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Song J, Li Y, Chen L, Zhao D, Yu S, Huang L. Preparation of KHA/SA/MMT composites and their adsorption properties for Rhodamine B. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:24220-24234. [PMID: 38436849 DOI: 10.1007/s11356-024-32652-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Accepted: 02/22/2024] [Indexed: 03/05/2024]
Abstract
Two natural adsorbent materials, potassium humate (KHA) and montmorillonite (MMT), were successfully prepared by embedding them in sodium alginate (SA) gel spheres through physical cross-linking with CaCl2. And CaCO3 was used as a porogenic agent to prepare the porous composites, KHA/SA/MMT. The materials were characterized by using XRD, TGA, SEM, and N2 adsorption/desorption equipment. The results showed that MMT and KHA were successfully embedded in the SA gel; the introduction of MMT increased the thermal stability of the composites and the embedding of MMT, and the porogenic effect of CaCO3 increased the specific surface area of the composites substantially, which provided favorable conditions for adsorption and treatment of pollutants. In addition, a one-way exploratory experiment yielded a higher removal rate of Rhodamine B (RhB) at D = 0.6 g/L, pH = 5, C0 = 100 mg/L, and t = 360 min. The adsorption kinetics and adsorption isotherm conformed to the secondary kinetic model and Langmuir model, respectively, and the maximum adsorption of RhB by KHA/SA/MMT could reach up to 884.96 mg/g at 303 K. The adsorption mechanism for RhB was shown by FT-IR and XPS analyses to be possibly bound by non-covalent bonding forces. After seven consecutive adsorption-desorption cycles, the adsorption of RhB by KHA/SA/MMT still reached 80.75%. Therefore, the prepared gel spheres have the advantages of easy regeneration and efficient reuse and great potential for application in purifying RhB from wastewater.
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Affiliation(s)
- Jie Song
- Shaanxi University of Science & Technology, Xi'an, 710021, China.
| | - Yidan Li
- Shaanxi University of Science & Technology, Xi'an, 710021, China
| | - Lijun Chen
- Shaanxi University of Science & Technology, Xi'an, 710021, China
| | - Dong Zhao
- Shaanxi University of Science & Technology, Xi'an, 710021, China
| | - Shuang Yu
- Shaanxi University of Science & Technology, Xi'an, 710021, China
| | - Liangxian Huang
- Shaanxi University of Science & Technology, Xi'an, 710021, China
- Shaanxi Research Institute of Agricultural Products Processing Technology, Xi'an, 710021, China
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Miao P, Gao J, Han X, Zhao Y, Chen T. Adsorption of Levofloxacin onto Graphene Oxide/Chitosan Composite Aerogel Microspheres. Gels 2024; 10:81. [PMID: 38275855 PMCID: PMC10815225 DOI: 10.3390/gels10010081] [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: 12/27/2023] [Revised: 01/18/2024] [Accepted: 01/20/2024] [Indexed: 01/27/2024] Open
Abstract
The removal of pharmaceutical residues from water resources using bio-based materials is very important for human safety and health. Bio-based graphene oxide/chitosan (GO/CS) aerogel microspheres were fabricated with emulsification and cross-linking, followed by freeze drying, and were used for the adsorption of levofloxacin (LOF). The obtained GO/CS aerogel microspheres were characterized with scanning electron microscopy (SEM), Fourier-transform infrared (FTIR), and thermogravimetry (TG). The effects of GO content, pH value, and temperature on their adsorption capacity were investigated. With the incorporation of 40 wt% GO, the adsorption capacity increased from 9.9 to 45.6 mg/g, and the highest adsorption capacity, 51.5 mg/g, was obtained at pH = 8 and T = 25 °C. In addition, to obtain deeper insight into the adsorption process, the thermodynamics and kinetics of the process were also investigated with four different models of LOF adsorption. The thermodynamic modeling results revealed that LOF adsorption is exothermic, and the kinetic investigation demonstrated that LOF adsorption is generally consistent with a pseudo-first-order rate law.
