attempts valorization of food waste by CO2 activation and functionalization through nitric acid and melamine treatment. The prepared porous materials were subjected to gas phase adsorption of CO2 and benzene gases. The resultant highly porous carbon materials with surface area range from 797 to 1025 m2/g were synthesized showing uptake capacities of 4.41, 4.07, 4.18 and 4.36 mmol/g of CO2 and 345, 305, 242.5 and 380.7 mg/g of C6H6 respectively for PyF515, PyF520, PyF715 and PyF720 in the absence of doped carbon matrix. Differential thermogravimetric (DTG) analysis showed the thermostability of the precursors to validate selected initial pyrolysis temperatures (500 and 700 °C). C6H6 sorption lies mainly in the physisorption region for all adsorbents ensuring re-generation potential. PyF720 and PyF520 recorded the highest isosteric enthalpy of 64.4 kJ/mol and 48.7 kJ/mol respectively, despite the low degree of coverage of the latter. Thus, PyF515 and PyF720 demonstrated the potential for use as sustainable and cost effective adsorbents for benzene gas containment suitable for swing adsorption system.
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Synthesis of activated carbon fibers from cotton by microwave induced H3PO4 activation. J Taiwan Inst Chem Eng 2017. [DOI: 10.1016/j.jtice.2016.10.036] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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A comparison of ultrasound-augmented and conventional leaching of silver from sintering dust using acidic thiourea. ULTRASONICS SONOCHEMISTRY 2017; 34:222-231. [PMID: 27773239 DOI: 10.1016/j.ultsonch.2016.05.038] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Revised: 05/10/2016] [Accepted: 05/24/2016] [Indexed: 06/06/2023]
Abstract
In the process of steel manufacture, up to ten millions of tons of sintering dust (SD) are produced annually in China, which contain noble metals such as Ag. Therefore, recovery of silver (Ag) from SD could be a potential economic and environmental activity. The purpose of this article is to generate information about reaction kinetics of silver leaching with thiourea from SD, comparing the conventional and ultrasonic-augment leaching. The effects of various control parameters such as the ultrasound power, particle size, leaching temperature and thiourea concentration on leaching rate of silver were studied. The results showed 89% silver recovery for conventional process against 95% for ultrasound assisted leaching. The ultrasonic wave increased the leaching rate and shorten the reaction time. The rate controlling step was analyzed using shrinking core model and the rate controlling step is identified to be the diffusion through the product layer in both conventional and ultrasonic-augment leaching processes. The activation energies were estimated to be 28.01kJ/mol and 18.19kJ/mol, and the reaction order were 0.89 and 0.71, respectively.
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Separation of indium from iron in a rotating packed bed contactor using Di-2-ethylhexylphosphoric acid. Sep Purif Technol 2016. [DOI: 10.1016/j.seppur.2016.03.017] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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A Facile Synthesis of Mesoporous Sulfonated Carbon and Its Structural Properties. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2016; 16:1202-1206. [PMID: 27398587 DOI: 10.1166/jnn.2016.10644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Mesoporous sulfonated carbons (SC) have been synthesized using tetraethyl orthosilicate (TEOS) as a silica source and sucrose as carbon source. The synthesized SC samples were carbonized in N₂flow at various high temperatures and then passing high purity air at room temperature. In this study, we extended the idea to deposit more oxygen functional groups into the surface of SC being high micropores for the favorable adsorption applications. The resulting materials were characterized by using XRD, BET surface area, TPD, TEM, TGA and FTIR techniques. Mesoporous SC materials with controllable pore diameters are expected to be significant to future research concerning the improvement of catalysis, supercapacitors, fuel cells and adsorption.
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Preparation of U3O8 by calcination from ammonium uranyl carbonate in microwave fields: Process optimization. ANN NUCL ENERGY 2015. [DOI: 10.1016/j.anucene.2015.07.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Process Optimization of the Preparation of Vanadium Nitride from Vanadium Pentoxide. ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING 2015. [DOI: 10.1007/s13369-015-1763-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Synthesis of porous sulfonated carbon as a potential adsorbent for phenol wastewater. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2015; 72:1594-1600. [PMID: 26524451 DOI: 10.2166/wst.2015.372] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The work reports a facile synthesis procedure for preparation of porous sulfonated carbons and its suitability for adsorption of phenol. The sulfonated carbon was synthesized utilizing a simplified, single-step, shorter duration process by sulfonation, dehydration and carbonization of sucrose in sulfuric acid and tetraethylorthosilicate. The surface and internal structures of the adsorbents were characterized utilizing various characterization techniques to understand the porous nature and surface functional groups of the porous matrix. Adsorption capacity was found to be highest for the sample heat treated at 600 °C, with the maximum adsorption capacity of 440 mg/g at 30 °C. The adsorption isotherms were tested with the Freundlich and Langmuir adsorption isotherms models to identify the appropriate adsorption mechanism.
