Study on Sparingly-Soluble Carbonete Crystallization as Technology for CO_2 Fixation

采用间歇式反应结晶实验，考察了L-天冬氨酸和L-甘氨酸对结晶速率的影响。结果表明，与结晶操作因素的影响相比，它们的影响并不显著。然后对反应结晶进行了研究，得到了过饱和度、生成速率、温度和混合对碳酸钙晶体形状的影响。在上述研究结果的基础上，将钙盐和碳酸盐溶液直接混合应用于碳酸钙常温常压结晶，认识到固体氯化钠的加入能有效地选择性地形成钙，而球铁矿在没有添加的情况下结晶较多。加料方式、反应物浓度对晶体形状和尺寸分布也有影响。从而发现了不陈化的微粉通过氯化钠表面的溶解选择性地转化为方解石的新现象，并获得了方解石的生长速率。本研究可定位为微生物研究，不仅有助于碳酸钙结晶二氧化碳浮选新工艺的开发，

Reactive crystallization tests were done batch-wisely, to examine the effect of l-aspartic acid and l-glycine on the crystallization rate. From the results, effect of them was recognized not to be significant in comparison to the effect of crystallization operation factors. Then studies on reactive crystallization were carried out to obtain the effect of supersaturation, the rate of its formation, temperature and mixing on the shape of calcium carbonate crystals. Based on the results of above studies, direct mixing of calcium salt and carbonate sollution was applied to calcium carbonate crystallization under normal temperature and pressure, to recognize that solid sodium chloride addition was effective to form calciteselectively, althogh vaterite crystallized much without its addition. And also method of addition, reactant concentration affected crystal shape and size distribution. Consequently new phenomena that unstale microfines were transformed selectively to calcite by dissolution of sodium chloride surface, was found, and growth rate of calcite was obtained. This study could be located as a germic reserach, and it will contribute not only to the new process development of carbon dioxide flxation by calcium carbonate crystallization,