缩二脲试液浑浊的处理  

TREATMENT OF TURBID BIURET TEST SOLUTION

作　　者：陈录华 胡威盛 

机构地区：[1]中海石油化学股份有限公司,海南东方572600

出　　处：《大氮肥》2008年第4期275-277,共3页Large Scale Nitrogenous Fertilizer Industry

摘　　要：尿素生产过程中因添加甲醛而产生脲甲醛聚合物,影响缩二脲的分析检验。采用加盐酸加热的处理方法,将脲甲醛聚合物分解,使浑浊的试液变得清澈透亮,保证分析结果准确可靠。In urea production, the addition of formaldehyde produces ureaform polymer. In analysis and testing of biuret, there is turbid or visible floccule in the testing solution, resulting in false high reading of biuret. When hydrochloric acid was added and heated, ureaform polymer was cracked, the turbid solution became clear and transparent, then NaOH solution was added to adjust the solution from acid （pH 〈 3） into weak alkaline （pH7.5 - 8）, and then measure the biuret content by colorimetry, a true reading can be obtained. If no NaOH solution is added to adjust pH value, the color development by adding copper salt will be interfered, leading to false low reading. This method is safe and easy, no more special chemical reagent or special test instrument is needed.

关 键 词：缩二脲 脲甲醛 加酸加热 

分 类 号：TQ441.41[化学工程—化学肥料工业] TS262.3[轻工技术与工程—发酵工程]