Establishing models for wet process phosphoric acid purification with methyl isobutyl ketone

The present paper reports results for the purification of phosphoric acid b y liquid-liquid extraction with methylisobutylketone. The simultaneous effe ct of some operating parameters, namely concentration of the feed acid, mas sic ratio of solvent to feed, temperature and number of theoretical stages, on the performances of the extraction step has been examined using a facto rial design 2(4). The established models allowed us to forecast the experim ental conditions required to obtain a given yield of P2O5 and/or a well-def ined quality of the stripped acid. The optimal conditions have been determi ned by using a desirability function.