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Affiliation(s)
- Pengpai Miao
- School of Pharmacy, Hubei University of Science and Technology, Xianning 437100, China;
- School of Nuclear Technology and Chemistry & Biology, Hubei Key Laboratory of Radiation Chemistry and Functional Materials, Hubei University of Science and Technology, Xianning 437100, China; (X.H.); (Y.Z.)
| | - Jie Gao
- School of Nuclear Technology and Chemistry & Biology, Hubei Key Laboratory of Radiation Chemistry and Functional Materials, Hubei University of Science and Technology, Xianning 437100, China; (X.H.); (Y.Z.)
| | - Xiaobing Han
- School of Nuclear Technology and Chemistry & Biology, Hubei Key Laboratory of Radiation Chemistry and Functional Materials, Hubei University of Science and Technology, Xianning 437100, China; (X.H.); (Y.Z.)
| | - Yuan Zhao
- School of Nuclear Technology and Chemistry & Biology, Hubei Key Laboratory of Radiation Chemistry and Functional Materials, Hubei University of Science and Technology, Xianning 437100, China; (X.H.); (Y.Z.)
| | - Tao Chen
- School of Nuclear Technology and Chemistry & Biology, Hubei Key Laboratory of Radiation Chemistry and Functional Materials, Hubei University of Science and Technology, Xianning 437100, China; (X.H.); (Y.Z.)
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Guo H, Qin Q, Chang JS, Lee DJ. Modified alginate materials for wastewater treatment: Application prospects. BIORESOURCE TECHNOLOGY 2023; 387:129639. [PMID: 37549712 DOI: 10.1016/j.biortech.2023.129639] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2023] [Revised: 08/03/2023] [Accepted: 08/04/2023] [Indexed: 08/09/2023]
Abstract
Sodium alginate is a natural macromolecule widely used because of its abundance, low cost of acquisition, and rich hydroxyl and carboxyl groups in the matrix. The physical modification of sodium alginate can be made by blending it with polymer materials. The so-yielded alginate complex is commonly unstable in an aqueous environment due to alginate backbones' high hydrophilicity. The chemical modification can remove its hydrophilic groups and introduce special functional groups or polymers onto the alginate backbones to provide excess reaction sites for specific reactions and effective complexation sites for accommodating antibiotics, dyes, heavy metal ions, and radioactive elements. Sodium alginate has been used in water treatment engineering under revised modification protocols. This article also reviews the latest modification protocols for sodium alginate and outlines the novel application of the modified materials. The limitations of modified sodium alginate materials are described, and research prospects are put forward.
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Affiliation(s)
- Hongliang Guo
- College of Forestry, Northeast Forestry University, Harbin 150040, China
| | - Qing Qin
- College of Forestry, Northeast Forestry University, Harbin 150040, China
| | - Jo-Shu Chang
- Research Center for Smart Sustainable Circular Economy, Tunghai University, Taichung 407, Taiwan; Department of Chemical Engineering, National Cheng Kung University, Tainan, Taiwan; Department of Chemical and Materials Engineering, Tunghai University, Taichung 407, Taiwan
| | - Duu-Jong Lee
- Department of Mechanical Engineering, City University of Hong Kong, Kowloon Tong, Hong Kong; Department of Chemical Engineering & Materials Sci., Yuan Ze University, Chung-li 32003, Taiwan.
