磷酸二铵中有效五氧化二磷的测定

Determination of Available P_2O_5 in DAP

按GB/T 10 2 0 9.2 - 2 0 0 1规定 ,磷酸二铵 (DAP)中有效五氧化二磷的整个测定过程需时约 3h。笔者在实际操作中 ,称取 0 .5gDAP分析试样 ,加入 80mL事先预热至 (80± 2 )℃的 0 .1mol/L的EDTA提取 15min ,整个有效磷的测定过程需时约 2h。该方法的分析时间比国标方法缩短了 1/ 3,且有良好的精密度及准确度 ,具有实用性。

As specified in the standard GB/T 10209.2 2001,the whole process of determination of available P 2O 5 in diammonium phosphate(DAP) requires about 3 hours. The writers in their actual operation weigh out 0.5 g of DAP as the analytical sample, and add 80 mL of 0.1 mol/L EDTA preheated to (80±2)℃ to extract for 15 min; the whole process of available P 2O 5 determination lasts for nearly 2 hours. This method shortens the analytical period for the international method by 1/3, shows good precision and accuracy and is thus practical.