| 摘要 |
PURPOSE: Chitosan is provided for use as a coating agent increasing slow releasing property of chemical fertilizer. Therefore, the chitosan-coated fertilizer improves soil, and increases the growth of root and sterilization, thereby decreasing the overuse of fertilizer. CONSTITUTION: The coating agent of slow release chemical fertilizer is produced by the following steps of: mixing insoluble chitosan, having more than 90% of deacetylation degree, up to 12% of moisture content and 300-1000cps of viscosity, with HCl(>=35%) and water in a ratio of 1:4, and dehydrating; mixing with alcohol(>=80%) and water in a ratio of 1:5, and dehydrating; drying at 170-250deg.C and grinding to a 80mesh size. The chitosan coating agent is produced by mixing chitosan, distilled water and soluble trace elements(Mg, Mn, Zn and B) in a ratio of 3-7 : 87.5-96.5 : 0.5-5.5. The prepared chitosan is mixed with fertilizer materials in a ratio of 2-6 : 1000 for coating. |
