Cu^(2+)与Zn^(2+)引发胡敏酸胶体凝聚比较研究  

A Comparative Study on Humic Acid Colloid Aggregation Induced by Specific Adsorption Ions Cu^(2+),Zn^(2+)

作　　者：傅强[1] 郭霞[1] 邵月[1] 朱华玲[1] 李航[1] 

机构地区：[1]西南大学资源环境学院,重庆400716

出　　处：《西南师范大学学报（自然科学版）》2013年第9期50-54,共5页Journal of Southwest China Normal University(Natural Science Edition)

基　　金：国家级大学生创新创业训练计划(201210635021);西南大学资源环境学院大学生科技创新"光炯"培育项目(20110106)

摘　　要：腐殖质是一类组成和结构都很复杂的天然高分子聚合物,胡敏酸是腐殖质的主要成分之一,系统地研究胡敏酸的结构特征对了解毒害有机污染物在环境中的迁移,转化过程具有重要意义.本文利用光散射技术比较研究了Cu2+和Zn2+吸附所引发的胡敏酸凝聚过程及凝聚体的结构特征.结果表明:①Cu2+和Zn2+作用下胡敏酸胶体凝聚特征类似,低浓度下胡敏酸凝聚体有效粒径随时间呈线性增长,高浓度下呈幂函数增长.②随着Cu2+和Zn2+浓度的增加,在同一体系下胡敏酸胶体颗粒的平均凝聚速率逐渐增加,形成的凝聚体分形维数逐渐降低,凝聚速率越快形成的凝聚体结构越疏松.③胡敏酸胶体的平均凝聚速率和凝聚体分形维数对Cu2+浓度的敏感性大于Zn2+.Interactions of humus particles induced by metal ions profoundly affect the formation of humus structure, and the migration and transportation of environmental contaminants. As humic acid is the main component of soil humus, aggregation kinetics of humic colloidal particles and structural and the resultant aggregates as affected by the different concentrations of CuC12, ZnC12 in the solutions have been studied comparatively by dynamic ／ static light scattering. Results indicate that the aggregation characters induced by two electrolytes are essentially similar. With the electrolyte concentration low, the effective diameter of humic aggregates in two electrolyte systems increases linearly, and then as a power function of time with the electrolyte concentration high. With rising the CuC12, ZnC12 concentration, the mean aggregation rates of humic colloids in the same electrolyte solution increased gradually and the fractal dimensions of the re sultant aggregates decreased, which implied that the faster aggregation velocity induced the more open or loose structure. The mean aggregating rates of humic particles and fractal dimensions of the resultant ag- gregates are more sensitive to CuC12 electrolyte concentration change than to ZnC12.

关 键 词：胡敏酸 光散射 凝聚 分形维数 

分 类 号：S153.3[农业科学—土壤学]