食品添加剂用超微二氧化钛改性研究

以六偏磷酸钠(NaPO3)6为表面活性剂,采用无机包覆方法进行表面改性以改善二氧化钛(TiO2)在水中的分散性,控制杂质含量使之符合食品添加剂的要求。对不同无机包覆剂(Al2O3,SiO2)进行对比研究通过改变TiO2与无机包覆剂的比例、反应pH、反应温度等条件研究了超微二氧化钛的分散性并将样品与食品添加剂杂质含量标准进行比较。结论如下,以(NaPO3)6作为表面活性剂,TiO2与SiO2的质量百分比为100∶1,pH为10,在80℃下反应时间1h,超微二氧化钛在水介质中的分散性及其稳定性良好,TiO2干基含量98.5%,Sb、Pb、Hg、Zn等杂质含量符合标准,是一种优良的高档食品添加剂。

This paper describes how to improve the dispersibility of super-fineTiO2 powder in water by using inorganic coating method with superficial active agents sodium hexametaphosphate. Impurity of sample was strictly controlled in order to achieve the requirement for food additive. In the experiments, the dispersibility of super-fineTiO2 powder in water has been studied by changing the mass percentage, reaction pH and reaction temperature of TiO2 coated SiO2, and TiO2 coated Al2O3. The conclusion is that using superficial active agents sodium hexametaphosphate, when the mass percentage of TiO2 and SiO2 is 100：1, pH value is 10,temperature is 80℃ and the reaction time is one hour, the stability and dispersibility of super-fine TiO2 in water are good and mass percentage of TiO2 of the sample is 98.5%, content of impurity lives up to the standard and it can be used as food additive.