葡萄糖酸钙结晶的热力学特性  

Thermodynamic properties of calcium gluconate crystallization

作　　者：梁玺 赵改菊 路春美[1] 牛胜利[1] LIANG Xi;ZHAO Gai-ju;LU Chun-mei;NIU Sheng-li(School of Energy and Power Engineering,Shandong University,Jinan 250061,Shandong Province,China;Energy Research Institute,Qilu University of Technology(Shandong Academy of Sciences),Jinan 250014,Shandong Province,China)

机构地区：[1]山东大学能源与动力工程学院,山东济南250061 [2]齐鲁工业大学(山东省科学院)能源研究所,山东济南250014

出　　处：《化学工程》2021年第3期22-27,共6页Chemical Engineering(China)

基　　金：齐鲁工业大学(山东省科学院)院地产学研协同创新基金项目资助(2017CXY-12)。

摘　　要：采用EDTA配位滴定法测定了葡萄糖酸钙在水中293.15—333.15 K的溶解度数据并绘制溶解度曲线,同时采用溶解度模型——λh方程和Apelblat方程对溶解度数据进行了关联。结果表明随着温度升高葡萄糖酸钙在水中的溶解度增大,两方程对于溶解度的关联性相比,Apelblat方程对溶解度的关联效果更好。采用电导率法测定了超溶解度曲线并用Apelblat方程进行关联,确定了葡萄糖酸钙溶液的介稳区随温度的变化规律,并考察了不同搅拌速率、降温速率和pH值对介稳区宽度的影响。结果表明葡萄糖酸钙的介稳区在低温区较宽,高温区较窄,搅拌速率的降低和降温速率的增加会使葡萄糖酸钙介稳区变宽,pH值对葡萄糖酸钙介稳区的宽度没有明显影响,这为葡萄糖酸钙工业结晶装置及工业结晶生产操作提供了理论依据。The solubility data of calcium gluconate in water at 293.15-333.15 K was measured by EDTA coordination titration and the solubility curve was drawn.At the same time,the solubility model—λh equation and Apelblat equation were used to correlate the solubility data.The results show that the solubility of calcium gluconate in water increases with temperature increasing.Compared with the correlation between the two equations for solubilty,Apelblat equation has a better correlation for solubility.The super-solubility was measured by the conductivity method and correlated with Apelblat equation to determine the change rule of the metastable zone of calcium gluconate solution with temperature.The effects of different stirring rates,cooling rates and pH on the width of the metastable zone were also investigated.The results show that the metastable zone of calcium gluconate is wider in the low temperature and narrower in the high temperature.The decrease of the stirring rate and the increase of the cooling rate will widen the calcium gluconate metastable zone,and pH has no significant effect on the width of the calcium gluconate metastable zone.It provides a theoretical basis for calcium gluconate industrial crystallization equipment and the operations of industrial crystallization production.

关 键 词：葡萄糖酸钙 结晶 溶解度 介稳区 

分 类 号：O795[理学—晶体学]