Method for comprehensively recycling various rare earth from rare earth materials containing fluorine

Abstract

The invention relates to a method for comprehensively recycling various rare earth from rare earth materials containing fluorine, in particular to a comprehensive utilization treatment separating method for cerium fluoride, fluorine cerium oxide, deep smelting slag and iron thorium slag, and belongs to the technical field of non-ferrous metal rare earth separation. The method for comprehensively recycling various rare earth from rare earth materials containing the fluorine comprises the following steps: a. stirring the rare earth materials containing the fluorine with sulfuric acid to generate hydrofluoric acid gas for preparing cryolite or hydrofluoric acid; and b. obtaining sulfuric rare earth solution by dipping the materials after stirring through water. The sulfuric acid directly acts on bastnaesite after roasting or other rare earth materials containing the fluorine (a cerium fluoride or fluorine cerium oxide product, the deep smelting slag and the iron thorium slag which are generated after reactions), further roasting is not required, a fluorine product is directly recycled through generated gas after the reactions at normal temperature, and the procedure in the prior art that sodium fluoride is formed by transforming alkali into fluorine and removed through washing is not required. The problem of environment protection of discharging of the fluorine is effectively solved, and the high yield of the rare earth is ensured.

Description

technical field [0001] The invention belongs to the technical field of rare earth separation of non-ferrous metals, and in particular relates to a comprehensive utilization treatment and separation method of cerium fluoride cerium oxyfluoride, deep-dissolved slag and iron thorium slag. Background technique [0002] With the continuous expansion of the scale of the rare earth industry, problems such as low resource utilization and serious pollution in the processing of rare earth resources are becoming more and more serious. [0003] At present, the separation of cerium and other rare earths in the industry mainly adopts oxidation roasting, first-time optimal dissolution, filtration, alkali transfer of filter residue, water washing, second-time optimal dissolution, three-time optimal dissolution, and filtration to obtain cerium-less rare earth chloride and cerium enrichment. To achieve the purpose of defluorination, process ① see figure 1 . [0004] The process first decomp...

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Problems solved by technology

[0027] This process has the following problems and deficiencies: the ore after roasting has undergone many times of optimal melting, alkali conversion, water washing, and filtration, and the process is long: due to the long process and high cost, repeated material handling, labor intensity is high; the filter residue needs to be washed after alkali conversion , after washing, a large amount of fluorine-containing subtractive wastewater is produced, which seriously pollutes the environment, and the treatment cost is high and difficult

[0044] The above two processes have something in common: the cerium-less rare earth chloride solution needs to be neutralized to remove impurities, and the purpose of settling iron and thorium can be achieved by adjusting the pH value to 4-4.5, and some rare earths will form hydroxide rare earths to settle, especially free in the solution. Fluoride ions will complex some rare earths to form rare earth fluorides and mix them into iron thorium slag, resulting in loss of rare earths

In addition, the cerium-rich slag obtained in process ① is prepared through deep dissolution to produce cerium chloride products, which will produce "deep dissolution slag"

There will be some rare earths in the deep melting slag, resulting in the loss of rare earths

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