Solubility in manganese sulfate-ammonium sulfate-water system
Abstract
The production of phosphorus-containing fertilizers involves the use of mineral acids and phosphate raw materials. In the production process and finished fertilizers, the existence of calcium phosphates, ammonium, sulfuric or nitric and phosphoric acids is possible. Enriched superphosphate contains monocalcium phosphate, calcium sulfate dihydrate, phosphoric acid. During ammoniation, monoammonium phosphate can also be formed. The solubility of the components in the manganese sulfate-ammonium sulfate-water system was studied by the visual-polythermal method in the temperature range from -1.0°С to 27.0°С. The phase diagram limits the regions of ice crystallization, ammonium sulfate, manganese sulfate and chemical compound. A solubility diagram was plotted and a new compound (ammonium sulfate + marganes sulfate + water) (NH 4 ) 2 Mn(SO 4 ) 2 *6H 2 O was isolated. The new compound was identified by chemical, X-ray diffraction, thermogravimetric and IR spectroscopic analyses. To physicochemically substantiate the behavior of marganese sulfate under the conditions of production of enriched superphosphate, the interaction of marganese sulfate with monocalcium phosphate was studied by the method of isomolar series in 0.01 M solutions.