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Miao P, Sang Y, Gao J, Han X, Zhao Y, Chen T. Adsorption and Recognition Property of Tyrosine Molecularly Imprinted Polymer Prepared via Electron Beam Irradiation. Polymers (Basel) 2023; 15:4048. [PMID: 37896292 PMCID: PMC10610430 DOI: 10.3390/polym15204048] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 09/30/2023] [Accepted: 10/09/2023] [Indexed: 10/29/2023] Open
Abstract
To realize the selective separation of L-tyrosine (L-Tyr) and avoid the drawbacks of traditional thermal polymerization, electron beam irradiation polymerization was developed for the fabrication of L-Tyr molecularly imprinted polymers (MIPs). Firstly, L-Tyr MIPs were prepared with methacrylic acid and ethylene glycol dimethacrylate and without an initiator. Then, the influence of absorbed dosage and temperature on the adsorption capacity of L-Tyr, as well as the thermodynamic behavior, were investigated. The maximum adsorption capacity of 10.96 mg/g for MIPs was obtained with an irradiation dosage of 340 kGy under 15 °C, and the ΔH0 and ΔS0 of the adsorption process are -99.79 kJ/mol and -0.31 kJ/mol·K, respectively. In addition, the effect of adsorption time on adsorption performance was evaluated under different initial concentrations, and the kinetic behavior was fitted with four different models. Finally, the recognition property of the obtained MIPs was investigated with L-Tyr and two analogues. The obtained MIPs have an imprinting factor of 5.1 and relatively high selective coefficients of 3.9 and 3.5 against L-tryptophan and L-phenylalanine, respectively. This work not only provided an L-Tyr MIP with high adsorption capacity and selectivity but also provided an effective and clean method for the synthesis of MIPs.
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Affiliation(s)
| | | | - Jie Gao
- Hubei Key Laboratory of Radiation Chemistry and Functional Materials, School of Pharmacy, School of Nuclear Technology and Chemistry & Biology, Hubei University of Science and Technology, Xianning 437100, China; (P.M.); (Y.S.); (X.H.); (Y.Z.)
| | | | | | - Tao Chen
- Hubei Key Laboratory of Radiation Chemistry and Functional Materials, School of Pharmacy, School of Nuclear Technology and Chemistry & Biology, Hubei University of Science and Technology, Xianning 437100, China; (P.M.); (Y.S.); (X.H.); (Y.Z.)
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Allahkarami E, Allahkarami E, Azadmehr A. Enhancing the efficiency of Ni(II), Cd(II), and Cu(II) adsorption from aqueous solution using schist/alginate composite: batch and continuous studies. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:105504-105521. [PMID: 37715033 DOI: 10.1007/s11356-023-29808-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 09/06/2023] [Indexed: 09/17/2023]
Abstract
The main aim of this research is focused on the synthesis of schist/alginate composite (SC/AL) adsorbent and its utilization for the removal of Ni(II), Cu(II), and Cd(II) from waste streams using batch and column processes. The characterization of developed adsorbent was performed by X-ray fluorescence, X-ray diffraction, FTIR, and BET analyses. The most influential operating parameters (pH, contact time, temperature and initial adsorbate concentration) on the adsorption capacity of pollutants were examined to evaluate the performance of developed adsorbent. The kinetic and equilibrium adsorption results at pH 5.0 indicated that SC/AL composite had good adsorption capacity (qmax) for Ni(II), Cu(II), and Cd(II) estimated at 124.79 mg/g, 111.78 mg/g, and 119.78 mg/g, respectively. From the kinetic viewpoint, the good fit of pseudo-first-order kinetic model to the kinetic adsorption data indicated that dominant interaction of heavy metals with SC/AL composite was physisorption. The results of thermodynamic studies indicated that the adsorption of heavy metals onto SC/AL composite was endothermic and spontaneous in nature. The adsorption capacity of developed adsorbent could still reach relatively 85% of the original one after completing fifth cycle. Therefore, the reusability results of SC/AL composite were quite satisfied, making the developed adsorbent a commercially attractive and green method. Finally, in column studies, the effect of initial concentration of pollutants at pH 5.0 on the removal of heavy metal ions was investigated. The Thomas and Yoon-Nelson models provided a satisfactory explanation for the results of column data.
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Affiliation(s)
- Esmaeil Allahkarami
- Department of Petroleum Engineering, Faculty of Petroleum, Gas and Petrochemical Engineering, Persian Gulf University, Bushehr, Iran
| | - Ebrahim Allahkarami
- Department of Mining Engineering, Amirkabir University of Technology, Tehran, Iran
| | - Amirreza Azadmehr
- Department of Mining Engineering, Amirkabir University of Technology, Tehran, Iran.
