The manufacturing approach currently utilized is primarily the neutralization approach, that is, after responding phosphoric acid with potassium hydroxide or potassium bicarbonate and also potassium carbonate, the neutralization remedy is focused to eliminate insoluble matter with the control of the reaction end point, and then After that it is cooled and afterwards took shape, centrifuged and dried out to acquire the item. However, since phosphoric acid is divided right into hot-process phosphoric acid and wet-process phosphoric acid, wet-process phosphoric acid is mainly accomplished by utilizing phosphate rock as well as not natural acid according to the principle of generating weak acid from strong acid. The origin is acquired by filtering system after forming calcium sulfate insoluble issue with various other components such as calcium component.
Nonetheless, due to the fact that the high quality of phosphate rock will certainly influence the high quality of wet-process phosphoric acid, the quality of the phosphoric acid item prepared by wet-process phosphoric acid is unpredictable. At the same time, the impurity material in the obtained phosphoric acid is higher and also the pureness is lower, making When utilizing phosphoric acid prepared by wet-process phosphoric acid to produce potassium phosphate products, it will not just make the purity of potassium phosphate salt lower as well as the top quality unstable, but also trigger the addition of potassium hydroxide or potassium carbonate, Potassium ions in potassium bicarbonate respond with various other impurity components to create insoluble issue, which subsequently causes waste of potassium ions, causing boosted enhancement of potassium hydroxide, potassium carbonate or potassium bicarbonate, leading to greater prep work expenses and also greater resource consumption.
Research is performed on the basis of the existing tripotassium phosphate prep work process, and also a technique for preparing tripotassium phosphate with wet-process phosphoric acid is given, making up the following steps:
( 1) obtain the wet-process phosphoric acid that phosphorus pentoxide concentration is 15%, by examining the material of sulfate radical where, and also include phosphate rock powder where, the add-on of phosphorus rock powder is that the mass proportion with the material of sulfate radical is 1:1, after it responds for half an hour, include ammonia water or feed ammonia gas therein, readjust the pH worth to 3, filter to obtain slurry and also filter deposit;
( 2) Obtain Potassium Hydroxide, Potassium Hydroxide is taken part the slip, the mol ratio of the amount of phosphorus pentoxide in the add-on of controlling Potassium Hydroxide and also wet-process phosphoric acid is 6:1, after its feeding consumption is finished, Regulate the adverse stress to 0 MPa, as well as use a temperature of 85 ° C to evaporate and also crystallize. After a multitude of crystals appear in the service, quit the dissipation, great to room temperature, as well as filter to acquire the mother liquor as well as key product; wash the main product to get tripotassium phosphate.
Explained tripotassium phosphate has a purity of 98.1%. For the washing, the cleaning liquid generated by cleaning is gone back to step 1 as well as combined with wet-process phosphoric acid. For the evaporative formation, the gas produced throughout the formation procedure is taken in by water down phosphoric acid, and after that returns to combine with the wet-process phosphoric acid symphonious 1. Explained weaken phosphoric acid has a concentration of 15%. The mommy liquor is sent out to the compound plant food assembly line; the filter residue is sent to the compound fertilizer assembly line. The potassium hydroxide is added as a strong right into the slurry. The material of phosphorus pentoxide in the phosphate rock powder is not less than 7%. The phosphate rock powder has a bit dimension of 40 mesh.