Aluminum organic coprecipitates play important roles in the transport of oxyanions in soil environment.A new polynuclear aluminum organomineral precipitate(Al13-oxalate precipitate) was prepared to investigate the ads...Aluminum organic coprecipitates play important roles in the transport of oxyanions in soil environment.A new polynuclear aluminum organomineral precipitate(Al13-oxalate precipitate) was prepared to investigate the adsorption behavior of arsenate and phosphate on noncrystalline aluminum precipitates.Important thermodynamic parameters for adsorption reaction were evaluated using macroscopic adsorption data and equations.The result showed that,the adsorption reaction basically is a diffusion process.FTIR spectroscopic studies have provided evidence for the formation of two different types of complexes in substrate,protonated bidentate and deprotonated bidentate complexes at pH 4 and pH≥6,respectively.The classic competitive adsorption and XPS studies both indicated that phosphate has stronger chemical interaction with substrate than arsenate.The findings of XPS studies revealed that the precipitate substrate can act as Lewis acid when adsorbing oxyanions.展开更多
基金funded jointly by the National Natural Science Foundation of China (Grant No. 41002128)the Open Research Project of State Key Laboratory of Coal Resource & Mining Safety (SKLCRSM09KFB05)Doctorial Research Fund of Southwest University of Science and Technology (09ZX7115)
文摘Aluminum organic coprecipitates play important roles in the transport of oxyanions in soil environment.A new polynuclear aluminum organomineral precipitate(Al13-oxalate precipitate) was prepared to investigate the adsorption behavior of arsenate and phosphate on noncrystalline aluminum precipitates.Important thermodynamic parameters for adsorption reaction were evaluated using macroscopic adsorption data and equations.The result showed that,the adsorption reaction basically is a diffusion process.FTIR spectroscopic studies have provided evidence for the formation of two different types of complexes in substrate,protonated bidentate and deprotonated bidentate complexes at pH 4 and pH≥6,respectively.The classic competitive adsorption and XPS studies both indicated that phosphate has stronger chemical interaction with substrate than arsenate.The findings of XPS studies revealed that the precipitate substrate can act as Lewis acid when adsorbing oxyanions.
