包覆型高铁酸钾缓释剂的制备及性能表征

Preparation and characterization of embedded potassium ferrate for controlled release

以切片石蜡为包覆壁材,以高铁酸钾为芯材,采用熔化悬浮冷凝法制得包覆型高铁酸钾。实验结果表明:分散方式对包覆率的影响很大,当搅拌速度为800r/min,超声时间为30min 时,包覆率可达到85.5%;采用红外光谱、X 射线衍射和扫描电镜对包覆后的产品进行了性能表征,结果发现,切片石蜡对高铁酸钾的包覆并没有破坏高铁酸钾的组分活性,包覆后高铁酸钾的缓释符合 Q=kt^n 动力学模型,而且持续缓释性能良好,切片石蜡与高铁酸钾质量比为3:1、5:1和10:1的包覆产品的理论缓释半衰期分别可达到7.5天、2.6月和17.0年。

Embedded potassium ferrate was prepared by the molten suspension and cooling （MSC） method with paraffin as embedded matrix and K2FeoO4 as embedded particles. The resuh shows that the encapsulation ratio can reach about 85.5% when stirring speed was at 800r/min and uhrasonic time was 30min. The characterization of embedded potassium ferrate by FTIR, XRD and SEM showed that the active component of K2FeO4 was not decomposed during the embedding process. The kinetics model of the release of K2FeO4 from the embedded particles was in good agreement with the equation Q=kt^n and the theoretical half-lives for releasing of the embedded K2FeO4 were 7.51 days, 2.61 months and 17.03 years respectively when the mass ratios of paraffin to potassium ferrate were 3：1,5：1 and 10：1.