Free Standard AU & NZ Shipping For All Book Orders Over $80!
Register      Login
Environmental Chemistry Environmental Chemistry Society
Environmental problems - Chemical approaches
RESEARCH ARTICLE

Arsenic adsorption onto aluminium-substituted goethite

Ana E. Tufo A , María dos Santos Afonso B and Elsa E. Sileo B C
+ Author Affiliations
- Author Affiliations

A Laboratorio de Química Ambiental, 3iA–ECyT, Universidad de San Martín, Martín de Irigoyen 3100, CP1650, Buenos Aires, Argentina.

B Instituto de Química Física de los Materiales, Medio Ambiente y Energía, Departamento de Química Inorgánica, Analítica y Química Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Pabellón II, Ciudad Universitaria, C1428EHA, Buenos Aires, Argentina.

C Corresponding author. Email: e_sileo@yahoo.es

Environmental Chemistry 13(5) 838-848 https://doi.org/10.1071/EN15154
Submitted: 18 July 2015  Accepted: 21 March 2016   Published: 5 May 2016

Environmental context. Goethite, commonly found in soils, is often partially substituted by Al and strongly influences the mobility of arsenic in the environment. The adsorption of AsV onto goethites with increasing Al substitution was explored, finding that Al incorporation decreases AsV sorption per gram of adsorbent, and that a low level of Al incorporation enhances the adsorption per unit area. Structures of the complexes formed between AsV and the oxy(hydr)oxide surface, at different pH values, are proposed by studying the changes in the surface charges of the adsorbed and non-adsorbed substituted and non-substituted goethites.

Abstract. Aluminium and iron oxy(hydr)oxides in nature are often partially substituted by other elements and strongly influence the mobility of arsenic in the environment. Because goethite is commonly found in soils, and the oxide is easily substituted, in the present work, the adsorption of AsV onto several Al-substituted goethites was explored in order to determine how substitution affects the adsorption process. Three samples with increasing Al content (GAl0, GAl3.78 and GAl7.61) were prepared and fully characterised. The variations in AsV adsorption under different conditions, as well as the variations of the particle surface charge, were analysed. The results showed that the removal capacity of Al-goethites is determined by the Al content. The adsorption maxima per gram followed the trend GAl0> GAl3.78> GAl7.61, indicating that Al incorporation decreases AsV sorption. Adsorption per surface area decreased in the order GAl3.78> GAl0> GAl7.61, implying that a small incorporation of Al enhances the adsorption properties of the surface. The stoichiometry of the probable surface complexes formed with the contaminant at different pH values is proposed, by analysis of all the experimental results obtained before and after AsV adsorption. These surface complexes were used to fit the experimental data with good agreement, and the formation and acidity constants were also estimated.

Additional keywords: Al-goethite, zeta potential.


References

[1]  B. K. Mandal, K. T. Suzuky, Arsenic around the world: a review. Talanta 2002, 58, 201.
Arsenic around the world: a review.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD38XlvVGnsbg%3D&md5=10dd8c00774ad122fd0a7f5c7f99762fCAS | 18968746PubMed |

[2]  D. J. Vaughan, Arsenic. Elements 2006, 2, 71.
Arsenic.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28XkvVarsrg%3D&md5=ef0f27bb75118508cfa2b9d6f5264757CAS |

[3]  P. Ravenscroft, H. Brammer, K. Richard, Arsenic Pollution: a Global Synthesis 2009 (Wiley-Blackwell: Chichester, UK).

