关键词: 高强石膏前驱体;α型半水硫酸钙;合成反应

Abstract: 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 CaCl2 and Na2SO4) 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).

Key words: high-strength gypsum precursors;alpha calcium sulfate hemihydrate;synthesis reaction