尿素中亚甲基二脲含量测定——萘二磺酸二钠盐分光光度法的研究和应用

Determination of Methylene Diurea in Urea: Study and Use of Disodium Naphthalene Disulfonate Spectrophotometry

尿素溶液中加入甲醛 ,可用于大颗粒尿素的生产 ,同时可提高成品颗粒强度 ,降低粉尘 ,这是目前尿素企业生产控制的一种措施 ,甲醛在尿素成品中转化为亚甲基二脲。本文研究了用萘二磺酸二钠盐分光光度法测定尿素中亚甲基二脲含量的测试条件 ,并通过精密度、回收率以及对检测样品的各实验室比对试验 ,表明了该方法是准确、可行的。本方法已作为新的方法标准列入尿素国家标准之中。

Urea solution with the addition of formaldehyde can be used to produce larger urea prills, the strength of the product prills is improved, and dust is reduced; such is a measure currently used in urea plants for production control. Formaldehyde in the urea product trans forms into methylene diurea. The authors have studied the testing conditions for the determination of methylene diurea in urea by disodium naphthalene disulfonate (color changing acid) spectrophotometry, and they have shown that the method is accurate and feasible after studying the precision and recovery and the comparative tests on the samples determined in various laboratories. The method has been listed in the state standard for urea as a new one.