[4]  J. Bundschuh, P. Bhattacharya, B. Nath, R. Naidu, J. Ng, L. R. G. Guilherme, L. Q. Ma, K.-W. Kim, J. S. Jean, Arsenic ecotoxicology: the interface between geosphere, hydrosphere and biosphere. J. Hazard. Mater. 2013, 262, 883.
Arsenic ecotoxicology: the interface between geosphere, hydrosphere and biosphere.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3sXhsV2jsrzM&md5=0deb8d6fb21172d00d0419a55f7d0c57CAS | 24055564PubMed |

[5]  S. Wang, C. N. Mulligan, Natural attenuation processes for remediation of arsenic-contaminated soils and groundwater. J. Hazard. Mater. 2006, 138, 459.
Natural attenuation processes for remediation of arsenic-contaminated soils and groundwater.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28XhtFKhtLrP&md5=6836756eefa590defffc02c0f47dc9e4CAS | 17049728PubMed |

[6]  S. Wang, C. N. Mulligan, Occurrence of arsenic contamination in Canada: sources, behavior, and distribution. Sci. Total Environ. 2006, 366, 701.
Occurrence of arsenic contamination in Canada: sources, behavior, and distribution.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28XntVSlurc%3D&md5=050d559abe90a391e13b9308217475a7CAS | 16203025PubMed |

[7]  J. Matschullat, Arsenic in the geosphere – a review. Sci. Total Environ. 2000, 249, 297.
Arsenic in the geosphere – a review.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3cXitlGrtrg%3D&md5=b53e9c49a3677510134b45620f8a3f46CAS | 10813460PubMed |

[8]  P. L. Smedley, D. G. Kinniburgh, A review of the source, behavior and distribution of arsenic in natural waters. Appl. Geochem. 2002, 17, 517.
A review of the source, behavior and distribution of arsenic in natural waters.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD38XhvVSmur0%3D&md5=1a0372fd67d357037569e79869e2bda1CAS |

[9]  S. Dixit, J. G. Hering, Comparison of arsenic(V) and arsenic(III) sorption onto iron oxide minerals: implications for arsenic mobility. Environ. Sci. Technol. 2003, 37, 4182.
Comparison of arsenic(V) and arsenic(III) sorption onto iron oxide minerals: implications for arsenic mobility.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3sXmtFOltr8%3D&md5=968ea3519644b561f821b486a50dd6a9CAS | 14524451PubMed |

[10]  R. S. Oremland, T. R. Kulp, J. S. Blum, S. E. Hoeft, S. Baesman, L. G. Miller, J. F. Stolz, A microbial arsenic cycle in a salt-saturated, extreme environment. Science 2005, 308, 1305.
A microbial arsenic cycle in a salt-saturated, extreme environment.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXks1Ciur8%3D&md5=2188c164eeaa6a6e165f582e32c02d28CAS | 15919992PubMed |

[11]  W. Sun, R. Sierra-Alvarez, L. Milner, R. Oremland, J. A. Field, Arsenite and ferrous iron oxidation linked to chemolithotrophicdenitrification for the immobilization of arsenic in anoxic environments. Environ. Sci. Technol. 2009, 43, 6585.
Arsenite and ferrous iron oxidation linked to chemolithotrophicdenitrification for the immobilization of arsenic in anoxic environments.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXptVCkt70%3D&md5=e3252916612a87d4b1356184b6d8fe27CAS | 19764221PubMed |

[12]  S. Musić, M. Ristic, Sorption of chromium(VI) on hydrous iron oxides. Z. Wasser Abwasser For. 1986, 19, 186.

[13]  S. Musić, M. Ristic, Adsorption of trace elements or radionuclides on hydrous iron oxides. J. Radioanal. Nucl. Chem. 1988, 120, 289.
Adsorption of trace elements or radionuclides on hydrous iron oxides.Crossref | GoogleScholarGoogle Scholar |

[14]  B. C. Barja, M. dos Santos Afonso, Aminomethylphosphonic acid and glyphosate adsorption onto goethite: a comparative study. Environ. Sci. Technol. 2005, 39, 585.
Aminomethylphosphonic acid and glyphosate adsorption onto goethite: a comparative study.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2cXhtVGktLfO&md5=62d3c80288fb82555ad27a44427f08dcCAS | 15707059PubMed |

