PREPARATION OF MONOCALCIUM PHOSPHATE FROM HYDRATED LIME

Abstract

This study was carried out with laboratory experiments to prepare of mono calcium phosphate (mono hydrate) CaH4(PO4)2.H2O from hydrated lime which is produced in the Southern Cement State (pasty) apparatus with hydrated lime (solid powder) in 1/5 ratio, CaO/P2O5 at (room Company \ Alnoora factory, Karbala Governorate and phosphoric acid (analytical grade) because the impurities in technical grade is not acceptable in food grade. These experiments include exothermic reaction of 85% phosphoric acid concentration in a liquid –solid mixing temperature) as reaction temperature which was resulted in quick reaction (15 minute) between them and increased in temperature to the boiling point where water content was driven off as steam tend to speed up and carry to completion. The formation of the mono calcium phosphate which lead to permit the use of hydrated lime instead of calcium oxide or calcium carbonate. The produced CaH₄(PO₄).H₂Owas dried (aged) in an oven for (3-4) days at a temperature of about 48 ˚C. The product was formed in high purity 94.64% without any usually associated phosphoric compound in such reactionsand a (90.5)% particle size pass 150 micronwhich is critical for application as leavening agent.