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Lotfy D, El-Sayyad GS, Shehata N. Hexamethylenetetramine functionalized graphene oxide-alginate beads nanocomposite as efficient sorbent for dye from aqueous solution. Int J Biol Macromol 2023; 228:754-772. [PMID: 36563810 DOI: 10.1016/j.ijbiomac.2022.12.208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2022] [Revised: 12/15/2022] [Accepted: 12/18/2022] [Indexed: 12/25/2022]
Abstract
In this study, a novel eco-friendly sorbent, hexamethylenetetramine (HMTA) functionalized calcium alginate (AG) immobilized graphene oxide (GO) composite (AG-GO-HMTA) and hexamethylenetetramine functionalized calcium alginate composite (AG-HMTA) were prepared. Adsorption factors including pH impact, contact time, initial dye concentration, dosage, selectivity and reusability on methylene blue (MB) removal from water were investigated. The prepared sorbents were characterized using structural (e.g. XRD, FT-IR, EDAX), thermal (e.g. TGA, DTG), and morphological (e.g. SEM, BET) analysis techniques. The equilibrium adsorption data was described by the Langmuir and Freundlich isotherms, and the adsorption kinetic and thermodynamic parameters were investigated. The field studies and regeneration of the beads were investigated. AG-GO HMTA displays a well-defined porous structure and this desired morphology arising from high quality dispersion of HMTA within the AG-GO matrix. The highest adsorption capacities were observed at pH ∼ 5, meanwhile the adsorption of MB dye molecules, positively charged, onto the beads became faster due to strong electrostatic interactions. When the value of dosage is 0.01 g, the equilibrium concentration (mg/g) are maximum at 103, 110, 164, 168 mg/g for AG, AG-GO, AG-HMTA and AG-GO-HMTA, respectively. The present work shows that pseudo first order could describe the MB adsorption onto AG while it couldn't describe the MB adsorption onto the functionalized sorbents due to the hybrid materials complicity.
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Affiliation(s)
- Dina Lotfy
- Environmental Science and Industrial Development Department, Faculty of Postgraduate Studies for Advanced Sciences (PSAS), Beni-Suef University, Beni-Suef 62511, Egypt; Beni-Suef Potable Water and Sanitation Company, A Subsidiary of the Holding Company for Water and Sanitation, Beni-Suef, Egypt
| | - Gharieb S El-Sayyad
- Microbiology and Immunology Department, Faculty of Pharmacy, Galala University, New Galala City, Suez, Egypt; Drug Microbiology Lab, Drug Radiation Research Department, National Center for Radiation Research and Technology (NCRRT), Egyptian Atomic Energy Authority (EAEA), Cairo, Egypt.
| | - Nabila Shehata
- Environmental Science and Industrial Development Department, Faculty of Postgraduate Studies for Advanced Sciences (PSAS), Beni-Suef University, Beni-Suef 62511, Egypt
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Nayl AA, Abd-Elhamid AI, Arafa WAA, Ahmed IM, AbdEl-Rahman AME, Soliman HMA, Abdelgawad MA, Ali HM, Aly AA, Bräse S. A Novel P@SiO 2 Nano-Composite as Effective Adsorbent to Remove Methylene Blue Dye from Aqueous Media. MATERIALS (BASEL, SWITZERLAND) 2023; 16:514. [PMID: 36676250 PMCID: PMC9864475 DOI: 10.3390/ma16020514] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 12/23/2022] [Accepted: 12/28/2022] [Indexed: 06/17/2023]
Abstract
This work aims to prepare a novel phosphate-embedded silica nanoparticles (P@SiO2) nanocomposite as an effective adsorbent through a hydrothermal route. Firstly, a mixed solution of sodium silicate and sodium phosphate was passed through a strong acidic resin to convert it into hydrogen form. After that, the resultant solution was hydrothermally treated to yield P@SiO2 nanocomposite. Using kinetic studies, methylene blue (MB) dye was selected to study the removal behavior of the P@SiO2 nanocomposite. The obtained composite was characterized using several advanced techniques. The experimental results showed rapid kinetic adsorption where the equilibrium was reached within 100 s, and the pseudo-second-order fitted well with experimental data. Moreover, according to Langmuir, one gram of P@SiO2 nanocomposite can remove 76.92 mg of the methylene blue dye. The thermodynamic studies showed that the adsorption process was spontaneous, exothermic, and ordered at the solid/solution interface. Finally, the results indicated that the presence of NaCl did not impact the adsorption behavior of MB dye. Due to the significant efficiency and promising properties of the prepared P@SiO2 nanocomposite, it could be used as an effective adsorbent material to remove various cationic forms of pollutants from aqueous solutions in future works.
