Method for dissolving out rare-earth by treating waste neodymium-iron-boron materials

Abstract

The invention discloses a method for dissolving out rare-earth by treating waste neodymium-iron-boron materials. The method comprises the following steps of: crushing materials into powder, wetting and dispersing by using an electrolyte solution, and carrying out size mixing; then controlling electric potential between +400 mV and +800 mV by adding an oxidizing agent, and controlling pH between 2.5 and 4.5 by adding inorganic acid; leaching for 30-80 minutes under the condition that the temperature is 50-90 DEG C; after the leaching is completed, carrying out solid-liquid separation and filter residue washing; purifying, enriching and separating the rare-earth from leach liquor with solid leaching residues separated, wherein filter residues are taken as raw materials used for producing iron products after being washed. The method disclosed by the invention improves the extraction rate of the rare-earth and is convenient for extracting the rare-earth subsequently by adopting multiple methods by adopting subacid oxidizing leaching, reduces the usage amount of acid, alkali and other chemicals, does not adopt the high-temperature oxidation method and reduces the energy consumption.

Description

technical field

[0001] The invention relates to a method for separating and extracting valuable substances from recycled resources, and belongs to the field of resource recycling. Specifically, it relates to a method for dissolving rare earths from waste neodymium-iron-boron materials. Background technique

[0002] NdFeB permanent magnet material, known as the "magnet king", has excellent magnetic properties and is widely used in many fields. NdFeB materials contain rare earth metals such as metal neodymium or praseodymium neodymium alloy, and metal dysprosium, which is the largest market area for rare earth applications in modern materials; my country's current annual output of NdFeB permanent magnet materials has exceeded 100,000 tons, and the use of rare earth metals exceeds 30,000 tons. In the production process of NdFeB magnets, NdFeB waste (including turning blocks and oil-immersed waste, etc.) is produced, which is about 20% of the weight of raw materials. At presen...

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