[15]  J. Aguilar, C. Dorronsoro, E. Fernández, J. Fernández, I. García, F. Martín, M. Sierra, M. Simón, Remediation of As-contaminated soils in the Guadiamar River Basin (SW, Spain). Water Air Soil Pollut. 2007, 180, 109.
Remediation of As-contaminated soils in the Guadiamar River Basin (SW, Spain).Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2sXhsFWisbk%3D&md5=ac7340b1fae381e822b91bb3b94f5419CAS |

[16]  B. A. Manning, S. E. Fendorf, S. Goldberg, Surface structures and stability of arsenic(III) on goethite: spectroscopic evidence for inner-sphere complexes. Environ. Sci. Technol. 1998, 32, 2383.
Surface structures and stability of arsenic(III) on goethite: spectroscopic evidence for inner-sphere complexes.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK1cXksFSrurs%3D&md5=5abbef76409eab97d7f833064f3998f0CAS |

[17]  G. A. Waychunas, B. A. Rea, C. C. Fuller, J. A. Davis, Surface chemistry of ferrihydrite. Part 1. EXAFS studies of the geometry of coprecipitated and adsorbed arsenate. Geochim. Cosmochim. Acta 1993, 57, 2251.
Surface chemistry of ferrihydrite. Part 1. EXAFS studies of the geometry of coprecipitated and adsorbed arsenate.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK3sXltVSjsrc%3D&md5=db2a184df57166a5e10dbfdc8452c628CAS |

[18]  M. L. Pierce, C. M. Moore, Adsorption of arsenite and arsenate on amorphous iron hydroxide. Water Res. 1982, 16, 1247.
Adsorption of arsenite and arsenate on amorphous iron hydroxide.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL38XltFCqtLs%3D&md5=0e6a2d36b7e5de41d48ca180511c68e0CAS |

[19]  S. Fendorf, M. J. Eick, P. Grossl, D. L. Sparks, Arsenate and chromate retention mechanisms on goethite. 1. Surface structure. Environ. Sci. Technol. 1997, 31, 315.
Arsenate and chromate retention mechanisms on goethite. 1. Surface structure.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2sXitVGksQ%3D%3D&md5=2905ef1c5dd397ff7a1b9922238668a1CAS |

[20]  D. M. Sherman, S. R. Randall, Surface complexation of arsenic(V) to iron(III) (hydr)oxides: structural mechanism from ab initio molecular geometries and EXAFS spectroscopy. Geochim. Cosmochim. Acta 2003, 67, 4223.
Surface complexation of arsenic(V) to iron(III) (hydr)oxides: structural mechanism from ab initio molecular geometries and EXAFS spectroscopy.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3sXoslOitr0%3D&md5=dd7dccc352282d7e98aec6554b734de0CAS |

[21]  B. Cancès, F. Juillot, G. Morin, V. Laperche, L. Alvarez, O. Proux, J.-L. Hazemann, G. E. Brown, G. Calas, XAS evidence of AsV association with iron oxyhydroxides in a contaminated soil at a former arsenical pesticide processing plant. Environ. Sci. Technol. 2005, 39, 9398.
XAS evidence of AsV association with iron oxyhydroxides in a contaminated soil at a former arsenical pesticide processing plant.Crossref | GoogleScholarGoogle Scholar | 16475314PubMed |

[22]  G. Morin, Y. Wang, G. Ona-Nguema, F. Juillot, G. Calas, N. Menguy, E. Aubry, J. R. Bargar, G. E. Brown, EXAFS and HRTEM evidence for AsIII-containing surface precipitates on nanocrystalline magnetite: implications for As sequestration. Langmuir 2009, 25, 9119.
EXAFS and HRTEM evidence for AsIII-containing surface precipitates on nanocrystalline magnetite: implications for As sequestration.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXosVGjsbw%3D&md5=7c634608ac038a6233a34cc675d5c062CAS | 19601563PubMed |

