摘要
采用紫外吸收光谱分析仪、微电泳仪、X光电子能谱分析技术研究了FDN在α半水脱硫石膏表面的吸附特性、表面电化学性质及其对流动性的影响。结果表明:α半水脱硫石膏对FDN吸附为化学吸附,吸附等温线基本符合Langmuir方程,吸附热为5.76kJ/mol,吸附层厚度为9nm;FDN为平躺吸附,吸附层空间位阻小,其分散作用主要依赖ξ电位的静电斥力,而ξ电位取决于FDN首层吸附量;α半水脱硫石膏水化很快,其水化产物覆盖对静电斥力有屏蔽效应,静电斥力分散作用的稳定性差,流动度经时损失较大。
By using UV adsorption spectrophotometer, micro-electrophoresis, and X-ray photo spectroscopy technology, the adsorption characteristics, surface electrochemical properties of FDN on α-hemihydrate desulfogypsum and their effects on fluidity of gypsum piaster were researched. The results show that the adsorption of FDN on gypsum is physical adsorption. The adsorption isotherms curve basically obeys Langmuir equation, its adsorption heat is 5.76 kJ/mol and thickness of adsorption layer is 9 nm. The adsorption conformation of FDN is in form of lying on gypsum surface and the steric hindrance is very weak, its dispersion depending mainly on electrostatic repulsive force caused by Zeta potential which depends on adsorption amount on the surface of gypsum particle. The stability of electrostatic repulsive force effect is weak because of the shelter effect of new hydration products, leading to rapid fluidity loss of fresh gypsum piaster.
出处
《武汉理工大学学报》
CAS
CSCD
北大核心
2011年第10期12-15,共4页
Journal of Wuhan University of Technology
基金
国家自然科学基金(50872160)
关键词
α半水脱硫石膏
减水剂
吸附
分散性
α-hemihydrate desulfogypsum
water reducer
adsorption
dispersion
