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Bansal P, Purwar R. Polyacrylonitrile/clay nanofibrous nanocomposites for efficient adsorption of Cr (VI) ions. JOURNAL OF POLYMER RESEARCH 2021. [DOI: 10.1007/s10965-020-02362-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Akinterinwa A, Oladele E, Adebayo A, Gurgur E, Iyanu OO, Ajayi O. Cross-linked-substituted (esterified/etherified) starch derivatives as aqueous heavy metal ion adsorbent: a review. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2020; 82:1-26. [PMID: 32910789 DOI: 10.2166/wst.2020.332] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Starch is a biopolymer with outstanding economic and environmentally friendly attributes which has driven technological innovations to enhance its applications in food and non-food industries. Starch is constituted by O-H groups with valency and electronic characteristics that can initiate adsorption of aqueous heavy metal ions (AHMIs). However, this can be enhanced using various modification sequences. A common procedure is the cross-linking and substitution of the O-H groups via esterification and/or etherification reactions to produce starch derivative adsorbents (SDAs) with improved structural and functional properties for adsorption of AHMIs. The efficiency of SDAs developed using these procedures depends on the botanical source of the native starch base, porosity and structural stability of the derivative (i.e. degree of cross-linking), substituted functional group(s), degree of substitution and the steric/conformation effects of the substituted groups. Many works have been done to optimize these factors, and this review highlighted some of the tailored procedures and the results obtained.
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Affiliation(s)
| | - Ebun Oladele
- Federal University of Technology, Akure, Nigeria
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González-López ME, Laureano-Anzaldo CM, Pérez-Fonseca AA, Arellano M, Robledo-Ortíz JR. Chemically Modified Polysaccharides for Hexavalent Chromium Adsorption. SEPARATION AND PURIFICATION REVIEWS 2020. [DOI: 10.1080/15422119.2020.1783311] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
| | | | | | - Martín Arellano
- Departamento de Ingeniería Química, CUCEI, Universidad De Guadalajara, Jalisco, México
| | - Jorge Ramón Robledo-Ortíz
- Departamento de Madera, Celulosa y Papel, CUCEI, Universidad de Guadalajara, Zapopan, Jalisco, México
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Shafizadeh F, Taghizadeh M, Hassanpour S. Preparation of a novel magnetic Pd(II) ion-imprinted polymer for the fast and selective adsorption of palladium ions from aqueous solutions. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:18493-18508. [PMID: 31044383 DOI: 10.1007/s10924-016-0929-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2018] [Accepted: 04/22/2019] [Indexed: 05/27/2023]
Abstract
A novel magnetic ion-imprinted polymer with high accessibility to palladium ions was synthesized via co-precipitation polymerization. Accordingly, a ternary complex composed of PdCl2 as an imprinting ion, 8-aminoquinoline (AQ) as a ligand, and 4-vinyl pyridine (4-VP) as a complexing monomer was applied to Fe3O4@SiO2 as magnetic core, followed by precipitation polymerization using 2-hydroxyethyl methacrylate (2-HEMA) as a co-monomer, ethylene glycol dimethacrylate (EGDMA) as the crosslinker, and 2,2-azobisisobutyronitrile (AIBN) as an initiator in the presence of 2-methoxyethanol as a solvent. The palladium ions were leached out by a solution containing 50% (v/v) HCl. The synthesized polymer was characterized physically and morphologically using different techniques. In order to assess the conditions required for adsorption, as well as the selectivity and reusability, batch adsorption experiments were carried out. The experiments exhibited that the maximum adsorption capacity was about 65.75 mg g-1 at 25 °C, while the pH solution and the adsorbent dose were 4 and 1 g L-1, respectively. Kinetic studies of experimental data demonstrated that they correspond very much to the pseudo-second-order kinetic model. The development of the Langmuir and Freundlich isothermal models on the equilibrium data proved to correspond well to the Langmuir isotherm model. Interferences studies of the magnetic polymer demonstrated higher affinity and discernment for palladium ions than other co-existing ions in the solutions. Spontaneous (ΔG < 0) and exothermic (ΔH < 0) behavior of the adsorption process is confirmed by thermodynamic studies. In addition, the affinity of the spent polymer has not been dramatically reduced over at least five regeneration cycles.