[23]  Y. Wang, G. Morin, G. Ona-Nguema, F. Juillot, F. Guyot, G. Calas, G. E. Brown, Evidence for different surface speciation of arsenite and arsenate on green rust: an EXAFS and XANES study. Environ. Sci. Technol. 2010, 44, 109.
Evidence for different surface speciation of arsenite and arsenate on green rust: an EXAFS and XANES study.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXht1Sru7%2FL&md5=defa0b6e13284bb6a8b431e886d929afCAS | 20039740PubMed |

[24]  G. Ona-Nguema, G. Morin, F. Juillot, G. Calas, G. E. Brown, EXAFS analysis of arsenite adsorption onto two-line ferrihydrite, hematite, goethite, and lepidocrocite. Environ. Sci. Technol. 2005, 39, 9147.
EXAFS analysis of arsenite adsorption onto two-line ferrihydrite, hematite, goethite, and lepidocrocite.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXhtFCitLfI&md5=8f8fe8541f33f4cc2c451d190a938d62CAS | 16382936PubMed |

[25]  Y. Wang, G. Morin, G. Ona-Nguema, N. Menguy, F. Juillot, E. Aubry, F. Guyot, G. Calas, G. E. Brown, Arsenite sorption at the magnetite–water interface during aqueous precipitation of magnetite: EXAFS evidence for a new arsenite surface complex. Geochim. Cosmochim. Acta 2008, 72, 2573.
Arsenite sorption at the magnetite–water interface during aqueous precipitation of magnetite: EXAFS evidence for a new arsenite surface complex.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXmt1eisL4%3D&md5=d9d4ebd86c0a40f2c247a3109020c072CAS |

[26]  M. Auffan, J. Rose, O. Proux, D. Borschneck, A. Masion, P. Chaurand, J. L. Hazemann, C. Chaneac, J. P. Jolivet, M. R. Wiesner, A. Van Geen, J. Y. Bottero, Enhanced adsorption of arsenic onto maghemites nanoparticles: AsIII as a probe of the surface structure and heterogeneity. Langmuir 2008, 24, 3215.
Enhanced adsorption of arsenic onto maghemites nanoparticles: AsIII as a probe of the surface structure and heterogeneity.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXhslKgu7Y%3D&md5=d92e9bcb3cef175c9e0e4af6125e5ffcCAS | 18266393PubMed |

[27]  J. G. Catalano, C. Park, P. Fenter, Z. Zhang, Simultaneous inner- and outer-sphere arsenate adsorption on corundum and hematite. Geochim. Cosmochim. Acta 2008, 72, 1986.
Simultaneous inner- and outer-sphere arsenate adsorption on corundum and hematite.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXkt1OrurY%3D&md5=d7da950d3820efae5862e1e9ad780250CAS |

[28]  L. Charlet, G. Morin, J. Rose, Y. Wang, M. Auffan, A. Burnol, A. Fernandez-Martinez, Reactivity at (nano)particle–water interfaces, redox processes, and arsenic transport in the environment. C. R. Geosci. 2011, 343, 123.
Reactivity at (nano)particle–water interfaces, redox processes, and arsenic transport in the environment.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXksFKhs70%3D&md5=8271c8fa572ad316a248f05b69da9c33CAS |

[29]  Y. Gao, A. Mucci, Acid–base reactions, phosphate and arsenate complexation, and their competitive adsorption at the surface of goethite in 0.7 M NaCl solution. Geochim. Cosmochim. Acta 2001, 65, 2361.
Acid–base reactions, phosphate and arsenate complexation, and their competitive adsorption at the surface of goethite in 0.7 M NaCl solution.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3MXkvVWms7k%3D&md5=a8719cc495adc28bef5463c5977d9973CAS |

