Dissolution Modeling and Experimental Measurement of CaS-H20 Binary System  

作　　者：Zekker, Ivar Tenno, Toomas Selberg, Aare Uiga, Katev 

机构地区：[1]Institute of Chemistry, University of Tartu, 14A Ravila St., Tartu, 50411, Estonia

出　　处：《Chinese Journal of Chemistry》2011年第11期2327-2336,共10页中国化学（英文版）

摘　　要：CaS formed during the retorting process of oil shale has a hazardous influence on surface water quality. Interaction of retorted oil shale with water generates highly alkaline leachate with a high content of sulfur due to the CaS component. A theoretical model describing the behavior of solid calcium sulfide in contact with water was developed. The model was consistent with the measurements showing change in dissolution behavior when solid CaS remained in the solution. Experimental measurements of pH and concentrations of ions were carried out in oxy- gen-free water at 25 ~C using CaS concentrations from 24.2-131.5 mgoL-1 （0.335--1.823 mmol/L）. Analysis of pH and concentrations of ions in the solution and calculations by the developed model showed that the solubility of CaS was estimated as 125.0 mg·L 1 （1.733 mmol/L）, and therefore the solubility product of CaS is 3.41×10^-10 （mo·L^-1）^2 at a temperature of 25℃.CaS formed during the retorting process of oil shale has a hazardous influence on surface water quality. Interaction of retorted oil shale with water generates highly alkaline leachate with a high content of sulfur due to the CaS component. A theoretical model describing the behavior of solid calcium sulfide in contact with water was developed. The model was consistent with the measurements showing change in dissolution behavior when solid CaS remained in the solution. Experimental measurements of pH and concentrations of ions were carried out in oxy- gen-free water at 25 ~C using CaS concentrations from 24.2-131.5 mgoL-1 （0.335--1.823 mmol/L）. Analysis of pH and concentrations of ions in the solution and calculations by the developed model showed that the solubility of CaS was estimated as 125.0 mg·L 1 （1.733 mmol/L）, and therefore the solubility product of CaS is 3.41×10^-10 （mo·L^-1）^2 at a temperature of 25℃.

关 键 词：calcium sulfide （CaS） solubility product the dissociation constants of H2S chemical equilibrium 

分 类 号：X824[环境科学与工程—环境工程] TG142.31[一般工业技术—材料科学与工程]