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Affiliation(s)
- Fatemeh Shafizadeh
- Chemical Engineering Department, Babol Noshirvani University of Technology, P.O. Box 484, Babol, 4714871167, Iran
| | - Majid Taghizadeh
- Chemical Engineering Department, Babol Noshirvani University of Technology, P.O. Box 484, Babol, 4714871167, Iran.
| | - Samaneh Hassanpour
- Chemical Engineering Department, Babol Noshirvani University of Technology, P.O. Box 484, Babol, 4714871167, Iran
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Yamada K, Ishiguro Y, Kimura Y, Asamoto H, Minamisawa H. Two-step grafting of 2-hydroxyethyl methacrylate (HEMA) and 2-(dimethylamino)ethyl methacrylate (DMAEMA) onto a polyethylene plate for enhancement of Cr(VI) ion adsorption. ENVIRONMENTAL TECHNOLOGY 2019; 40:855-869. [PMID: 29168932 DOI: 10.1080/09593330.2017.1409274] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Accepted: 11/19/2017] [Indexed: 06/07/2023]
Abstract
Polyethylene (PE) plates grafted with a neutral monomer, 2-hydroxyethyl methacrylate (HEMA), and a cationic monomer, 2-(dimethylamino)ethyl methacrylate (DMAEMA), (PE-g-PHEMA)-g-PDMAEMA plates were prepared by the two-step photografting. The Cr(VI) ion adsorption behavior of the (PE-g-PHEMA)-g-PDMAEMA plates was investigated as a function of the amounts of grafted HEMA, amount of grafted DMAEMA, initial pH value, and temperature. The adsorption capacity of the DMAEMA-grafted PE (PE-g-PDMAEMA) and (PE-g-PHEMA)-g-PDMAEMA plates had the maximum value at the initial pH value of 3.0, independent of the temperature. The adsorption capacity of (PE-g-PHEMA)-g-PDMAEMA plates increased with the amount of grafted HEMA (GHEMA) in the first-step grafting. The increase in the water absorptivity of the grafted layers and thereby the increase in the degree of protonation of dimethylamino groups on grafted PDMAEMA chains were found to lead to the increase in the adsorption capacity. This adsorption capacity was higher than or comparable to those of other polymeric adsorbents for Cr(VI) ions. The Cr(VI) ion adsorption behavior on both PE-g-DMAEMA and (PE-g-PHEMA)-g-PDMAEMA plates obeyed the mechanism of the pseudo-second-order kinetic model and was well expressed by Langmuir isotherm. The high values of the Langmuir constant suggest that the adsorption of Cr(VI) ions occurs through an electrostatic interaction between protonated dimethylamino groups on grafted PDMAEMA chains and HCrO4- ions. Cr(VI) ions were successfully desorbed from PE-g-PDMAEMA and (PE-g-PHEMA)-g-PDMAEMA plates in eluents such as NaCl, NaCl containing NaOH, NH4Cl, NH4Cl containing NaOH, and NaOH.
