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1. Adsorption and Transport of Arsenic(V) in Experimental Subsurface Systems

Author:
L. Elizabeth Williams; Mark O. Barnett; Timothy A. Kramer; Joel G. Melville
Source:
Journal of environmental quality 2003 v.32 no.3 pp. 841-850
ISSN:
1537-2537
Subject:
adsorption; arsenic; equations; ferric oxide; laboratory experimentation; models; pH; soil; sorption isotherms
Abstract:
... The adsorption and transport of As(V) in a heterogeneous, iron oxide–containing soil was investigated in batch and column laboratory experiments. The As(V) adsorbed rapidly to the soil over the first 48 h, but continued to adsorb slowly over the next several weeks, clearly indicating the potential for rate-limited transport. The equilibrium As(V) adsorption isotherm was markedly nonlinear, further ...
DOI:
10.2134/jeq2003.8410
PubMed:
12809285

2. Adsorption and removal of arsenic (V) using crystalline manganese (II,III) oxide: Kinetics, equilibrium, effect of pH and ionic strength

Author:
Kamel Babaeivelni; Amid P. Khodadoust; Dorin Bogdan
Source:
Journal of environmental science and health 2014 v.49 no.13 pp. 1462-1473
ISSN:
1532-4117
Subject:
adsorption; alkalinity; aluminum oxide; arsenic; bicarbonates; environmental health; equations; groundwater; ionic strength; ions; manganese; pH; sorption isotherms; surface area
Abstract:
... Manganese (II,III) oxide (Mn ₃O ₄) crystalline powder was evaluated as a potential sorbent for removal of arsenic (V) from water. Adsorption isotherm experiments were carried out to determine the adsorption capacity using de-ionized (DI) water, a synthetic solution containing bicarbonate alkalinity, and two natual groundwater samples. Adsorption isotherm data followed the Langmuir and Freundlich e ...
DOI:
10.1080/10934529.2014.937160

3. Adsorption kinetics, capacity and mechanism of arsenate and phosphate on a bifunctional TiO₂–Fe₂O₃ bi-composite

Author:
Mitch D’Arcy; Dominik Weiss; Michael Bluck; Ramon Vilar
Source:
Journal of colloid and interface science 2011 v.364 no.1 pp. 205-212
ISSN:
0021-9797
Subject:
adsorbents; adsorption; arsenates; arsenic; equations; groundwater; models; pH; phosphates; titanium dioxide
Abstract:
... Mixed oxide TiO₂–Fe₂O₃ bi-composites have been recognised as efficient and economical sorbents with great promise for arsenic removal from groundwater. In this study, we use a fast, simple and inexpensive synthesis method for this type of bi-composite and assess its adsorption performance. The kinetics of arsenate and phosphate adsorption onto the bi-composite are determined, demonstrating rapid a ...
DOI:
10.1016/j.jcis.2011.08.023

4. Adsorption of As(III) on chitosan-Fe-crosslinked complex (Ch-Fe)

Author:
Helen Helena dos Santos; Carla Albertina Demarchi; Clovis Antonio Rodrigues; Jean Marc Greneche; Nataliya Nedelko; Anna Ślawska-Waniewska
Source:
Chemosphere 2011 v.82 no.2 pp. 278-283
ISSN:
0045-6535
Subject:
adsorption; arsenic; chitosan; crosslinking; equations; iron; kinetics; models; pH; redox reactions; sorption isotherms; spectroscopy
Abstract:
... It was reported the adsorption of As(III) on the surface of the chitosan-Fe-crosslinked complex. Theoretical correlation of the experimental equilibrium adsorption data for As(III)/Ch-Fe system is best explained by the non-linearized form Langmuir–Freundlich isotherm model. At optimum conditions, pH 9.0, the maximum adsorption capacity, calculated using the Langmuir–Freundlich isotherm model was 1 ...
DOI:
10.1016/j.chemosphere.2010.09.033
PubMed:
20943252

