潲水油醇解制备固液反应型包膜控释肥膜材的方法及膜控释性能

Preparation and Releasing Capability of Solid-Liquid Reaction Coated Controlled-Release Fertilizers Films from Hogwash Oil

探讨以潲水油为主要原料制备包膜缓/控释肥膜材的工艺方法,并采用固液反应包膜工艺制备了6种包膜尿素,通过水浸泡法对包膜尿素的氮素控释性能进行了研究。结果表明：潲水油精制以添加浓硫酸2.6%、水40%和6次水洗可获得较高的回收率,比采用磷酸精制经济;醇解工艺中潲水油与多羟基化合物物质的量比为1.0∶0.7-1.0∶0.9时可获得适宜粘度和羟值的醇解产物;醇解潲水油与多聚异氰酸酯不同配比的膜材预聚体与膨润土制得的膜对尿素饱和溶液中尿素透过量测定结果显示,膜的通透性随膜材预聚体中醇解潲水油比例的增加而增大;分别采用2种不同羟值醇解潲水油与多聚异氰酸酯按质量比2.0∶1.0、2.5∶1.0和3.0∶1.0配制膜材预聚体制备的6种包膜尿素水中溶出率试验结果表明,6种包膜尿素均具有良好的控释效果,养分水中24 h溶出率为8.9%-11.1%,7 d累计溶出率为35.7%-42.1%。

The preparation techniques of slow/controlled-release fertilizers films with hogwash oil as the starting material was studied.Six coated urea were prepared through solid-liquid reaction,and their controlled-release capability of nitrogen was researched with water dissolution.Results showed that the maximum recovery rate of hogwash oil can be obtained by addition of sulphuric acid 2.6%,water 40%,and then water washing six times.Sulphuric acid is more economic than phosphate acid.Alcoholysis hogwash oil with suitable viscosity and hydroxyl value can be got when hogwash oil reacts with polyisocyanate（mole ratio（1.0∶0.7）-（1.0∶0.9））;The characteristic films made from prepolymer of alcoholysis hogwash oil and polyisocyanate with bentonite were determined by nitrogen transiting dose of the saturated urea solution,and the membrane permeability was increased along with the proportion of alcoholysis hogwash oil.Six coated urea with well controlled-release effect for water dissolution rate could be produced along with two kind hydroxyl value alcoholysis hogwash oil and two ratio of hogwash oil to polyisocyanate（mass ratio：2.5∶1.0 and 3.0∶1.0）,the dissolution rate in water is 8.9%-11.1% in 24 h,seven days cumulate ones is 35.7%-42.1%.