Surface complexation model of boron adsorption by calcareous soils |
| |
Authors: | F Ranjbar M Jalali |
| |
Institution: | 1. Department of Soil Science, College of Agriculture, Bu-Ali Sina University, Hamedan, Iran
|
| |
Abstract: | This study aimed to evaluate boron (B) adsorption and the capacity of a surface complexation model for simulating this process in calcareous soils. Ten surface soils were collected from different land use areas in Hamedan, Western Iran, to characterize B sorption by soils. The mean B adsorbed by the sample soils varied from 8.9 to 32.8 %. Two empirical models including linear and Freundlich equations fitted well to the experimental data. The linear distribution (K d) values varied from 1.32 to 6.86 L kg?1, while the parameters of Freundlich equation including n and K Fr ranged from 1.16 to 1.33 and 3.31–16.81, respectively. The comparison of two empirical models indicated that B adsorption followed a nonlinear pattern. The soil organic matter had positive correlations with Freundlich and linear distribution coefficients. However, empirical models were not suitable for explaining the mechanism of B adsorption, so a surface complexation model was used to simulate and predict the B adsorption process. B adsorption modeling was conducted using Visual MINTEQ and PHREEQC, based on the assemblage of major surface components (hydrous ferric oxides, aluminum hydroxides, calcium carbonate, and humic acids). B adsorption was successfully modeled by surface complexation. The significant contribution of organic matter to B complexes was resulted from both experimental data and mechanistic modeling. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|