二氧化硅/聚乙二醇/VAE乳液复合包膜缓释肥的制备及性能

摘要

A coated slow - release fertilizer was prepared by using the by - product silica which is from the preparation of potassium fluoride with defluorization from wet process phosphoric acid,PEG,VAE emulsions,glycerin,aluminium phosphate mixed with water,then multiple sprayed the coated emulsions on DAP grain -fertilizer. The properties of slow -release with coating rate and the amount of silica added,and the properties of water retention in soil were studied.The results showed that the initial nutrient accumulative release rate of fertilizer was less than 15% and 28-day nutrient accumulative release rate was less than 80% which achieved the requirement of national standard of slow release fertilizer GB/T 23348 -2009;and the product could improve the largest water-holding ratio and water retention of soil,which could effectively improve the utilization of water resources.And the coating materials is biodegradable and it has no pollution.%以湿法磷酸脱氟制备氟化钾时的副产物二氧化硅,聚乙二醇,VAE乳液,丙三醇和磷酸铝为主要原料,以水为溶剂制成包膜乳液,采用多次雾化喷涂的方式对磷酸二铵颗粒肥料进行喷涂,制备了包膜缓释肥.研究了包覆率和二氧化硅加入量对其缓释性能的影响以及产品在土壤中的保水性能;并通过扫描电镜观察了包膜后肥料表面和剖面的形貌特征.结果表明:当包覆率达到40%时,产品的初期养分释放率小于15%,28天累积养分释放率小于80%,达到了缓释肥料国家标准GB/T 23348-2009的要求;产品在土壤中可以提高土壤的最大持水率和保水性能,对水资源利用率的提高具有重要意义,同时包膜材料还具有可生物降解、无环境污染等优点.