摘要
Hamaker常数是表征带电胶粒间范德华引力的关键参数,对于研究脱硫废水中氢氧化镁胶体的稳定性具有重要意义。本文以DLVO理论为基础,推导了球形氢氧化镁胶体在对称型电解质溶液中Hamaker常数的表达式。结果表明:氢氧化镁胶体的Hamaker常数与表面电位参数v_0、反离子价态z和临界聚沉浓度c_(ccc)有密切联系。采用动态光散射技术研究氢氧化镁胶体的凝聚过程,计算求得氯化钠溶液引起氢氧化镁胶体聚沉的临界聚沉浓度为47.28 mmol/L。结合Gouy-Chapman电位分布方程,推导了表面电位参数v_0的表达式,通过临界聚沉浓度下的_(ccc)电位求得氢氧化镁胶体的表面电位参数为0.357,同时计算出其在氯化钠溶液中的Hamaker常数为7.99×10^(-20) J。
The Hamaker constant is a key parameter for characterization of Van der Waals force between charged colloidal particles and is also of significance to studying the stability of magnesium hydroxide in desulfurization wastewater.In this study,the Hamaker constant of spherical magnesium hydroxide colloid in symmetric electrolyte solution was derived based on the DLVO theory.The results show that,the Hamaker constant is closely related to the surface potential parameter v0,antiionic valence z and critical coagulation concentration cccc of the spherical magnesium hydroxide colloid.The dynamic light scattering technology was applied to investigate the coagulation process of the magnesium hydroxide,and the critical coagulation concentration cccc of the sodium chloride solution was calculated as47.28mmol/L.Meanwhile,based on the Gouy-Chapman equation of potential distribution,expression of the surface potential parameter v0of the magnesium hydroxide was derived,and its calculated value was0.357.Furthermore,the Hamaker constant of the magnesium hydroxide in sodium chloride solution was calculated as7.99×10^-20J.
作者
张弦
叶春松
贾旭翔
刘通
黄建伟
ZHANG Xian;YE Chunsong;JIA Xuxiang;LIU Tong;HUANG Jianwei(School of Power and Mechanical Engineering, Wuhan University, Wuhan 430072, China)
出处
《热力发电》
CAS
北大核心
2018年第12期47-52,共6页
Thermal Power Generation
基金
国家自然科学基金项目(51602228)~~
关键词
氢氧化镁
胶体
DLVO
Hamaker常数
动态光散射
临界聚沉浓度
脱硫废水
magnesium hydroxide
colloid
DLVO
Hamaker constant
dynamic light scattering
criticalcoagulation concentration
desulfurization wastewater
