Production process of potassium dihydrogen phosphate

Abstract

The invention discloses a production method for potassium dihydrogen phosphate, which essentially comprises: A. yellow phosphorus and oxygen combust in a combustion chamber; B. potassium hydroxide solution and / or the mother liquor for producing potassium dihydrogen phosphate absorb phosphorous pentoxide in a hydration tower under negative pressure, compress and generate a mixture of phosphoric acid and potassium dihydrogen phosphate; C. the mixture is sent to a reaction crystallizer, potassium hydroxide solution is added to the reaction crystallizer to adjust the pH value; the mixture is cooled and crystallized to separate potassium dihydrogen phosphate; the separated mother liquor is returned to the step B to be as the absorbent of the phosphorus pentoxide. The method has the essential advantages of solving the problem of large amounts of energy consumption in the process of compressing potassium hydroxide solution and producing potassium dihydrogen phosphate mother liquor of the existing production method for potassium dihydrogen phosphate, greatly reducing production cost by 600RMB per ton, saving resources and improving production environment.

Description

Technical field: [0001] The invention relates to a production method of potassium dihydrogen phosphate, in particular to a method for producing potassium dihydrogen phosphate by absorbing phosphorus pentoxide with potassium hydroxide solution and / or mother liquor for producing potassium dihydrogen phosphate. Background technique: [0002] At present, the production method of potassium dihydrogen phosphate is to adopt the neutralization method of traditional potassium hydroxide and thermal phosphoric acid. Although the method has simple process, short production cycle, high product quality and low investment; but because the potassium raw material used is The unconcentrated 30% potassium hydroxide in the potash factory or the concentrated 48% and 50% potassium hydroxide after secondary processing in the potash factory need to evaporate a large amount of water during production, resulting in high energy consumption, heavy pollution and high cost. Other methods such as: extract...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is in order to overcome the deficiency of existing production technology, provides a kind of method that absorbs phosphorus pentoxide to produce potassium dihydrogen phosphate with potassium hydroxide solution and / or the mother liquor of producing potassium dihydrogen phosphate, utilizes yellow phosphorus to burn , Phosphorus pentoxide and potassium hydroxide participate in the chemical reaction to release heat to evaporate potassium hydroxide solution or produce water in the mother liquor of potassium dihydrogen phosphate, and use potassium hydroxide solution or produce water and pentoxide in the mother liquor of potassium dihydrogen phosphate Diphosphorus and potassium hydroxide react to produce potassium dihydrogen phosphate, which solves the problems of evaporating a large amount of water and high energy consumption in the existing production process of potassium dihydrogen phosphate, reduces production costs, saves resources, and reduces pollution

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