摘要
表面活性剂因大量被使用,成为环境水体中普遍存在的物质.其具有包裹难溶性物质而形成胶体的特点,是难溶且具有环境风险的有机物在水体中存在和转移的载体.为了对其处理过程中的行为加以控制,以阴离子表面活性剂SDBS胶束溶液为模型化合物,研究了其在不同铝盐剂量下的凝聚特征现象,针对不同pH条件下的特征比较,结合Zeta电位和表面张力分析了其作用过程及铝盐和SDBS的计量关系.结果表明,①pH在4左右时凝聚计量摩尔比CAl:CSDBS约为0.4,在pH为5～9范围内约为0.15.②pH在5～6范围内,体系Zeta平衡值接近零点,表面张力峰值较大.③Al与SDBS摩尔比增加接近3时,体系凝聚体逐渐减少.据此认为,在最佳的絮凝状态下,表面活性剂与化学凝聚药物之间存在化学计量关系.
Suffactant is a ubiquitous substance in aquatic environment owing to its popular usage. Because of the characteristics of enwrapping insoluble substances and forming colloids, it becomes the carrier of insoluble environmental hazardous substances to water body. To control its behaviors in disposal processes, the coagulation characteristics of anionic surfactant sodium dodecyl benzene sulphonate （SDBS） micellar solution with different dosage of AI salt were investigated. Based on several phenomena observed in samples with different pH, combined with the change of Zeta potential and surface tension measurements, the possible mechanism in each case was investigated. With the experimental evidences, the preferable stoichiometric proportion of A1 and SDBS was discussed. Results show that, ① The preferable molar ratio of A1 to SDBS is about 1 ： 3 in samples around pH 4, and about 1 ： 7 in those of pH within 5-9. ② Under the weak-acidic pH condition about 5-6, the equilibrium zeta potential is near zero and the peak value of surface tension is high. ③ When the molar ratio of AI to SDBS is raised to around 3, the coagulation reduce gradually. It can be thought that the stoichiometric relationship maybe exist between surfactant and coagulant to obtain the rational effect.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2009年第1期151-154,共4页
Environmental Science
基金
国家自然科学基金项目(20577005)
