Method for recovering rare earth metals from waste sulphates

A rare earth metal and sulfate technology, which is applied in the field of rare earth metal recovery from waste sulfate materials, can solve the problem of undisclosed chemical preparation of rare earth compounds and the like, and achieve the effect of cost saving

Inactive Publication Date: 2016-07-13
TEKNOLOGIAN TUTKIMUSKESKUS VTT
View PDF9 Cites 8 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This publication shows the feasibility of separating and refining rare individual rare earth compounds by HGMS technology, but does not disclose the chemical formulation of the rare earth compounds as a necessary pretreatment prior to magnetic separation

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

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for recovering rare earth metals from waste sulphates
  • Method for recovering rare earth metals from waste sulphates
  • Method for recovering rare earth metals from waste sulphates

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0045] Firstly, the phosphogypsum samples were dried in an oven (105 °C, 20 h). Gypsum leachate was then prepared by adding dry phosphogypsum powder to water (50 g / L) and mixing in Erlenmeyer glass flasks for 24 h. The solution obtained was filtered (0.45 μm) in order to remove phosphogypsum particles. The clarified solution was used for sulfate reducing bacteria (SRB) studies. Filled with N through a 0.22 μm pore size filter 2 After anaerobic exposure of the phosphogypsum filtrate to gas for 1 hour, the flask containing the gypsum leachate was sealed with an airtight butyl rubber stopper and the top screw cap was removed. With 0.2g yeast extract and 3.75ml lactate L -1 Correction of phosphogypsum leachate. Pre-grown Desulfovibrio desulfurum was added to a volume of 25 L of phosphogypsum leachate.

[0046] The culture formed a precipitate which was collected by vacuum filtration on a 0.22 μm pore size filter funnel. The precipitate was rinsed from the filter with sterile...

Embodiment 2

[0053] The experiment described in Example 1 was likewise repeated to test the reproducibility of the procedure. In Experiment 2 SRB precipitation, the contents of La, Ce and Y were observed to be 33900, 77300 and 5200 ppm (mg / kg), respectively. The Nd-content of the SRB precipitate was 38900 ppm.

[0054] By using a magnetic separation similar to Experiment 1, the final concentrate is shown in Table 2:

[0055] Table 2. Rare earth metal content in recovered concentrates

[0056] components

[0057] (*) From a separate trial (FI101787B)

Embodiment 3

[0059] Phosphogypsum samples of the same origin as used in the aforementioned patent FI101787B were dried in an oven (105° C., 20 h). Gypsum leachate was prepared by adding dry phosphogypsum powder to water (50 g / L) followed by mixing in Erlenmeyer glass flasks for 24 h. The solution obtained was filtered (0.45 μm) to remove solid phosphogypsum particles. The clarified solution was used for sulfate reducing bacteria (SRB) studies.

[0060] Continuously operated sulfate reduction and REE precipitation experiments were performed in a 0.7-liter UASB (upflow anaerobic sludge bed) column, which was also equipped with a solution circulation line with a powerful pump to regulate the fluidization of the sludge so that Mix and homogenize the sludge in the column if necessary. The column was primed with 500 ml of anaerobic granular sludge from an operating wastewater treatment plant and filled to a total volume of 700 ml with sulphate-enriched water. Microbial activity is ensured by ...

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

The present invention relates to a method for recovering rare earth metals from waste sulphate materials, such as waste gypsum, which is a known secondary resource of rare earth metals and widely present e.g. in areas, where industrial phosphate production takes place. The present invention combines sulphate reduction treatment, such as bioreduction with sulphate reducing bacteria, and magnetic separation, which is based on an exceptionally high magnetic susceptibility of rare earth compounds compared to e.g. calcium compounds in such reductively pretreated gypsum precipitate.

Description

technical field [0001] The present invention relates to the recovery of rare earth metals from spent sulfate material. In particular, the present invention relates to the reductive separation of waste gypsum, including sulfates of calcium and other metals, into its dispersed sulfides, in which form the metal component with high magnetic susceptibility can be recovered by employing magnetic separation. Preferably sulfate reducing bacteria are used for said reducing isolation. Background technique [0002] The pyrogenic apatite mineral is used industrially to make phosphate fertilizers and is a known secondary source of rare earth metals. The rare earth (RE) content of apatite varies between 0.5 and 1% as oxides. Several pilot processes for the recovery of precious rare earth metals in relation to adjacent fertilizer production have been developed, so far without economic success (Jorjanie et al., 2011; Al-Shawi et al., 2002). [0003] The long-dominated fertilizer producti...

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 Applications(China)
IPC IPC(8): C22B59/00C22B7/00C22B3/18B03C1/00B03C1/015B03C1/02C01F17/00C02F1/48C02F101/10C01F17/288
CPCB03C1/015B03C1/02C22B3/18C22B7/00C22B59/00C01F17/288Y02P10/20B03C1/002C02F1/488
Inventor 佩雷蒂·柯卡丽雅诺·马基宁马琳·邦伯格安娜·海特宁莫娜·阿诺德
Owner TEKNOLOGIAN TUTKIMUSKESKUS VTT
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