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Regeneration of spent catalyst from vinyl acetate synthesis as porous carbon: Process optimization using RSM. Chem Eng Res Des 2014. [DOI: 10.1016/j.cherd.2013.11.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Process optimization of thermal regeneration of spent coal based activated carbon using steam and application to methylene blue dye adsorption. J Taiwan Inst Chem Eng 2014. [DOI: 10.1016/j.jtice.2013.10.019] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Elemental mercury adsorption on sulfur-impregnated porous carbon - a review. ENVIRONMENTAL TECHNOLOGY 2014; 35:18-26. [PMID: 24600836 DOI: 10.1080/21622515.2013.804589] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The presence of elemental mercury in wellhead natural gas is an important industrial problem, since even low levels of mercury can damage cryogenic aluminium heat exchangers and other plant equipment. Mercury present in the natural gas stream will also dramatically shorten the useful life of precious metal catalysts. The present work reviews the overall process of elemental mercury removal in practice using non-regenerative adsorbents (e.g. sulfur-impregnated porous carbon), addressing the various influencing parameters such as the method of sulfur impregnation, the impregnation temperature, the sulfur to carbon ratio, the impregnation time, the impact of flue gas constituents, the effect of processing temperature, and the nature of any carbon-containing functional groups present. The distribution of elemental sulfur is found to be the key to developing an effective adsorbent, rather than quantity of sulfur impregnated. Modifying or developing an adsorbent for elemental mercury removal from natural gas needs a detail physical and chemical characteristics assessment of the adsorbent.
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KOH-based porous carbon from date palm seed: preparation, characterization, and application to phenol adsorption. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2014; 70:1633-1640. [PMID: 25429451 DOI: 10.2166/wst.2014.419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The date palm seed being one of the major forms of biomass produced from the date industry in UAE, its potential to be an appropriate precursor for the preparation of porous carbon utilizing KOH as an activating agent is assessed in the present work. The porous carbon is prepared at an activation temperature of 600 °C, impregnation ratio of 2, and activation duration of 1 hour, in an inert atmosphere using a conventional horizontal furnace. The resultant porous carbon has a Brunauer-Emmett-Teller surface area of 892 m(2)/g, pore volume of 0.45 cm(3)/g, and an average pore diameter of 1.97 nm. This porous carbon was used for adsorption studies at different initial concentrations (100-400 mg/l) and temperatures (30-50 °C). The adsorption isotherm parameters for the Langmuir and Freundlich models were determined using experimental adsorption data and it was found that both Langmuir and Freundlich isotherms described well the adsorption behavior of phenol on porous carbon. The mono layer adsorption capacity was observed to be 333 mg/g, which is highest for the reported date pam seed biomass-based porous carbon. From the data obtained, it was concluded that the removal of phenol from aqueous solution by porous carbon prepared from data palm seed is a low-cost process with an extremely high performance.
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Process optimization of preparation of ZnO-porous carbon composite from spent catalysts using one step activation. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2012; 12:6231-6239. [PMID: 22962730 DOI: 10.1166/jnn.2012.6426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The process parameters of one step preparation of ZnO/Activated Carbon (AC) composite materials, from vinyl acetate synthesis spent catalyst were optimized using response surface methodology (RSM) and the central composite rotatable design (CCD). Regeneration temperature, time and flow rate of CO2 were the process variables, while the iodine number and the yield were the response variables. All the three process variables were found to significantly influence the yield of the regenerated carbon, while only the regeneration temperature and CO2 flow rate were found to significantly affect the iodine number. The optimized process conditions that maximize the yield and iodine adsorption capacity were identified to be a regeneration temperature of 950 degrees C, time of 120 min and flow rate of CO2 of 600 ml/min, with the corresponding yield and iodine number to be in excess of 50% and 1100 mg/g. The BET surface area of the regenerated composite was estimated to be 1263 m2/g, with micropore to mesopore ratio of 0.75. The pore volume was found to have increased 6 times as compared to the spent catalyst. The composite material (AC/ZnO) with high surface area and pore volume coupled with high yield augur economic feasibility of the process. EDS and XRD spectrum indicate presence of ZnO in the regenerated samples.
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Process optimization of vapor phase pyridine synthesis using response surface methodology. KINETICS AND CATALYSIS 2012. [DOI: 10.1134/s0023158412020139] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Optimization of hydrous ferrous sulfate dehydration by microwave heating using response surface methodology. THE JOURNAL OF MICROWAVE POWER AND ELECTROMAGNETIC ENERGY : A PUBLICATION OF THE INTERNATIONAL MICROWAVE POWER INSTITUTE 2012; 46:206-214. [PMID: 24432588 DOI: 10.1080/08327823.2012.11689837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The work relates to assessing the ability of the microwave for dehydration of large amount of waste hydrous ferrous sulfate generated from the titanium pigment process industry. The popular process optimization tool of response surface methodology with central composite design was adopted to estimate the effect of dehydration. The process variables were chosen to be power input, duration of heating and the bed thickness, while the response variable being the weight loss. An increase in all the three process variables were found to significantly increase the weight loss, while the effect of interaction among the parameters were found to be insignificant. The optimized process conditions that contribute to the maximum weight loss were identified to be a power input of 960 W, duration of heating of 14 min and bed thickness of 5 cm, resulting in a weight loss of 31.44%. The validity of the optimization process was tested with the repeat runs at optimized conditions.
