A kind of method for resource management of rare earth oxalic acid precipitation wastewater

A technology for oxalic acid precipitation and recycling, which is applied in the field of rare earth oxalic acid precipitation wastewater recycling and can solve problems such as mutual pollution of organic phases.

Active Publication Date: 2021-05-14
CENT SOUTH UNIV +1
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, due to the use of various extraction systems in the process, the organic phase is easily contaminated with each other during use.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0021] Take the HCl concentration as 1.5mol / L H 2 C 2 o 4 Rare earth oxalic acid precipitation wastewater with a content of 10.5g / L 5m 3 , 65 ℃ stirring to add oxalic acid crystals, first H 2 C 2 o 4 The concentration of hydrochloric acid was increased to 65g / L, cooled and filtered, and the precipitated rare earth oxalate was separated, and then HCl gas was passed into the obtained filtrate to increase the concentration of hydrochloric acid to 10.5mol / L, cooled and crystallized at room temperature for 16 hours, and oxalic acid crystals and h 2 C 2 o 4 The hydrochloric acid content is 0.95g / L and the concentration of hydrochloric acid is 9.8mol / L after crystallization. The obtained oxalic acid crystals continue to be used for rare earth precipitation. After the crystallization liquid is added with an appropriate amount of oxidant to remove the residual oxalic acid, it is used for the decomposition of rare earth ores. Process The recovery rate of oxalic acid (oxalic acid...

Embodiment 2

[0023] Take the HCl concentration as 1.9mol / L H 2 C 2 o 4 Rare earth oxalic acid precipitation wastewater with a content of 14.1g / L 3m 3 , stir and add 10mol / L hydrochloric acid, increase the concentration of hydrochloric acid to 4.8mol / L, freeze and crystallize at -20°C for 8h, filter to obtain oxalic acid crystals and H 2 C 2 o 4 The post-crystallization solution with a content of 99.7%, and the recovery rate of hydrochloric acid is >99.5%.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

A method for resource management of rare earth oxalic acid precipitation wastewater. Firstly, oxalic acid is added to oxalic acid precipitation wastewater, and the same ion effect generated by oxalic acid and ions is used to force the residual rare earth to precipitate out, and the rare earth oxalic acid precipitate and its precipitated solution are filtered. , and then add hydrochloric acid or HCl gas into the precipitated liquid to increase the acidity of the solution, and freeze to force the crystallization of oxalic acid in it, and use the characteristic that the solubility of oxalic acid decreases with the increase of solution acidity and the decrease of temperature to realize the combination of oxalic acid and hydrochloric acid separation. The invention has the advantages of cleanness and environmental protection, economical efficiency and the like, and is suitable for industrial application in the treatment of oxalic acid precipitation wastewater in the rare earth smelting process.

Description

technical field [0001] The invention belongs to the field of metallurgy and chemical industry, and in particular relates to a method for recycling rare earth oxalic acid precipitation wastewater. Background technique [0002] The rare earth smelting process generally uses hydrochloric acid to dissolve rare earth oxides, hydroxides and carbonate minerals, and then separates the rare earth chloride product solution through solvent extraction, and then the rare earth chloride product solution is precipitated by oxalic acid or sodium carbonate to obtain rare earth oxalate or carbonate. The oxalic acid precipitation process is widely used in the production of rare earth products because of its good removal effect of non-rare earth impurities. [0003] The rare earth oxalic acid precipitation process is to first mix the oxalic acid solution with the rare earth chloride product solution to generate hydrochloric acid and rare earth oxalic acid precipitation. Filter and wash to obt...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Patents(China)
IPC IPC(8): C02F1/66C02F101/34
CPCC02F1/66C02F2101/34
Inventor 王学文孟钰麒王懿王明玉杜艳苹
Owner CENT SOUTH UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap