Physico-chemical investigation of AlPO4 for the manufacture of antacids. I. Effect of precipitation and processing conditions on physico-chemical properties of AlPO4.

Aluminium phosphate was precipitated from AlCl3-H3PO4 and NaOH, NH3H2O and NaHCO3--Na2CO3 mixture up to different pH values. The precipitates were dried at room temperature, 40 degrees and 105 degrees and their neutralizing properties (rate of neutralization and acid-consuming capacity) against 0.l N HCl were investigated. It was found that these properties depend on the nature of the reagents used for the formation of AlPO4, the pH and also the temperature of drying. The best antacid properties shows the AlPO4 preperation obtained from AlCl3-H3PO4 and NaHCO3-Na2CO3. For comparison, the therapeutic preparate "Aluphos" was also investigated.