蒙脱土对聚羧酸超塑化剂的吸附行为

Adsorption Behavior of Polycarboxylate Superplasticizers onto Montmorillonite

摘要:

测定了蒙脱土对聚羧酸超塑化剂(PCE)分散性能的影响，研究了蒸馏水和水泥滤液中蒙脱土对PCE的静态吸附和动态吸附行为，拟合了吸附过程的动力学模型.结果表明：水泥中掺入蒙脱土会导致PCE对水泥分散能力的显著降低；蒙脱土对PCE的吸附量与PCE质量浓度近似成正比关系；水泥滤液中，PCE在蒙脱土上的平衡吸附量要远高于蒸馏水中的平衡吸附量；PCE在蒙脱土上的吸附过程均符合准二级反应动力学模型.

Abstract:

The effect of montmorillonite(MMT) on the dispersion properties of polycarboxylate superplasticizers(PCE) was investigated. The static and dynamic adsorption behaviors of PCE onto MMT in distilled water and cement filtrate were studied respectively. The results show that adding the MMT into cement could significantly decrease the dispersion properties of PCE. The amount of PCE adsorbed onto MMT is roughly directly proportional to the mass concentrations of PCE. The saturation amount of PCE adsorbed onto MMT in cement filtrate is much higher than that in distilled water, and the adsorption process could be well described using pseudo second order reaction kinetics model.