以熔融石英为硅质原料动态水热合成硬硅钙石

Synthesis of xonotlite using fused silica as silica materials by dynamic hydrothermal process

采用熔融石英作为硅质原料,由碳酸钙煅烧获得的氧化钙作为钙质原料,在高压反应釜中动态水热合成硬硅钙石.研究了合成温度、保温时间、水固比对最终结晶产物的影响.采用XRD、SEM分析样品的物相和形貌.实验结果表明:合成硬硅钙石的最佳工艺条件为反应温度210℃、保温时间5.5h、水固比20;其制品体积密度为192kg/m3.使用熔融石英为原料,其反应活性高,用水量降低,与普通石英原料相比水固比下降50%,大幅提高了生产效率.

Xonotlite was synthesized using fused silica and calcium oxide obtained by calcining cal‐cium carbonate by dynamic hydrothermal process in the sealed steel alloy autoclaves in this paper . The effects of the reaction temperature ,holding time ,water-solid ratio on the final crystalline product were studied .The phase composition of the samples was examined by XRD .The micro‐structure was observed with SEM .The optimum conditions of synthesizing xonotlite were the re‐action temperature w as 210℃ ,holding time w as 5 .5h ,and w ater-solid ratio w as 20 .T he parent density of crystalline product formed in die was 192kg/m3 .Water consumption decreased and wa‐ter-solid ratio dropped to 50% using fused silica as raw materials comparing to ordinary quartz due to its high reactivity .The production efficiency of xonotlite was improved evidently using fused silica as silica materials .