[30]  D. G. Schulze, U. Schertzmann, The influence of aluminium on iron oxides: XIII. Properties of goethites synthesized in 0.3 M KOH at 25 °C. Clay Miner. 1987, 22, 83.
The influence of aluminium on iron oxides: XIII. Properties of goethites synthesized in 0.3 M KOH at 25 °C.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL2sXktFSlsbc%3D&md5=e7712dfb83fbc34e0c35f0f6fbbff589CAS |

[31]  Y. Masue, R. H. Loeppert, T. A. Kramer, Arsenate and arsenite adsorption and desorption behavior on coprecipitatedaluminium:iron hydroxides. Environ. Sci. Technol. 2007, 41, 837.
Arsenate and arsenite adsorption and desorption behavior on coprecipitatedaluminium:iron hydroxides.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28Xhtlaju7jO&md5=21597b1cb1c61231920faf8e1f8dd76aCAS | 17328191PubMed |

[32]  J. Silva, J. W. V. Mello, M. Gasparon, W. A. P. Abrahão, V. S. T. Ciminelli, T. Jong, The role of Al-goethites on arsenate mobility. Water Res. 2010, 44, 5684.
The role of Al-goethites on arsenate mobility.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXhsVOnsb%2FO&md5=7f0c0455cf22e60288b183dab50a55cdCAS | 20638700PubMed |

[33]  U. Schwertmann, R. M. Cornell, Iron Oxides in the Laboratory, Preparation and Characterization, 2nd edn 2000 (Wiley-VCH: Weinheim, Germany).

[34]  D. Leussing, L. Newman, Spectrophotometric study of the bleaching of ferric thioglycolate. J. Am. Chem. Soc. 1956, 78, 552.
Spectrophotometric study of the bleaching of ferric thioglycolate.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaG28XjvFalsQ%3D%3D&md5=bad0f1fa2848be38fb4199a4122baad9CAS |

[35]  S. Brunauer, P. H. Emmett, E. Teller, Adsorption of gases in multimolecular layers. J. Am. Chem. Soc. 1938, 60, 309.
Adsorption of gases in multimolecular layers.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaA1cXivFaruw%3D%3D&md5=9a1da5d6c43cd4df9be5901f3fcab3cfCAS |

[36]  A. C. Larson, R. B. Von Dreele, General Structure Analysis System (GSAS), Los Alamos National Laboratory Report LAUR 86–748 1996 (Los Alamos, NM, USA).

[37]  B. H. Toby, EXPGUI, a graphical user interface for GSAS. J. Appl. Cryst. 2001, 34, 210.
EXPGUI, a graphical user interface for GSAS.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3MXit1yhsbc%3D&md5=35ee7abea3a8f999e2fe61c411927d73CAS |

[38]  A. Szytuła, A. Burewicz, Z. Dimitrijevic, S. Krasnicki, H. Rzany, J. Todorovic, A. Wanic, W. Wolski, Neutron diffraction studies of α-FeOOH. Phys. Status Solidi B 1968, 26, 429.
Neutron diffraction studies of α-FeOOH.Crossref | GoogleScholarGoogle Scholar |

[39]  P. Thompson, D. E. Cox, J. B. Hastings, Rietveld refinement of Debye–Scherrer synchrotron X-ray data from Al2O3. J. Appl. Cryst. 1987, 20, 79.
Rietveld refinement of Debye–Scherrer synchrotron X-ray data from Al2O3.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL2sXitVGlsbo%3D&md5=6952b44d342bcd37b3411fbdfdef905bCAS |

[40]  V. Lenoble, V. Deluchat, B. Serpaud, J. C. Bollinger, Arsenite oxidation and arsenate determination by the molybdene blue method. Talanta 2003, 61, 267.
Arsenite oxidation and arsenate determination by the molybdene blue method.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3sXotVCms70%3D&md5=c4b8450ca4d29900d71898a633ba96cfCAS | 18969186PubMed |

[41]  W. Stumm, Chemistry of the Solid–Water Interface: Processes at the Mineral–Water and Particle–Water Interface in Natural Systems 1992 (Wiley-VCH: Weinheim, Germany).