5. Adsorption of Cr(VI) and As(V) ions by modified magnetic chitosan chelating resin

Author:
Y.G. Abou El-Reash; M. Otto; I.M. Kenawy; A.M. Ouf
Source:
International journal of biological macromolecules 2011 v.49 no.4 pp. 513-522
ISSN:
0141-8130
Subject:
crosslinking; temperature; X-ray diffraction; sodium hydroxide; chitosan; equations; arsenic; models; glutaraldehyde; scanning electron microscopy; pH; Fourier transform infrared spectroscopy; sorption isotherms; mass transfer; chromium; metal ions; anthranilic acid; desorption; adsorption
Abstract:
... Cross-linked magnetic chitosan anthranilic acid glutaraldehyde Schiff's base (CAGS) was prepared for adsorption of both As(V) and Cr(VI) ions and their determination by ICP-OES. Prepared cross-linked magnetic CAGS was investigated by means of SEM, FTIR, wide angle X-ray diffraction (WAXRD) and TGA analysis. The adsorption properties of cross-linked magnetic CAGS resin toward both As(V) and Cr(VI) ...
DOI:
10.1016/j.ijbiomac.2011.06.001

6. Adsorption of arsenate from aqueous solution by ferric oxide-impregnated Dowex Marathon MSA anion exchange resin: application of non-linear isotherm modeling and thermodynamic studies

Author:
Sujitra Tandorn; Orn-anong Arqueropanyo; Wimol Naksata; Ponlayuth Sooksamiti; Ingon Chaisri
Source:
Environmental earth sciences 2019 v.78 no.5 pp. 136
ISSN:
1866-6280
Subject:
Gibbs free energy; adsorbents; adsorption; anion exchange resins; aqueous solutions; arsenates; arsenic; endothermy; enthalpy; entropy; equations; models; pH; regression analysis; sorption isotherms; temperature
Abstract:
... The characteristic of adsorption of As(V) onto ferric oxide-impregnated anion resin Dowex marathon MSA (FO-Dowex) was investigated. Batch adsorption experiment was studied as a function of pH, contact time, initial As(V) concentration, and temperature. The results revealed that the adsorption of As(V) onto FO-Dowex was highly pH-dependent and that the equilibrium time was attained within 360 min. ...
DOI:
10.1007/s12665-019-8138-y

7. Adsorption of arsenic from micro-polluted water by an innovative coal-based mesoporous activated carbon in the presence of co-existing ions

Author:
Xu-Jin Gong; Wei-Guang Li; Duo-Ying Zhang; Wen-Biao Fan; Xin-Ran Zhang
Source:
International Biodeterioration & Biodegradation 2015 v.102 pp. 256-264
ISSN:
0964-8305
Subject:
absorption; activated carbon; adsorbents; adsorption; anions; arsenic; chromium; equations; iodine; methylene blue; pH; phosphates; porosity; porous media; sulfates
Abstract:
... A novel, multi-step procedure was introduced to prepare an innovative coal-based activated carbon (M-NCPAC) in the present work. The adsorption characteristics of As(III)/As(V) ions in low concentrations (0.5 mg/L) from an As(III)/As(V) system were studied at 4 °C. The effects of co-existing Cr(VI) on arsenic adsorption by M-NCPAC were also determined as a function of pH, contact time and adsorben ...
DOI:
10.1016/j.ibiod.2015.01.007

8. Adsorption of arsenic on multiwall carbon nanotube–zirconia nanohybrid for potential drinking water purification

Author:
Susana Addo Ntim; Somenath Mitra
Source:
Journal of colloid and interface science 2012 v.375 no.1 pp. 154-159
ISSN:
0021-9797
Subject:
absorption; adsorption; arsenic; carbon; drinking water; equations; iron oxides; pH; sorption isotherms; water purification
Abstract:
... The adsorptive removal of arsenic from water using a multiwall carbon nanotube–zirconia nanohybrid (MWCNT–ZrO₂) is presented. The MWCNT–ZrO₂ with 4.85% zirconia was effective in meeting the drinking water standard levels of 10μgL⁻¹. The absorption capacity of the composite were 2000μgg⁻¹ and 5000μgg⁻¹ for As(III) and As(V) respectively, which were significantly higher than those reported previousl ...
DOI:
10.1016/j.jcis.2012.01.063
PubMed:
22424815
PubMed Central:
PMC3321230

