52 results about "Iron oxalate" patented technology

The invention relates to a method for separating and recovering iron from red mud. The method is characterized by comprising the steps: of leaching out and removing iron from the red mud by using an oxalic acid solution, and filtering to obtain iron-free red mud and an iron oxalate-containing leaching solution, wherein the obtained iron-free red mud can be used as a raw material for producing cement and fireproof bricks; iron oxalate in the obtained leaching solution is reduced to ferrous oxalate through membrane electrolysis or adding a reducing agent and ferrous oxalate is precipitated out, or iron in the solution is separated by directly neutralizing and precipitating an iron hydroxide and oxalate mixture; obtained ferrous oxalate is decomposed to obtain oxalic acid and an iron-containing compound; the obtained iron hydroxide and oxalate mixture is selectively leached out, separated and recovered to obtain oxalic acid and an iron-containing compound; the process of returning recovered oxalic acid to the red mud to leach out and remove iron is cyclically used. The method has the characteristics of short technological process, good iron separation effect, simplicity and convenience in operation, environmental friendliness and the like, and is suitable for large-scale industrialized application.

The invention relates to a method for producing high-purity battery grade iron oxalate by utilizing pickle liquor, comprising the following steps: the pickle liquor is pre-treated for lowering spent acid content, thus leading the pickle liquor to generate ferrite solution with a certain concentration; then after strict filtering and magnetic separation, the ferrite solution is transported into a reaction kettle, then industry ammonia is added and the solution is stirred for reaction to generate ferrous hydroxide gelatin; the soluble oxalic acid solution is slowly added in and stirred, and then the mixture is stirred by a conversion reaction kettle and heat preservation is carried out, thus obtaining iron oxalate slurry after reaction; iron oxalate mother solution is separated in the iron oxalate slurry, and the separated iron oxalate is washed, dried and crashed for obtaining high-purity superfine iron oxalate products. The method has the beneficial effects that: the pickle liquor in industrial production is fully utilized; a two-step liquid phase method of oxidation and conversion is adopted for leading the reaction to be more fully, so that the reaction rate is greatly improved,the grain diameter of the finished products iron oxalate is fine and uniform, D50 is less than or equal to 5mum, and the content of the iron oxalate is more than or equal to 95.5 percent; furthermore, the pickle liquor is used as raw material, and cyclic utilization and environmental protection of the industrial waste are utilized, thus changing waste into valuable and greatly lowering the production cost.

The invention belongs to the technical field of industrial waste recycling and specifically relates to a method for synchronously and efficiently extracting high-value rare earth and iron from NdFeB waste for reuse. The method of the present invention reacts the oxidation product obtained after oxidizing and roasting the NdFeB waste with the oxalic acid solution to obtain the leach solution containing iron oxalate and the solid precipitate mainly composed of rare earth oxalate, and then only the leach solution and the precipitate Iron reduction and molten salt electrolysis treatment can be carried out respectively to obtain rare earth alloys for the production of NdFeB materials and ferrous oxalate for the production of lithium battery materials. The method only uses oxalic acid solution as a leaching agent and a precipitating agent, and can complete the leaching of iron and the transformation of rare earths in one step, thereby achieving the purpose of simultaneously realizing the efficient extraction and high-value recycling of iron and rare earths. The method of the invention has a short extraction process, is environmentally friendly, can effectively recover and obtain high-value products, and has extremely high process operability.