【摘 要】
：
The adsorption and desorption characteristics of Al3+ to/from humic acids at different pH, ionic strength, and temperature were studied by the C-25 glucosan-gel
【机 构】
：
College of Resources and Environment,Chongqing Key Laboratory of Agricultural Resources and Environm
【基金项目】
：
the Post doctoral Foundation of Southwest University of China;国家自然科学基金
论文部分内容阅读
The adsorption and desorption characteristics of Al3+ to/from humic acids at different pH, ionic strength, and temperature were studied by the C-25 glucosan-gel chromatography method. The results showed that the maximum adsorption amount (Qmax) and adsorption constant (k) increased, whereas, the absolute value of standard thermodynamic molar free energy change (AG0. m) decreased with the increase of pH at constant ionic strength and temperature. With ionic strength increasing from 0 to 0. 15 mol/L, Qmax and k increased and the absolute value of AG0. m decreased at constant pH and temperature. High temperature was unfavorable for the adsorption reaction, as indicated by the dramatic decrease of Qmax and the absolute value of AG0. m with an increase in temperature. The standard thermodynamic molar free energy change (AG0. m) and the standard thermodynamic enthalpy change (AH0. m) of the adsorption reaction were both negative, suggesting that adsorption reaction was spontaneous and exothermic. The desorption rate of HA-AI3+ complex accelerated with the decrease of pH, and a significant linear relationship could be obtained between pH and the desorption rates of Al3+ from humic acids. These results demonstrated that the Al3+ adsorption reaction was a "biphase" reaction, and adsorption occurred at both the interior and exterior adsorption sites of humic acids.
其他文献
A bacterial strain,designated as LS,was isolated from a contaminated soil and was found to be capable of utilizing quinelorac,bensulfuromnethyl,and a mixture of
This study tested and evaluated the agricultural non-point source(AGNPS)model for the Wuchuan catchment, a typical agricultural area in the Jiulong River waters
The excellent response characteristics and detection sensitivity with much lower operational cost and the capability to discriminate between the isomer of some
Reactions of NiCl2·6H2O with dmpzm and formic or acetic acid at PH = 7 pro- duced the two title compounds, [Ni(dmpzm)2(HCO2)]Cl·2H2O 1 and [Ni(dmpzm)2(Oac)]Cl
Based on the successful performance of a lab-scale upflow anaerobic sludge blanket (UASB) reactor with the capacity of simultaneous methanogenesis and denitrifi
Membrane fouling is one of the most important challenges faced in membrane ultrafiltration operations. The copolymers of polysulfone-graft-methyl acrylate were
Black soil (Mollisol) is one of the main soil types in northeastern China.Biolog and polymerase chain reactiondenaturing gradient gel electrophoresis (PCR-DGGE)
Organic matter is known to be the precursor of numerous chlorination by-products. Organic matter in the secondary effluent from the Wenchang Wastewater Treatmen
Biolog,16S rRNA gene denaturing gradient gel electrophoresis (DGGE),and phospholipid fatty acid (PLFA) analyses were used to assess soil microbial community cha
Experiments were carried out to characterize the transformation of lipids in activated sludge under aerobic conditions. Results showed that the overall lipid co