9. Adsorptive Removal of Arsenic and Mercury from Aqueous Solutions by Eucalyptus Leaves

Author:
Mahmood Alimohammadi; Zhyar Saeedi; Bahman Akbarpour; Hassan Rasoulzadeh; Kaan Yetilmezsoy; Mohammad A. Al-Ghouti; Majeda Khraisheh; Gordon McKay
Source:
Water, air, and soil pollution 2017 v.228 no.11 pp. 429
ISSN:
0049-6979
Subject:
Eucalyptus; adsorbents; adsorption; aqueous solutions; arsenic; equations; heavy metals; kinetics; leaves; mercury; models; pH; response surface methodology; sorption isotherms
Abstract:
... The study is a first-time investigation into the use of Eucalyptus leaves as a low-cost herbal adsorbent for the removal of arsenic (As) and mercury (Hg) from aqueous solutions. The adsorption capacity and efficiency were studied under various operating conditions within the framework of response surface methodology (RSM) by implementing a four-factor, five-level Box–Wilson central composite desig ...
DOI:
10.1007/s11270-017-3607-y

10. Adsorptive removal of arsenic from water by an iron–zirconium binary oxide adsorbent

Author:
Zongming Ren; Gaosheng Zhang; J. Paul Chen
Source:
Journal of colloid and interface science 2011 v.358 no.1 pp. 230-237
ISSN:
0021-9797
Subject:
Fourier transform infrared spectroscopy; adsorbents; adsorption; anions; arsenates; arsenic; arsenites; coprecipitation; equations; groundwater; human health; ionic strength; pH; risk; surface area; zeta potential
Abstract:
... Arsenate and arsenite may exist simultaneously in groundwater and have led to a greater risk to human health. In this study, an iron–zirconium (Fe–Zr) binary oxide adsorbent for both arsenate and arsenite removal was prepared by a coprecipitation method. The adsorbent was amorphous with a specific surface area of 339m²/g. It was effective for both As(V) and As(III) removal; the maximum adsorption ...
DOI:
10.1016/j.jcis.2011.01.013

11. Arsenate Adsorption by Unsaturated Alluvial Sediments

Author:
Sabine Goldberg; Donald L. Suarez
Source:
Soil Science Society of America journal 2013 v.77 no.3 pp. 782-791
ISSN:
0361-5995
Subject:
adsorption; arsenates; arsenic; basins; capacitance; drinking water; equations; groundwater; groundwater recharge; minerals; pH; phosphates; prediction; regression analysis; remediation; sediments; soil; California; Mojave Desert
Abstract:
... Arsenic can occur naturally in excess of drinking water standards. Earlier a field-scale recharge pond experiment in the Antelope Valley ground water basin, Mohave Desert, California, was performed to determine the effectiveness of naturally occurring minerals in the unsaturated zone to treat high As water. The extent to which the remediation can be continued on any site is unknown and depends on ...
DOI:
10.2136/sssaj2012.0322

12. Arsenate adsorption on three types of granular schwertmannite

Author:
Xiaomin Dou; Dinesh Mohan; Charles U. Pittman
Source:
Water research 2013 v.47 pp. 2938-2948
ISSN:
0043-1354
Subject:
adsorbents; adsorption; anions; arsenic; coatings; drinking water; equations; extrusion; granules; heavy metals; humic acids; landfills; leaching; pH; porosity; sodium hydroxide; toxicity; water pollution
Abstract:
... Schwertmannite was synthesized on a 2 m3-scale and fabricated to irregular, cylindrical and spherical shape granules using drum granulation, extrusion and spray coating, respectively. The granules were systematically evaluated for As(V) removal from drinking water in terms of both performance and safety. The irregular and cylindrical shape granules (IS and CS) had larger schwertmannite loadings, h ...
DOI:
10.1016/j.watres.2013.01.035
PubMed:
23566332

13. Arsenate–Ferrihydrite Systems from Minutes to Months: A Macroscopic and IR Spectroscopic Study of an Elusive Equilibrium