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Affiliation(s)
- Kazunori Yamada
- a Department of Applied Molecular Chemistry , College of Industrial Technology, Nihon University , Narashino , Japan
| | - Yohei Ishiguro
- a Department of Applied Molecular Chemistry , College of Industrial Technology, Nihon University , Narashino , Japan
| | - Yuji Kimura
- b Department of Basic Science , College of Industrial Technology, Nihon University , Narashino , Japan
| | - Hiromichi Asamoto
- b Department of Basic Science , College of Industrial Technology, Nihon University , Narashino , Japan
| | - Hiroaki Minamisawa
- b Department of Basic Science , College of Industrial Technology, Nihon University , Narashino , Japan
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Lalita, Singh AP, Sharma RK. Selective sorption of Fe(II) ions over Cu(II) and Cr(VI) ions by cross-linked graft copolymers of chitosan with acrylic acid and binary vinyl monomer mixtures. Int J Biol Macromol 2017; 105:1202-1212. [PMID: 28757421 DOI: 10.1016/j.ijbiomac.2017.07.163] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Revised: 06/25/2017] [Accepted: 07/26/2017] [Indexed: 01/31/2023]
Abstract
Low-cost and environment-friendly polymeric adsorbents for sorption of heavy metal ions were synthesized by simultaneous graft copolymerization and cross-linking of acrylic acid alone and with comonomers glycidyl methacrylate, acrylamide and acrylonitrile onto chitosan using free radical initiator and cross-linker in aqueous medium. Structural aspects of cross-linked graft copolymers have been characterized by FTIR, SEM, TGA/DTA, XRD and swelling behavior at pH 2.2, 7.0 and 9.4. An attempt has been made to study sorption of Cr(VI), Cu(II) and Fe(II) ions on cross-linked graft copolymers by equilibration method and to establish a relationship between structural aspects of graft copolymers and metal ion uptake efficiency and selectivity. Solutions of individual ions were used for non-competitive sorption onto synthesized bio-adsorbents as a function of change in contact time, temperature, pH and metal ion concentration in feed. Competitive sorption investigation was performed from an aqueous solution of ternary metal ions by batch equilibration at 25°C and at 7.0pH. Cross-linked graft copolymers showed better results than unmodified chitosan and showed preferential sorption of Fe(II) ions than Cu(II) and Cr(VI) ions.
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Affiliation(s)
- Lalita
- IK Gujral Punjab Technical University, Kapurthala, Punjab, 144601 India; University Institute of Sciences, Chemistry Department, Chandigarh University, Gharuan, Mohali, Punjab, 140413 India
| | - Anirudh P Singh
- IK Gujral Punjab Technical University, Kapurthala, Punjab, 144601 India
| | - Rajeev Kr Sharma
- Department of Chemistry, DAV College, Jalandhar, Punjab, 144008 India.
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Fu L, Deng W, Liu L, Peng Y. Nanopalladium on polyethylenimine-grafted starch: An efficient and ecofriendly heterogeneous catalyst for Suzuki-Miyaura coupling and transfer hydrogenation reactions. Appl Organomet Chem 2017. [DOI: 10.1002/aoc.3853] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Lixia Fu
- Shanghai Key Laboratory of Chemical Biology, School of Pharmacy; East China University of Science and Technology; Shanghai 200237 People's Republic of China
| | - Wenxiu Deng
- Shanghai Key Laboratory of Chemical Biology, School of Pharmacy; East China University of Science and Technology; Shanghai 200237 People's Republic of China
| | - Lujie Liu
- Shanghai Key Laboratory of Chemical Biology, School of Pharmacy; East China University of Science and Technology; Shanghai 200237 People's Republic of China
| | - Yanqing Peng
