| Title | Adsorption and desorption of phenylarsonic acid compounds on metal oxide and hydroxide, and clay minerals |
| Authors | Xie, Xiande Cheng, Hefa |
| Affiliation | Peking Univ, Coll Urban & Environm Sci, MOE Lab Earth Surface Proc, Beijing 100871, Peoples R China Hunan Agr Univ, Coll Resources & Environm, Changsha 410128, Peoples R China |
| Keywords | P-ARSANILIC ACID ATR-FTIR POULTRY LITTER IRON (OXYHYDR)OXIDES ORGANOARSENIC COMPOUNDS COMPETITIVE ADSORPTION SURFACE COMPLEXATION ENVIRONMENTAL FATE SORPTION ROXARSONE |
| Issue Date | 25-Feb-2021 |
| Publisher | SCIENCE OF THE TOTAL ENVIRONMENT |
| Abstract | Adsorption and desorption of p-arsanilic add (p-ASA) and rexarsone (ROX) on six soil minerals, including hematite (alpha-Fe2O3), goethite (alpha-FeOOH), ferrihydrite (Fe(OH)(3)), aluminum oxide (alpha-Al2O3), manganese oxide (gamma-MnO2), and kaolinite, were studied, and the impact of solution matrices on their adsorption was systematically evaluated. Adsorption of p-ASA/ROX on the metal (hydro)oxide and clay minerals occurred quickly (mostly within 2 h), and could be well described by the pseudo second-order kinetic model. The apparent maximum adsorption capacities of alpha-Fe2O3, alpha-FeOOH, Fe(OH)(3), alpha-Al2O3, gamma-MnO2, and kaolinite (at an initial pH of 7.0) for p-ASA were 1.7, 0.9. 2.5, 0.08, 1.1, and 0.02 mu mol/m(2), while those for ROX were 1.6, 0.7. 2.4. 0.1. 0.5. and 0.05 mu mol/m(2). respectively. Besides adsorbing p-ASA/ROX, gamma-MnO2 also caused their oxidation. Experimental results suggest that formation of inner-sphere complexes through the arsonic acid group is the primary mechanism for adsorption of p-ASA/ROX on iron (hydro)oxides and -gamma-MnO2, while outer-sphere complexation plays a critical role in their adsorption on alpha-Al2O3 and kaolinite. Adsorption of p-ASA/ROX on the metal (hydro)oxide and clay minerals was affected by solution pH, co-existing metal ions (Ca2+, Mg2+, Al3+, Cu2+, Fe3+, and Zn2+). oxyanions (H2PO4-, HCO3-, and SO42-), and humic acid. The solid-to-liquid partition coefficients of p-ASA during the desorption from alpha-Fe2O3, alpha-FeOOH, Fe(OH)(3), alpha-Al2O3, gamma-MnO2, and kaolinite were 0.47, 2.69,4.38, 0.03, 30.4, and 0.1 L/g, while those of ROX were 028, 1.68, 3.48, 0.02, 4.0, and 0.02 L/g, respectively. Agricultural soils with lower contents of organic carbon exhibited higher adsorption capacities towards p-ASA/ROX, which indicates that soil minerals play a key role in the adsorption of phenylarsonic acid compounds while organic matter could have strong inhibitory effect. These findings could help better understand and predict the transport and fate of p-ASA/ROX in surface soils with low contents of organic matter. (C) 2020 Elsevier B.V. All rights reserved. |
| URI | http://hdl.handle.net/20.500.11897/603127 |
| ISSN | 0048-9697 |
| DOI | 10.1016/j.scitotenv.2020.143765 |
| Indexed | EI SCI(E) |
| Appears in Collections: | 城市与环境学院 地表过程分析与模拟教育部重点实验室 |
