反应物浓度与反应时间对高强石膏前驱体制备的影响

Influence of Reactant Concentration and Reaction Time on High-Strength Gypsum Precursors Synthesis

利用氨碱行业副产物氯化钙和硫酸钠为原料,合成高强石膏前驱体(二水硫酸钙),并通过常压水热法将二水硫酸钙转化为高强石膏(α型半水硫酸钙)。研究了反应物浓度和反应时间对于高强石膏前驱体合成的影响。结果表明:当反应物氯化钙和硫酸钠的浓度均小于或等于0.5 mol·L^(-1),反应时间为24 h左右时,制得的二水硫酸钙适用于常压水热反应,且其常压水热反应产物α型半水石膏晶体形貌良好,各项性能符合α30(JC/T 2038-2010)高强石膏标准。

High strength gypsum precursors（ Calcium Sulfate Dihydrate,CSD） was firstly prepared from calcium chloride（ byproduct from ammonia-alkali industry） and sodium sulfate,then alpha calcium sulfate hemihydrate（ α-CSH） was produced via non-autoclave hydrothermal reaction from CSD. The effects of reactant concentration and reaction time on CSD synthesis are investigated. Results indicate that,when reactants concentration（ both Ca Cl2 and Na2 SO4） are（ or below） 0. 5 mol·L^-1 and the reaction time is about 24 h,CSD could be produced and converted to well-developed α-CSH easily. The macro-performance of this kind α-CSH could meet the standard of α30（ JC/T 2038-2010）.