Anti-solvent crystallization process of NH4VO3 in NaVO3-NH4Cl-H2O solution system
The anti-solvent crystallization technology of NH4VO3was proposed to deal with the problems of long induction period and low product yield in the process of NH4VO3 cooling crystallization.By using ethanol as anti-solvent and NH4Cl as precipitator,the effects of volume ratio of ethanol-leaching solution,NH4Cl initial concentration and temperature on the product yield were investigated by response surface methodology based on single factor experiment and the regression equa-tion for predicting the product yield was obtained.The results showed that the regression equation could predict the product yield well.There was only a significant interaction between the volume ratio of ethanol-leaching solution and the initial con-centration of NH4Cl.The influence of three factors on the product yield from high to low was volume ratio of ethanol-leaching solution,initial concentration of NH4Cl,temperature.The NH4VO3 products with yield greater than 95%were prepared un-der the conditions of crystallization time of 150 min,NH4Cl initial concentration of 0.68 mol/L,temperature of 278.15～288.15 K and volume ratio of ethanol-leaching solution of(1.5∶1)～(2∶1).The product morphology was flower-like structure with the size of 5～10 µm.
NETL
NSTL
万方数据