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Affiliation(s)
- AbdElAziz A. Nayl
- Department of Chemistry, College of Science, Jouf University, Sakaka 72341, Aljouf, Saudi Arabia
| | - Ahmed I. Abd-Elhamid
- Composites and Nanostructured Materials Research Department, Advanced Technology and New Materials Research Institute, City of Scientific Research and Technological Applications (SRTA-City), New Borg Al-Arab 21934, Egypt
| | - Wael A. A. Arafa
- Department of Chemistry, College of Science, Jouf University, Sakaka 72341, Aljouf, Saudi Arabia
| | - Ismail M. Ahmed
- Department of Chemistry, College of Science, Jouf University, Sakaka 72341, Aljouf, Saudi Arabia
| | - Aref M. E. AbdEl-Rahman
- Composites and Nanostructured Materials Research Department, Advanced Technology and New Materials Research Institute, City of Scientific Research and Technological Applications (SRTA-City), New Borg Al-Arab 21934, Egypt
| | - Hesham M. A. Soliman
- Composites and Nanostructured Materials Research Department, Advanced Technology and New Materials Research Institute, City of Scientific Research and Technological Applications (SRTA-City), New Borg Al-Arab 21934, Egypt
| | - Mohamed A. Abdelgawad
- Department of Pharmaceutical Chemistry, College of Pharmacy, Jouf University, Sakaka 72341, Aljouf, Saudi Arabia
| | - Hazim M. Ali
- Department of Chemistry, College of Science, Jouf University, Sakaka 72341, Aljouf, Saudi Arabia
| | - Ashraf A. Aly
- Chemistry Department, Faculty of Science, Organic Division, Minia University, El-Minia 61519, Egypt
| | - Stefan Bräse
- Institute of Organic Chemistry (IOC), Karlsruhe Institute of Technology (KIT), Fritz-Haber-Weg 6, 76133 Karlsruhe, Germany
- Institute of Biological and Chemical Systems-Functional Molecular Systems (IBCS-FMS), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
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Bamboo Nanocellulose/Montmorillonite Nanosheets/Polyethyleneimine Gel Adsorbent for Methylene Blue and Cu(II) Removal from Aqueous Solutions. Gels 2023; 9:gels9010040. [PMID: 36661806 PMCID: PMC9858328 DOI: 10.3390/gels9010040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 11/30/2022] [Accepted: 12/01/2022] [Indexed: 01/06/2023] Open
Abstract
In recent years, the scarcity of pure water resources has received a lot of attention from society because of the increasing amount of pollution from industrial waste. It is very important to use low-cost adsorbents with high-adsorption performance to reduce water pollution. In this work, a gel adsorbent with a high-adsorption performance on methylene blue (MB) and Cu(II) was prepared from bamboo nanocellulose (BCNF) (derived from waste bamboo paper) and montmorillonite nanosheet (MMTNS) cross-linked by polyethyleneimine (PEI). The resulting gel adsorbent was characterized by Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (SEM), X-ray photoelectron spectroscopic (XPS), etc. The results indicated that the MB and Cu(II) adsorption capacities of the resulting gel adsorbent increased with the solution pH, contact time, initial concentration, and temperature before equilibrium. The adsorption processes of MB and Cu(II) fitted well with the fractal-like pseudo-second-order model. The maximal adsorption capacities on MB and Cu(II) calculated by the Sips model were 361.9 and 254.6 mg/g, respectively. The removal of MB and Cu(II) from aqueous solutions mainly included electrostatic attraction, ion exchange, hydrogen bonding interaction, etc. These results suggest that the resulting gel adsorbent is an ideal material for the removal of MB and Cu(II) from aqueous solutions.