Author:
Swedlund Peter J.; Holtkamp Hannah; Song Yantao; Daughney Christopher J.
Source:
Environmental Science & Technology 2014 v.48 no.5 pp. 2759-2765
ISSN:
1520-5851
Subject:
arsenic; equations; ferrihydrite; models; pH; sorption; spectral analysis
Abstract:
... Sorption by ferrihydrite is an important control on As(V) concentrations in many oxic aquatic systems. There are significant discrepancies in reported sorption constants (log(KAₛ)), which presents a problem for quantifying and understanding this important system. A review of reported ferrihydrite–As(V) sorption studies indicated a positive correlation between reaction time used in the experiments ...
DOI:
10.1021/es404742c

14. Arsenic biosorption using pretreated biomass of psychrotolerant Yersinia sp. strain SOM-12D3 isolated from Svalbard, Arctic

Author:
Somayeh Asadi Haris; Wahid Ali Hamood Altowayti; Zaharah Ibrahim; Shafinaz Shahir
Source:
Environmental science and pollution research international 2018 v.25 no.28 pp. 27959-27970
ISSN:
0944-1344
Subject:
Fourier transform infrared spectroscopy; Yersinia; acid treatment; adsorption; arsenic; biofilm; biomass; biosorbents; biosorption; desorption; equations; hydrochloric acid; lakes; models; pH; psychrophilic bacteria; sorption isotherms; water pollution; Arctic region; Norway
Abstract:
... A Gram-negative, arsenite-resistant psychrotolerant bacterial strain, Yersinia sp. strain SOM-12D3, was isolated from a biofilm sample collected from a lake at Svalbard in the Arctic area. To our knowledge, this is the first study on the ability of acid-treated and untreated, non-living biomass of strain SOM-12D3 to absorb arsenic. We conducted batch experiments at pH 7, with an initial As(III) co ...
DOI:
10.1007/s11356-018-2799-z

15. Arsenic contamination and secondary mineral evaluation in mine drainage using integrated acid–base accounting and toxicity characterisation leaching procedure: the case of Obuasi Mine, Ghana

Author:
Gordon Foli; Simon K. Y. Gawu; Prosper M. Nude
Source:
Environmental earth sciences 2015 v.73 no.12 pp. 8471-8486
ISSN:
1866-6280
Subject:
acidification; acidity; alunite; arsenic; drainage; equations; ferrihydrite; goethite; jarosite; leaching; models; monitoring; neutralization; pH; particle size; planning; remediation; toxicity; Ghana
Abstract:
... This study assessed arsenic (As) contamination and the characteristics of secondary minerals in mine drainage using integrated acid–base accounting (ABA) and toxicity characterisation leaching procedure (TCLP), aqueous and solid-phase media monitoring, as well as a textural and mineralogical analysis of tailings material at the Obuasi mine in Ghana. The neutralisation potential and maximum potenti ...
DOI:
10.1007/s12665-014-4006-y

16. Arsenic(III) sorption on nanostructured cerium incorporated manganese oxide (NCMO): A physical insight into the mechanistic pathway

Author:
K. Gupta; S. Bhattacharya; D. Nandi; A. Dhar; A. Maity; A. Mukhopadhyay; D.J. Chattopadhyay; N.R. Ray; P. Sen; U.C. Ghosh
Source:
Journal of colloid and interface science 2012 v.377 no.1 pp. 269-276
ISSN:
0021-9797
Subject:
Fourier transform infrared spectroscopy; arsenic; cerium; desorption; energy; entropy; equations; ion exchange; manganese oxides; models; pH; sorption isotherms
Abstract:
... Arsenic(III) sorption was investigated with nanostructured cerium incorporated manganese oxide (NCMO). The pH between 6.0 and 8.0 was optimized for the arsenic(III) sorption. Kinetics and equilibrium data (pH=7.0±0.2, T=303±1.6K, and I=0.01M) of arsenic(III) sorption by NCMO described, respectively, the pseudo-second order and the Freundlich isotherm equations well. The sorption process was somewh ...
DOI:
10.1016/j.jcis.2012.01.066

