Neodymium, iron and boron waste recycling process with approximately zero wastewater discharge

Abstract

The invention discloses a neodymium, iron and boron waste recycling process with approximately zero wastewater discharge. The method is characterized in that recycling and separating for neodymium, terbium, dysprosium and cobalt in neodymium, iron and boron waste are researched, means such as fine grinding and crushing for the waste, oxidizing roasting, prior dissolution in hydrochloric acid, neutralization and impurity removal, double-salt iron settling and extraction separation are selected according to chemical properties of elements contained in the waste, valuable elements in the neodymium, iron and boron waste are successfully extracted, and neodymium oxide, terbium oxide, dysprosium oxide and cobalt oxide which are high in purity are obtained. The neodymium, iron and boron waste recycling process is simple, the production cost is low, an obvious economical benefit is realized, environmental pollution is prevented, and the process is applicable to industrial continuous production. Besides, the extraction rates of manufactured neodymium oxide, terbium oxide, dysprosium oxide and cobalt oxide products are maximized, and quality indexes of the manufactured neodymium oxide, terbium oxide, dysprosium oxide and cobalt oxide products meet industrial standards or customer standards.

Description

technical field [0001] The invention relates to a NdFeB waste recovery process close to zero discharge of waste water. Background technique [0002] NdFeB is a kind of permanent magnet material with superior performance, which is widely used in various fields. Due to the factors of production process, about 20% of waste will be generated during production and use. NdFeB materials contain about 30% of rare earth elements (including about 90% of neodymium, and the rest are terbium, dysprosium, etc.), and some NdFeB materials contain another 2% ~ 3% cobalt element. The recycling of NdFeB materials not only makes reasonable use of resources, but also reduces environmental pollution. At present, some rare earths have been recovered by double salt precipitation, alkali conversion and other processes, but the recovery rate of heavy rare earths is low: others have used sulfuric acid dissolution, double salt precipitation rare earths, alkali conversion, hydrochloric acid dissolutio...

AI Technical Summary

Problems solved by technology

At present, some rare earths have been recovered by double salt precipitation, alkali conversion and other processes, but the recovery rate of heavy rare earths is low: others have used sulfuric acid dissolution, double salt precipitation rare earths, alkali conversion, hydrochloric acid dissolution, extraction and separation to recover rare earths , but because of the low metal recovery rate, large consumption of chemical materials, and high cost, a large amount of liquid waste and solid waste are generated in the process of acid hydrolysis and alkaline hydrolysis, causing secondary pollution to the environment and restricting the scale of the process. use

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