- Shanghai Key Laboratory of Chemical Biology, School of Pharmacy; East China University of Science and Technology; Shanghai 200237 People's Republic of China
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Fu L, Peng Y. Isocyanate-functionalized starch as biorenewable backbone for the preparation and application of poly(ethylene imine) grafted starch. MONATSHEFTE FUR CHEMIE 2017. [DOI: 10.1007/s00706-016-1913-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Asamoto H, Kimura Y, Ishiguro Y, Minamisawa H, Yamada K. Use of polyethylene films photografted with 2-(dimethylamino)ethyl methacrylate as a potential adsorbent for removal of chromium (VI) from aqueous medium. J Appl Polym Sci 2016. [DOI: 10.1002/app.43360] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Hiromichi Asamoto
- Department of Basic Science, College of Industrial Technology; Nihon University; 2-11-1 Shin-Ei Narashino 275-8576 Japan
| | - Yuji Kimura
- Department of Applied Polymer Science, College of Industrial Technology; Nihon University; 1-2-1 Izumi-Cho Narashino 275-8575 Japan
| | - Yohei Ishiguro
- Department of Applied Polymer Science, College of Industrial Technology; Nihon University; 1-2-1 Izumi-Cho Narashino 275-8575 Japan
| | - Hiroaki Minamisawa
- Department of Basic Science, College of Industrial Technology; Nihon University; 2-11-1 Shin-Ei Narashino 275-8576 Japan
| | - Kazunori Yamada
- Department of Applied Polymer Science, College of Industrial Technology; Nihon University; 1-2-1 Izumi-Cho Narashino 275-8575 Japan
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He C, Liu X, Shi J, Ma C, Pan H, Li G. Anionic starch-induced Cu-based composite with flake-like mesostructure for gas-phase propanal efficient removal. J Colloid Interface Sci 2015; 454:216-25. [DOI: 10.1016/j.jcis.2015.05.021] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Revised: 05/01/2015] [Accepted: 05/11/2015] [Indexed: 10/23/2022]
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Goud VD, DSouza R, Valiyaveettil S. Solution processable polyamines via click chemistry for water purification. RSC Adv 2015. [DOI: 10.1039/c5ra04155d] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Highly stable amine functionalized polystyrenes were prepared and used for the removal of dissolved pollutants from water.
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Affiliation(s)
- Vanga Devendar Goud
- Department of Chemistry
- National University of Singapore
- Singapore 117 543
- Singapore
| | - Roshan DSouza
- Department of Chemistry
- National University of Singapore
- Singapore 117 543
- Singapore
| | - Suresh Valiyaveettil
- Department of Chemistry
- National University of Singapore
- Singapore 117 543
- Singapore
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Abstract
Chromium is extremely toxic and considered a priority pollutant. It is compulsory to control the discharge of chromium compounds into aquatic systems in order to prevent severe environmental problems. Among all the treatment methods, adsorption has been proved to be a substantial method for the removal of chromium from wastewater. Recently, a variety of starch-based materials have been used as chromium adsorbents. The present review provides the recent development in the sorption capacities of starch-based sorbents for chromium, new starch-based materials and their advantages for the removal of chromium from the wastewater. Moreover, the adsorption mechanisms of Cr (III) or Cr (VI) on starch-based adsorbents are reviewed, and the sorption efficiency and capacities of starch-based adsorbents are compared with that of other low cost adsorbent materials. The primary objective is to provide the recent information about the starch-based materials as absorbents, and propose that the starch-based microsphere materials as absorbents will develop greater function in removal of chromium from wastewater in future.
