铬盐清洁工艺亚熔盐介质脱除铝酸钾、碳酸钾研究 Ⅱ.结晶工艺  

Removal of potassium aluminate and potassium carbonate from sub-molten media in a new cleaner production technology of chromate Ⅱ.Crystallization Process

作　　者：杜春华[1,2] 

机构地区：[1]青岛农业大学山东省农业仿生应用工程技术研究中心,山东青岛266109 [2]中国科学院过程工程研究所,北京100080

出　　处：《化工科技》2008年第5期1-4,共4页Science & Technology in Chemical Industry

基　　金：国家自然科学重点基金资助项目(50234040);中科院知识创新重大项目(KCCX1-SW-22);国家863计划资助项目(2005AA647010)。

摘　　要：针对铬盐清洁工艺亚熔盐介质净化过程,研究了KOH-K_2CO_3-Al_2O_3-SiO_2-H_2O体系铝酸钾、碳酸钾混合盐的结晶行为。发现冷却时间、搅拌速率、冷却方式对结晶平均粒径具有重要影响,对晶种浓度也有一定影响。与控制冷却相比,线性冷却方式产生的结晶粒径稍小,除杂效果较好。在最佳工艺条件下亚熔盐介质中碳酸钾、铝酸钾的质量分数可分别降至4.67%、0.98%(以Al计),实现了亚熔盐介质的有效净化。To purify the the sub-molten salt media in the new cleaner production technology of chro- mate,the crystallization behavior of potassium aluminate hydrated and potassium carbonate hydrated from the KOH-KAlO2-K2 CO3-K2 SiO3-H2O system investigated. The results confirmed the prevailing importance of the cooling time,agitation rate and the cooling mode. The mass of seed crystals also has some influence on the mean crystals size. The linear mode leads to slightly lower mean crystals size and results in lower concentrations of soluble alumina and potassium carbonate in mother liquor, compared with controlled cooling mode. It was found that, under the optimal operation conditions, the concentrations of potassium carbonate and potassium aluminate can be decreased to as low as 4.67% and 0.98o//00 （counted by Al）, respectively, and therefore the effective purification of sub-molten salt media is achieved before it＇s recycled.

关 键 词：铬盐清洁生产 亚熔盐介质 冷却结晶 线性冷却 

分 类 号：TQ136.11[化学工程—无机化工]