A method for preparing iron phosphate with high iron-phosphorus ratio by using pyrite slag

Abstract

The invention discloses a method for preparing ferric phosphate with high iron-phosphorus ratio by utilizing pyrite cinder. The method comprises the following steps: S1, soaking suspended pyrite cinder with water, introducing carbon dioxide until precipitate in the solution is not increased, filtering and irrigating to remove precipitate to obtain slag; S2, reacting the slag with an alkali solvingliquid to remove silicon dioxide to obtain alkali leaching residue; S3, adding excessive acid solving liquid into the alkali leaching residue obtained in the step S2, and reacting to obtain acid leaching solution; S4, adding iron powder into the acid leaching solution to completely convert iron ions in the solution into ferrous ions, adding nonionic flocculating agent after the iron powder is notdissolved, and removing precipitate to obtain a clear ferrite solution; and S5, adding PEG into the ferrite solution to obtain a reaction base solution, adding hydrogen peroxide and phosphate mixed solution into the reaction base solution, and reacting to prepare ferric phosphate slurry. Compared with the prior art, the method has the advantages of smart design, simple operation and high iron-phosphorus ratio of ferric phosphate.

Description

technical field [0001] The invention relates to the technical field of lithium batteries, in particular to a method for preparing ferric phosphate with high iron-phosphorus ratio by using pyrite slag. Background technique [0002] Lithium-ion battery is a new generation of green high-energy battery, and it is also a high-tech product of great significance in the 21st century. It has the advantages of high voltage, small self-discharge, high energy density, and good cycle performance, and has been widely used in mobile phone batteries, electric vehicles and other fields. As one of the four important components of lithium-ion electronics, cathode materials are also an important direction for the current development of lithium-ion batteries. The positive electrode materials of lithium ion batteries in the prior art are mainly lithium cobaltate, lithium manganate, ternary materials and lithium iron phosphate. Among them, lithium iron phosphate batteries are expected to be mains...

AI Technical Summary

Problems solved by technology

Pyrite cinders are rich in iron resources, including Fe 2 o 3 , Fe 3 o 4 , FeO, etc., however, since the pyrite slag also contains SiO 2 、Al 2 o 3 , CaO and other impurities, so that the current application of pyrite slag is limited to the fields of water purifiers, iron-based dyes, cement additives, etc., and the iron resources in the slag have not been fully utilized