pH值对脲甲醛溶解性的影响程度分析

Effect of pH Value on Solubility of Urea Formaldehyde

尿素/甲醛反应合成脲甲醛,脲甲醛聚合程度决定脲甲醛的溶解性,溶解性决定肥效期。脲甲醛的溶解性与尿素/甲醛(U/F)摩尔比、反应温度、反应时间、pH值、加料方式等有直接关系。本文主要研究尿素/甲醛反应聚合时pH值因素变化对脲甲醛缓释肥冷水不溶性氮、热水不溶性氮、缓释有效氮的影响,筛选尿素/甲醛反应合成脲甲醛适宜pH值。

The urea / formaldehyde reaction for the synthesis of urea formaldehyde, urea formaldehyde polymerization degree determines the solubility of urea formaldehyde, dissolved fertilizer period decision. The solubility of urea formaldehyde and urea / formaldehyde （U/F） mole ratio, reaction temperature, reaction time, pH value, feeding method and so on have direct relations. This paper mainly studies the urea formaldehyde polymerization when pH value influence factors of urea formaldehyde slow - release fertilizer water insoluble nitrogen and water insoluble nitrogen, effective nitrogen release, screening of urea / formaldehyde reaction synthesis of urea formaldehyde suitable pH value.