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Coupling and absorbing behavior of microwave irradiation on the Co(C2O4)·2H2O:Co3O4 system. J Taiwan Inst Chem Eng 2011. [DOI: 10.1016/j.jtice.2010.03.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Preparation of high surface area activated carbon from coconut shells using microwave heating. BIORESOURCE TECHNOLOGY 2010; 101:6163-6169. [PMID: 20303745 DOI: 10.1016/j.biortech.2010.03.001] [Citation(s) in RCA: 142] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2009] [Revised: 02/04/2010] [Accepted: 03/01/2010] [Indexed: 05/27/2023]
Abstract
The present study attempts to utilize coconut shell to prepare activated carbon using agents such as steam, CO(2) and a mixture of steam-CO(2) with microwave heating. Experimental results show that the BET surface area of activated carbons irrespective of the activation agent resulted in surface area in excess of 2000 m(2)/g. The activation time using microwave heating is very much shorter, while the yield of the activated carbon compares well with the conventional heating methods. The activated carbon prepared using CO(2) activation has the largest BET surface area, however the activation time is approximately 2.5 times higher than the activation using steam or mixture of steam-CO(2). The chemical structure of activated carbons examined using Fourier transformed infra-red spectra (FTIR) did not show any variation in the surface functional groups of the activated carbon prepared using different activation agents.
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Textural characteristics of activated carbon by single step CO2 activation from coconut shells. J Taiwan Inst Chem Eng 2010. [DOI: 10.1016/j.jtice.2009.09.004] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Leaching zinc from spent catalyst: process optimization using response surface methodology. JOURNAL OF HAZARDOUS MATERIALS 2010; 176:1113-1117. [PMID: 20060224 DOI: 10.1016/j.jhazmat.2009.11.125] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2009] [Revised: 11/22/2009] [Accepted: 11/24/2009] [Indexed: 05/28/2023]
Abstract
The spent catalyst from vinyl acetate synthesis contains large quantity of zinc. The present study attempts to leach zinc using a mixture of ammonia, ammonium carbonate and water solution, after microwave treatment. The effect of important parameters such as leaching time, liquid/solid ratio and the ammonia concentration was investigated and the process conditions were optimized using surface response methodology (RSM) based on central composite design (CCD). The optimum condition for leaching of zinc from spent catalyst was identified to be a leaching time of 2.50 h, a liquid/solid ratio of 6 and ammonia concentration 5.37 mol/L. A maximum of 97% of zinc was recovered under the optimum experimental conditions. The proposed model equation using RSM has shown good agreement with the experimental data, with a correlation coefficient (R(2)) of 0.95. The samples were characterized before and after leaching using X-ray diffraction (XRD), nitrogen adsorption and scanning electron microscope (SEM).
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Removal of arsenic from aqueous solution using electrocoagulation. JOURNAL OF HAZARDOUS MATERIALS 2009; 167:966-969. [PMID: 19231076 DOI: 10.1016/j.jhazmat.2009.01.081] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2008] [Revised: 01/21/2009] [Accepted: 01/21/2009] [Indexed: 05/26/2023]
Abstract
Removal of arsenic from aqueous solution was carried out using electrocoagulation. Experiments were conducted using mild steel sacrificial anode covering wide range in operating conditions to assess the removal efficiency. The maximum arsenic removal efficiency was recorded as 94% under optimum condition. The electrocoagulation mechanism of arsenic removal has been developed to understand the effect of applied charge and electrolyte pH on arsenic removal efficiency. Further the experimental data were tested with different adsorption isotherm model to describe the electrocoagulation process.
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Ozonation of tannery effluent for removal of cod and color. JOURNAL OF HAZARDOUS MATERIALS 2009; 166:150-4. [PMID: 19118944 DOI: 10.1016/j.jhazmat.2008.11.035] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2008] [Revised: 09/23/2008] [Accepted: 11/05/2008] [Indexed: 05/22/2023]
Abstract
Ozonation of leather dye effluent for removal of color and COD reduction covering wide range in operating parameters forms the scope of the present work. The influence of parameters such as influent pH, ozone flow rate and initial effluent concentration on ozonation efficiency has been critically examined. It has been observed from the present investigation that a maximum of COD removal efficiency of 92% has been achieved under optimum operating conditions. Further the biodegradability index of the tannery effluent has increased from an initial value of 0.18 to 0.49 during ozonation indicating favorable adaptation of ozonation as a primer to the biochemical technique to enhance the efficiency of biochemical treatment.
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Kinetics of Cholesterol Extraction Using Supercritical Carbon Dioxide with Cosolvents. Ind Eng Chem Res 2008. [DOI: 10.1021/ie070703q] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Analysis of Various Experimental Methods and Preparation of Mesoporous Activated Carbon Powders from Sawdust Using Phosphoric Acid. PARTICULATE SCIENCE AND TECHNOLOGY 2007. [DOI: 10.1080/02726350701490896] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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