磷酸二氢钾结晶介稳区宽度的研究

Study on the crystallization metastable zone width of potassium dihydrogen phosphate

用激光散射法测定了磷酸二氢钾纯溶液和含有杂质或添加剂的磷酸二氢钾溶液在不同饱和温度下的结晶介稳区宽度,并用多元线性回归拟合得出磷酸二氢钾介稳区宽度与饱和温度及添加剂用量的回归方程,同时还考察了不同添加剂对结晶形状的影响。结果表明:磷酸二氢钾溶液的介稳区宽度随溶液饱和温度的升高而线性下降;添加剂硫酸钾和草酸钠用量的增加能使磷酸二氢钾溶液的介稳区宽度变窄;柠檬酸钠则能使磷酸二氢钾溶液的介稳区变宽。

The crystallization metastable zone widths （ MZW ） of pure potassium dihydrogen phosphate （ KDP ） solution and impurities or additives bearing KDP solution were determined by laser light - scattering method at different saturation temperature. Based on multiple linear regression fitting, the regression equation expressing the influences of saturation temperature and the quantity of additives on the MZW of KDP was obtained. At the same time,the effects of different additives on crystal shape were examined. The results showed that MZW of KDP decreased linearly with the rise of saturation temperature of the solution. The MZW of KDP can be decreased by increasing the addition of potassium sulfate and sodium oxalate. Where as,the sodium citrate can enlarge the MZW of KDP.