Preparation method of anhydrous ferric pyrophosphate

Abstract

The invention discloses a preparation method of anhydrous ferric pyrophosphate, wherein the method includes steps of adding 110-120 parts by weight of phosphoric acid in 300 parts by weight of de-ionized water and preparing to be phosphoric acid solution; controlling the solution temperature at 50-80 DEG C, and adding 56 parts by weight of 300 meshes-100 meshes of reduced iron powder under the stirring state and reacting for 3 hours, and then adding the acquired precursor liquid in a nanoscale sand grinding machine; performing ball milling for 2 hours and acquiring turbid liquid of which grain diameter distribution D5 is 200-400 nm; spraying and drying the acquired ball mill turbid liquid at 170 DEG C, and acquiring a spherical precursor powder body; at last, calcining the acquired spherical precursor powder body in the air at 600-800 DEG C for 8 hours, and then acquiring the anhydrous ferric pyrophosphate material. As the raw material for producing the lithium iron phosphate material, the calcining process is not existed with the dewatering process of recrystallization water, thereby overcoming the shortcoming that water and carbon are formed to be water gas and the carbon content in the product is reduced; therefore, the anhydrous ferric pyrophosphate is an ideal raw material for producing lithium iron phosphate in the industry.

Description

technical field [0001] The invention belongs to the field of chemical industry and relates to an iron phosphate, in particular to a preparation method of anhydrous iron orthophosphate. Background technique [0002] As the upstream of the new energy vehicle industry chain, the lithium battery industry has gradually entered a stage of rapid development. Among them, the cost of power lithium batteries accounts for a relatively high proportion of the cost of new energy vehicles, close to 40%. Lithium iron phosphate batteries are relatively safe, and the cost has also dropped significantly in recent years. Considering the maturity and economy of battery technology, the current power batteries for electric vehicles are mainly lithium iron phosphate batteries. [0003] Iron phosphate has a stable structure and has a similar crystal structure and unit cell parameters to lithium iron phosphate. As a precursor for the synthesis of lithium iron phosphate, it can effectively control th...

AI Technical Summary

Problems solved by technology

[0004] Aiming at the above-mentioned technical problems in the prior art, the present invention provides a method for preparing anhydrous ferric orthophosphate, and the method for preparing anhydrous ferric orthophosphate should solve the problem of preparing ferric phosphate materials in the prior art The purity of ferric phosphate is not high, it contains an uncertain amount of crystal water, and the existence of crystal water has some negative effects on the calcination process, the preparation process is complicated, the production cost is high, and the technical problems of component control are difficult.

Images