Method for continuously producing potassium dihydrogen phosphate and co-producing formic acid

Abstract

The invention discloses a method for continuously producing potassium dihydrogen phosphate and co-producing formic acid. The method comprises the following steps: first feeding potassium formate, perphosphoric acid and an efficient depolymerizing agent into a spiral mixer simultaneously, and uniformly stirring and mixing the materials to carry out reaction on the materials: after being gathered, produced formic acid gas overflows from a gas exhaust opening; controlling the mixing and stirring time of the spiral mixer, pressing the materials into a distilling dryer, and after distilling drying is completed, preparing compound dry potassium phosphate powder; washing the produced formic acid gas in a washing and dewatering purifier through perphosphoric acid, putting the purified formic acid gas into a condenser, collecting condensed formic acid to prepare various types of high-concentration formic acid, and extracting and discharging non-condensed gas; enabling the compound dry potassium phosphate powder to automatically flow out of the distilling dryer, and directly preparing a potassium dihydrogen phosphate dry powder product from the dry powder or preparing a solution product from a solution prepared by adding water into the dry powder. By the adoption of a continuous process, the production efficiency of the whole process is improved, and the yield of the potassium dihydrogen phosphate and the concentration of the formic acid are increased; the production cost is reduced, and higher economical benefits are achieved. The method is applicable to an enterprise producing the potassium dihydrogen phosphate.

Description

technical field [0001] The present invention relates to aliphatic carboxylic acids and alkali metal phosphates, in particular, to methods for producing formic acid and potassium phosphate salts. Background technique [0002] Potassium dihydrogen phosphate ( Potassium Phosphate Monobasic ) Chemical formula: KH 2 PO 4 , colorless tetragonal crystal or white crystalline powder, used as buffering agent and culture agent in industry; used as high-efficiency phosphorus-potassium compound fertilizer in agriculture; food grade used as food improvement additive. Formic acid ( Formic acid, Methanoic acid ), also known as formic acid, molecular formula is HCOOH, colorless, pungent odor liquid, in industry, formic acid is used in rubber, medicine, dyes, leather, etc. [0003] For the method of preparing formic acid and co-producing phosphate, there are already No. ZL97103209.2 "Method for producing formic acid and co-producing various sodium phosphate salts by acidifying sodium for...

AI Technical Summary

Problems solved by technology

However, some of these technologies use sodium formate and superphosphoric acid as raw materials to produce formic acid and co-produce various sodium phosphate salts, and some are synthesized by CO; however, in recent years, sodium phosphate salts have been affected by overcapacity, market competition has intensified, and the products have become unprofitable. profit, even loss

Images