论文部分内容阅读
对碳酸氢铵沉淀钇时碳酸钇铵复盐结晶的形成条件与pH变化特征进行了研究 ,发现其结晶过程与平衡溶液pH有对应关系。溶液pH由碳酸钇铵结晶化反应和碳酸氢铵的水解反应所控制。根据溶液pH的变化可以判断结晶反应是否发生或完成 ,以及结晶速度的快慢和结晶的程度。X -射线衍射及差热 -热重分析结果表明 ,产物为复盐结晶 ,加料比与加料方式对结晶的形成有很大影响。
The formation conditions of yttrium ammonium carbonate bicarbonate and its pH variation were studied when ammonium bicarbonate precipitated yttrium. It was found that the crystallization process is related to the pH of equilibrium solution. The pH of the solution is controlled by the crystallization reaction of yttrium carbonate carbonate and the hydrolysis reaction of ammonium bicarbonate. According to the change of the pH of the solution, it can be judged whether the crystallization reaction takes place or is completed, and the speed of crystallization and the degree of crystallization. The results of XRD and DTA - TGA showed that the product was double salt crystallization. The addition ratio and feeding mode had great influence on the formation of crystal.