17. Arsenic(V) sorption using chitosan/Cu(OH)2 and chitosan/CuO composite sorbents

Author:
Khalid Z. Elwakeel; Eric Guibal
Source:
Carbohydrate polymers 2015 v.134 pp. 190-204
ISSN:
0144-8617
Subject:
adsorbents; aqueous solutions; arsenic; chitosan; cupric oxide; desorption; encapsulation; energy-dispersive X-ray analysis; equations; ions; pH; recycling; scanning electron microscopy; sodium chloride; sorption isotherms; temperature; zeta potential
Abstract:
... The removal of As(V) ions from aqueous solution was carried out using composite sorbents based on chitosan (as the encapsulating material) and Cu(OH)2 or CuO. The sorbents were characterized using SEM, EDX and Zeta potential analysis. Sorption uptake was highly dependent on pH, temperature, initial As(V) concentration and sorbent dosage (SD): the optimum initial pH for arsenic removal was found cl ...
DOI:
10.1016/j.carbpol.2015.07.012

18. Arsenite Sorption and Desorption in Soils

Author:
E. A. Elkhatib; O. L. Bennett; R. J. Wright
Source:
Soil Science Society of America journal 1984 v.48 no.5 pp. 1025-1030
ISSN:
0361-5995
Subject:
A horizons; B horizons; arsenic; arsenites; desorption; equations; iron oxides; pH; regression analysis; soil properties; sorption; sorption isotherms; West Virginia
Abstract:
... A linear form of the Freundlich isotherm was used to describe arsenite [As(III)] sorption by the A and B horizons of five West Virginia soils. Arsenite sorption conformed to the Freundlich isotherm over the entire concentration range for all the soils. Simple correlation coefficients and multiple regression equations were used to relate soil properties to parameters of the Freundlich equation. Iro ...
DOI:
10.2136/sssaj1984.03615995004800050015x

19. As(V) sorption from aqueous solutions using quaternized algal/polyethyleneimine composite beads

Author:
Mohammed F. Hamza; Siming Lu; Khalid A.M. Salih; Hamed Mira; Abdelghaffar S. Dhmees; Toyohisa Fujita; Yuezhou Wei; Thierry Vincent; Eric Guibal
Source:
Science of the total environment 2020 v.719 pp. 137396
ISSN:
0048-9697
Subject:
Fourier transform infrared spectroscopy; X-ray photoelectron spectroscopy; algae; aqueous solutions; arsenic; biomass; calcium chloride; crosslinking; desorption; effluents; energy-dispersive X-ray analysis; equations; gelation; glutaraldehyde; hydrochloric acid; iron; mining; pH; polyethyleneimine; scanning electron microscopy; sorbents; sorption; sorption isotherms; texture; thermogravimetry; titration; zinc
Abstract:
... Composite beads (APEI*), obtained by the controlled interaction of algal biomass with PEI, followed by ionotropic gelation and crosslinking processes using CaCl₂/glutaraldehyde solution, constitute efficient supports for metal binding. The quaternization of algal/PEI beads (Q-APEI*) significantly increases the sorption properties of the composite beads (APEI*) for As(V). The materials are characte ...
DOI:
10.1016/j.scitotenv.2020.137396

20. Assessment of heavy metal pollution and the effect on bacterial community in acidic and neutral soils

Author:
Yongjiao Ma; Yating Wang; Qi Chen; Yongshuang Li; Dongchu Guo; Xiaohong Nie; Xiawei Peng
Source:
Ecological indicators 2020 v.117 pp. 106626
ISSN:
1470-160X
Subject:
antimony; arsenic; bacterial communities; cadmium; chromium; community structure; equations; heavy metals; lead; metal tolerance; pH; pollution; remediation; risk; soil bacteria; zinc; China
Abstract:
... Mining activities have caused heavy metal pollution in Xikuangshan (XKS), China. This work aims to assess heavy metal ecological risk in XKS using a potential ecological risk (PER) index and detect the responses of the soil bacterial community under heavy metal stress at different pH levels. The PER index indicated that antimony (Sb), cadmium (Cd), and arsenic (As) posed the most serious ecologica ...
DOI:
10.1016/j.ecolind.2020.106626