[42]  E. Deschamps, V. S. T. Ciminelli, P. G. Weidler, A. Y. Ramos, Arsenic sorption onto soils enriched in Mn and Fe minerals. Clays Clay Miner. 2003, 51, 197.
Arsenic sorption onto soils enriched in Mn and Fe minerals.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3sXjtlyiu7c%3D&md5=220000319885de807e009ebef8fffab6CAS |

[43]  Y. S. Ho, G. McKay, Pseudo second-order model for sorption processes. Process Biochem. 1999, 34, 451.
Pseudo second-order model for sorption processes.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK1MXlt1Omtbk%3D&md5=ea680dd0543896daa4b884ec126ed3dcCAS |

[44]  S. E. O’Reilly, D. G. Strawn, D. L. Sparks, Residence time effect of arsenate adsorption/desorption mechanisms on goethite. Soil Sci. Soc. Am. J. 2001, 65, 67.
Residence time effect of arsenate adsorption/desorption mechanisms on goethite.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3MXhvFSltL4%3D&md5=1ecad5a13a5b098dcd2cdb2f105e386cCAS |

[45]  F. Liu, A. De Cristofaro, A. Violante, Effect of pH, phosphate and oxalate on the adsorption/desorption of arsenate on/from goethite. Soil Sci. 2001, 166, 197.
Effect of pH, phosphate and oxalate on the adsorption/desorption of arsenate on/from goethite.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3MXitlWjs7c%3D&md5=62bc7c5ce3c9b947d937484146e6590dCAS |

[46]  J. Antelo, M. Avena, S. Fiol, R. López, F. Arce, Effects of pH and ionic strength on the adsorption of phosphate and arsenate at the goethite–water interface. J. Colloid Interface Sci. 2005, 285, 476.
Effects of pH and ionic strength on the adsorption of phosphate and arsenate at the goethite–water interface.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXjt1yisL8%3D&md5=167e45116f5720b0a4864d830b92ae2dCAS | 15837462PubMed |

[47]  J. H. Huang, A. Voegelin, S. A. Pombo, A. Lazzaro, J. Zeyer, R. Kretzschmar, Influence of arsenate adsorption to ferrihydrite, goethite, and boehmite on the kinetics of arsenate reduction by Shewanellaputrefaciens strain CN-32. Environ. Sci. Technol. 2011, 45, 7701.
Influence of arsenate adsorption to ferrihydrite, goethite, and boehmite on the kinetics of arsenate reduction by Shewanellaputrefaciens strain CN-32.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXhtVyhu7%2FO&md5=ee0a932841c7985880d65ea3316cf28cCAS | 21819067PubMed |

[48]  C. Hung-Lung, J. Rick, Density function theory: a contemporary perspective for the non-specialist. Int. J. Appl. Math. Comput. Sci. 2015, 2, 123.

[49]  M. Martin, A. Violante, F. Ajmone-Marsan, E. Barberis, Surface interactions of arsenite and arsenate on soil colloids. Soil Sci. Soc. Am. J. 2014, 78, 157.
Surface interactions of arsenite and arsenate on soil colloids.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC2cXjtVSrs7w%3D&md5=63e30be493eab3057f58035e528b89fdCAS |

[50]  B. J. Lafferty, R. H. Loeppert, Methyl arsenic adsorption and desorption behavior on iron oxides. Environ. Sci. Technol. 2005, 39, 2120.
Methyl arsenic adsorption and desorption behavior on iron oxides.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXhtl2nsL8%3D&md5=ec52153b97da1babc7802f1c2af0778bCAS | 15871246PubMed |

