title: Quantifying effects of pH and surface loading on arsenic adsorption on NanoActive alumina using a speciation-based model.
abstract: Arsenic (As) poses a significant water quality problem and challenge for the environmental engineers and scientists throughout the world. Batch tests were carried out in this study to investigate the adsorption of As(V) on NanoActive alumina. The arsenate adsorption envelopes on NanoActive alumina exhibited broad adsorption maxima when the initial As(V) loading was less than a 50 mg g(-1) sorbent. As the initial As(V) loading increased to 50 mg g(-1) sorbent, a distinct adsorption maximum was observed at pH 3.2-4.6. FTIR spectra revealed that only monodentate complexes were formed upon the adsorption of arsenate on NanoActive alumina over the entire pH range and arsenic loading conditions examined in this study. A speciation-based adsorption model was developed to describe arsenate adsorption on NanoActive alumina and it could simulate arsenate adsorption very well in a broad pH range of 1-10, and a wide arsenic loading range of 0.5-50 mg g(-1) adsorbent. Only four adjustable parameters, including three adsorption constants, were included in this model. This model offers a substantial improvement over existing models in accuracy and simplification in quantifying pH and surface loading effects on arsenic adsorption.
authors.affiliation: School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin, PR China.
authors.forename: Xiao-Hong
authors.initials: XH
authors.lastname: Guan
authors.forename: Tingzhi
authors.initials: T
authors.lastname: Su
authors.forename: Jianmin
authors.initials: J
authors.lastname: Wang
mesh_terms: D000327:Adsorption; D000537:Aluminum Oxide / Q000737:chemistry*; D001151:Arsenic / Q000302:isolation & purification*; D006256:Hazardous Waste / Q000517:prevention & control; D006863:Hydrogen-Ion Concentration; D008956:Models, Chemical; D017550:Spectroscopy, Fourier Transform Infrared; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*; D018508:Water Purification / Q000379:methods
chemical_list: D006256:Hazardous Waste; D014874:Water Pollutants, Chemical; D000537:Aluminum Oxide; D001151:Arsenic