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Investigation on structure and properties of cobalt(II)/polyesterurethane metallopolymer films. JOURNAL OF POLYMER RESEARCH 2012. [DOI: 10.1007/s10965-012-0018-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Chan WC, Cheng CW. Mass transport process for adsorption of metal ions onto a new type adsorbent poly(vinyl alcohol)(PVA)/peat/clay composite bead. JOURNAL OF POLYMER RESEARCH 2012. [DOI: 10.1007/s10965-012-9964-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Equilibrium and kinetics studies of Cu(II) ions adsorption on polyamidoamine dendrimer starch. RESEARCH ON CHEMICAL INTERMEDIATES 2012. [DOI: 10.1007/s11164-012-0557-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Maksin DD, Nastasović AB, Milutinović-Nikolić AD, Suručić LT, Sandić ZP, Hercigonja RV, Onjia AE. Equilibrium and kinetics study on hexavalent chromium adsorption onto diethylene triamine grafted glycidyl methacrylate based copolymers. JOURNAL OF HAZARDOUS MATERIALS 2012; 209-210:99-110. [PMID: 22284173 DOI: 10.1016/j.jhazmat.2011.12.079] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2011] [Revised: 12/14/2011] [Accepted: 12/28/2011] [Indexed: 05/31/2023]
Abstract
Two porous and one non-porous crosslinked poly(glycidyl methacrylate-co-ethylene glycol dimethacrylate) [abbreviated PGME] were prepared by suspension copolymerization and functionalized with diethylene triamine [abbreviated PGME-deta]. Samples were characterized by elemental analysis, mercury porosimetry, scanning electron microscopy with energy-dispersive X-ray spectroscopy, and transmission electron microscopy. Kinetics of Cr(VI) sorption by PGME-deta were investigated in batch static experiments, in the temperature range 25-70°C. Sorption was rapid, with the uptake capacity higher than 80% after 30 min. Sorption behavior and rate-controlling mechanisms were analyzed using five kinetic models (pseudo-first order, pseudo-second order, Elovich, intraparticle diffusion and Bangham model). Kinetic studies showed that Cr(VI) adsorption adhered to the pseudo-second-order model, with definite influence of pore diffusion. Equilibrium data was tested with Langmuir, Freundlich and Tempkin adsorption isotherm models. Langmuir model was the most suitable indicating homogeneous distribution of active sites on PGME-deta and monolayer sorption. The maximum adsorption capacity from the Langmuir model, Q(max), at pH 1.8 and 25°C was 143 mg g(-1) for PGME2-deta (sample with the highest amino group concentration) while at 70°C Q(max) reached the high value of 198 mg g(-1). Thermodynamic parameters revealed spontaneous and endothermic nature of Cr(VI) adsorption onto PGME-deta.
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Affiliation(s)
- Danijela D Maksin
- University of Belgrade, Vinča Institute of Nuclear Sciences, P.O. Box 522, Belgrade, Serbia
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Bayramoglu G, Arica MY. Synthesis of Cr(VI)-imprinted poly(4-vinyl pyridine-co-hydroxyethyl methacrylate) particles: its adsorption propensity to Cr(VI). JOURNAL OF HAZARDOUS MATERIALS 2011; 187:213-221. [PMID: 21272995 DOI: 10.1016/j.jhazmat.2011.01.022] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2010] [Revised: 12/07/2010] [Accepted: 01/05/2011] [Indexed: 05/30/2023]
Abstract
The aim of this study is to prepare ion-imprinted polymers, which can be used for the selective removal of Cr(VI) anions from aqueous media. 4-Vinyl pyridine (4-VP) was used as functional monomer. The Cr(VI)-imprinted poly(4-vinyl pyridine-co-2-hydroxyethyl methacrylate), poly(VP-HEMA), particles were prepared by bulk polymerization. The Cr(VI)-imprinted polymer particles were grained from the bulk polymer, and the template ions (i.e., Cr(VI)) were removed using thiourea (0.5%, v/v) in 0.5M HCl. The Cr(VI)-imprinted polymer contained 21.4 μmol 4-VP/g polymers. The specific surface area of the IIP2 particles was found to be 34.5m(2)/g (size range of 75-150 μm), and the swelling ratio was about to 108%. The effect of initial concentration of Cr(VI) anions, the adsorption rate and the pH of the medium on adsorption capacity of Cr(VI)-imprinting polymer were studied. The maximum experimental adsorption capacity was 3.31 mmol Cr(VI)/g polymer. Under competitive condition, the adsorption capacity of Cr(VI)-imprinted particles for Cr(VI) is 13.8 and 11.7 folds greater than that of the Cr(III) and Ni(II) ions, respectively. The first- and second order kinetics models were estimated on the basis of comparative analysis of the corresponding rate parameters, equilibrium capacity and correlation coefficients. The Langmuir adsorption isotherm model was well described the Cr(VI)-imprinted system and the maximum adsorption capacity (Q(max)) was found to be 3.42 mmol/g. Moreover, the reusability of the poly(VP-HEMA) particles was tested for several times and no significant loss in adsorption capacity was observed.