[51]  J. Cervini-Silva, Alteration of the surface charge of aluminium goethites by a sulfonic acid buffer. J. Colloid Interface Sci. 2004, 275, 79.
Alteration of the surface charge of aluminium goethites by a sulfonic acid buffer.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2cXktFKktrk%3D&md5=4075aa71e09fe40e8bfd875d1a80f252CAS | 15158383PubMed |

[52]  J. van Schuylenborgh, P. Arens, The electrokinetic behaviour of freshly prepared γ-and α-FeOOH. Recl. Trav. Chim. Pays Bas 1950, 69, 1557.
The electrokinetic behaviour of freshly prepared γ-and α-FeOOH.Crossref | GoogleScholarGoogle Scholar |

[53]  G. Bulut, Ü. Yenial, E. Emiroĝlu, A. Ali Sirkeci, Arsenic removal from aqueous solution using pyrite. J. Clean. Prod. 2014, 84, 526.
Arsenic removal from aqueous solution using pyrite.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3sXhsVSns7vK&md5=3464490cfca67ca8f9e504dc24caa189CAS |

[54]  S. Aredes, B. Klein, M. Pawlik, The removal of arsenic from water using natural iron oxide minerals. J. Clean. Prod. 2013, 60, 71.
The removal of arsenic from water using natural iron oxide minerals.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3sXktlCls70%3D&md5=5dc41a40a36ed5e5974b671120620661CAS |

[55]  X. Dou, Y. Zhang, B. Zhao, X. Wu, Z. Wu, M. Yang, Arsenate adsorption on an Fe–Ce bimetal oxide adsorbent: EXAFS study and surface complexationmodeling. Colloids Surf. A Physicochem. Eng. Asp. 2011, 379, 109.
Arsenate adsorption on an Fe–Ce bimetal oxide adsorbent: EXAFS study and surface complexationmodeling.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXktFKju74%3D&md5=6c4388275dffba7a3e65d3cbb1e32442CAS |

[56]  S. Goldberg, Application of surface complexation models to anion adsorption by natural materials. Environ. Toxicol. Chem. 2014, 33, 2172.
Application of surface complexation models to anion adsorption by natural materials.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC2cXhsFKntrjJ&md5=48bf5a4ac79bed1c5d50189935e40380CAS | 24619924PubMed |

[57]  P. Lakshmipathiraj, B. R. V. Narasimhan, S. Prabhakar, G. BhaskarRaju, Adsorption of arsenate on synthetic goethite from aqueous solutions. J. Hazard. Mater. 2006, 136, 281.
Adsorption of arsenate on synthetic goethite from aqueous solutions.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28XmslWjs7w%3D&md5=af32d4190348a1764d8763ee2092217dCAS | 16442724PubMed |

[58]  D. L. Sparks, Environmental Soil Chemistry 2003 (Academic Press: New York).

[59]  G. P. Jeppu, T. P. Clement, A modified Langmuir–Freundlich isotherm model for simulating pH-dependent adsorption effects. J. Contam. Hydrol. 2012, 129-130, 46.
A modified Langmuir–Freundlich isotherm model for simulating pH-dependent adsorption effects.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC38XjtFKru74%3D&md5=386bbd28f4c0fa3277a01d14b01deb7dCAS | 22261349PubMed |

[60]  M. A. Blesa, A. D. Weisz, P. J. Morando, J. A. Salfity, G. E. Magaz, A. E. Regazzoni, The interaction of metal oxide surfaces with complexing agents dissolved in water. Coord. Chem. Rev. 2000, 196, 31.
The interaction of metal oxide surfaces with complexing agents dissolved in water.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3cXht1Clsb8%3D&md5=71ea62d18cdeac73aac5fcf4b36c7744CAS |

[61]  A. C. Q. Ladeira, V. S. T. Ciminelli, Adsorption and desorption of arsenic on an oxisol and its constituents. Water Res. 2004, 38, 2087.
Adsorption and desorption of arsenic on an oxisol and its constituents.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2cXjtFCktb8%3D&md5=cb6421b63b030621154419d4839e002dCAS |