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Wasilewska M, Deryło-Marczewska A. Adsorption of Non-Steroidal Anti-Inflammatory Drugs on Alginate-Carbon Composites-Equilibrium and Kinetics. MATERIALS (BASEL, SWITZERLAND) 2022; 15:ma15176049. [PMID: 36079436 PMCID: PMC9457085 DOI: 10.3390/ma15176049] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 08/20/2022] [Accepted: 08/26/2022] [Indexed: 05/14/2023]
Abstract
In this work, alginate-carbon composites with different active carbon content were synthesized and studied by various techniques. The obtained materials can be used as adsorbents in the processes of removing organic pollutants from water. In this study, the effect of the immobilization of activated carbon in calcium alginate was investigated. Textural properties were determined by measuring low-temperature nitrogen adsorption/desorption isotherms. The largest specific surface area was recorded for ALG_C8 and amounted to 995 m2/g. The morphology of alginate materials was determined on the basis of scanning electron microscopy. The adsorption properties were estimated based on the measurements of equilibrium and adsorption kinetics. The highest sorption capacities were 0.381 and 0.873 mmol/g for ibuprofen and diclofenac, respectively. The generalized Langmuir isotherm was used to analyze the equilibrium data. A number of equations and kinetic models were used to describe the adsorption rate data, including first (FOE) and second (SOE) order kinetic equations, 1,2-mixed-order kinetic equation (MOE), fractal-like MOE equation (f-MOE), multi-exponential equation (m-exp), in addition to diffusion models: intraparticle diffusion model (IDM) and pore diffusion model (PDM). Thermal stability was determined on the basis of data from thermal analysis in an atmosphere of synthetic air.
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Macroalgal-Derived Alginate Soil Amendments for Water Retention, Nutrient Release Rate Reduction, and Soil pH Control. Gels 2022; 8:gels8090548. [PMID: 36135260 PMCID: PMC9498892 DOI: 10.3390/gels8090548] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 08/20/2022] [Accepted: 08/22/2022] [Indexed: 11/16/2022] Open
Abstract
There is a need to develop sustainably sourced products that can address the needs for improved water retention in soils, slow the release rate of fertilizers (to prevent leaching and downstream eutrophication), and control soil pH for use in agriculture. This article investigates the use of industrial kelp solid waste extracted alginate (IW) slurries to produce soil amendment beads, potentially improving soil water retention, acting as slow-release fertilizers (SRFs), and combined with limestone controls soil pH levels. Alginate extracted from the IW was determined to have a lower guluronic (G) to mannuronic (M) acid ratio than pure laboratory-grade (LG) alginate (0.36 vs. 0.53). Hydrogels produced from the IW alginate achieved significantly higher equilibrium swelling ratios (1 wt% IW = 1.80) than LG hydrogels with similar concentrations (1 wt% LG = 0.61). Hydrogel beads were impregnated with ammonium nitrate and potassium chloride to produce potential SRFs. The release rates of K+ and NO3− nutrients from the produced SRFs into deionised water were decreased by one order of magnitude compared to pure salts. The nutrient release rates of the IW-based SRFs were shown to be similar to SRFs produced from LG alginate. Hydrogel beads were impregnated with limestone, and it was determined that the alginate-based hydrogels could significantly decrease the nutrient release rate. Using industrial kelp solid waste extracted alginate slurries shows potential for soil amendments production. This report emphasises, for the first time, the use of a crude alginate product in soil amendment formation. Further, it demonstrates slower release rates and soil pH control.
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