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Affiliation(s)
- Gulay Bayramoglu
- Biochemical Processing and Biomaterial Research Laboratory, Faculty of Arts and Sciences, Gazi University, 06500 Ankara, Turkey. g
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Wang Z, Xiang B, Cheng R, Li Y. Behaviors and mechanism of acid dyes sorption onto diethylenetriamine-modified native and enzymatic hydrolysis starch. JOURNAL OF HAZARDOUS MATERIALS 2010; 183:224-232. [PMID: 20675047 DOI: 10.1016/j.jhazmat.2010.07.015] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2010] [Revised: 07/01/2010] [Accepted: 07/02/2010] [Indexed: 05/26/2023]
Abstract
In this paper, different starches were modified by diethylenetriamine. The native starch reacted with diethylenetriamine giving CAS, whereas the enzymatic hydrolysis starch was modified by diethylenetriamine producing CAES. Adsorption capacities of CAES for four acid dyes, namely, Acid orange 7 (AO7), Acid orange 10 (AO10), Acid green 25 (AG25) and Acid red 18 (AR18) have been determined to be 2.521, 1.242, 1.798 and 1.570 mmol g(-1), respectively. In all cases, CAES has exhibited higher sorption ability than CAS, and the increment for these dyes took the sequence of AO7 (0.944 mmol g(-1))>AO10 (0.592 mmol g(-1))>AR18 (0.411 mmol g(-1))>AG25 (0.047 mmol g(-1)). Sorption kinetics and isotherms analysis showed that these sorption processes were better fitted to pseudo-second-order equation and Langmuir equation. Chemical sorption mechanisms were confirmed by studying the effects of pH, ionic strength and hydrogen bonding. Thermodynamic parameters of these dyes onto CAES and CAS were also observed and it indicated that these sorption processes were exothermic and spontaneous in nature.
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Affiliation(s)
- Zuohua Wang
- Department of Chemistry, Tongji University, Shanghai 200092, China
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Klimaviciute R, Bendoraitiene J, Rutkaite R, Zemaitaitis A. Adsorption of hexavalent chromium on cationic cross-linked starches of different botanic origins. JOURNAL OF HAZARDOUS MATERIALS 2010; 181:624-632. [PMID: 20605323 DOI: 10.1016/j.jhazmat.2010.05.058] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2010] [Revised: 05/14/2010] [Accepted: 05/14/2010] [Indexed: 05/29/2023]
Abstract
The influence of origin of native starch used to obtain cationic cross-linked starch (CCS) on the adsorption of Cr(VI) onto CCS has been investigated. CCS granule size is influenced by the botanic source of native starch. The equilibrium adsorption of Cr(VI) onto CCS was described by the Langmuir, Freundlich, Dubinin-Radushkevich and Temkin models. The more equal the adsorption energy of the quaternary ammonium groups in CCS granule as indicated by low value of change of Temkin adsorption energy DeltaE(T) the greater amount of Cr(VI) was adsorbed onto CCS. The value of DeltaE(T) decreased and sorption capacity of CCS increased with the decrease of CCS granule size and with the increase of number of amorphous regions in CCS granules. The affinity of dichromate anions increases and adsorption proceeds more spontaneously when Cr(VI) is adsorbed onto more amorphous CCS. Adsorption process of Cr(VI) onto such CCS is more exothermic and order of system undergoes major changes during adsorption. After the adsorption on CCS Cr(VI) could be regenerated by incineration at temperature of 800 degrees C.
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Affiliation(s)
- Rima Klimaviciute
- Faculty of Chemical Technology, Kaunas University of Technology, Kaunas, Lithuania.
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