The invention discloses a manufacturing technology of magnesium metaphosphate, which comprises the following steps: putting the raw material of MgO or 4MgCO3Mg (OH) 25H2O in the autoclave to stir with the deionized water; heating; adding 85-98 percent H3PO4 to make raw material dissolve completely and pH value at 2.5-3 (approaching 3); shifting in the extractor after diluting and cooling; adding dense HCL; mixing the C12H27O4P and 80# petrol to extract; immigrating the water-liquid into reacting container; removing the HCL by heating; filtering; heating the autoclave to concentrate the Mg(H2PO4)3 content ranged from 55 to 60 percent; shifting the material in the spray drying tower to compress into magnesium metaphosphate after filtering. The invention simplifies the manufacturing technology and reduces the cost, which improves the production rate by more than 99 percent. |