Method for selectively leaching scandium and sodium from bayer red mud

A Bayer red mud and selective technology, applied in the direction of improving process efficiency, can solve the problems of non-recyclable, complex process, large acid consumption, etc., and achieve the effect of reducing consumption, cost and requirement

Active Publication Date: 2016-11-09
UNIV OF SCI & TECH BEIJING
View PDF8 Cites 22 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Most current recycling processes are not selective for valuable metal elements; moreover, most processes are complex, acid-intensive and non-recyclable

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 selectively leaching scandium and sodium from bayer red mud
  • Method for selectively leaching scandium and sodium from bayer red mud

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0034]A method for selectively leaching scandium and sodium from Bayer red mud, said method comprising the following steps:

[0035] (1) Mix Bayer red mud with concentrated sulfuric acid with a mass fraction of 65% according to the ratio of solid to liquid 1 g: 1.5 (g:ml), and use sulfuric acid to completely salinize Bayer red mud under low temperature conditions, so that red Mud minerals are converted into corresponding sulfates to obtain sulfated red mud; the salinization conditions are as follows: temperature 120 °C, holding time 20 minutes;

[0036] (2) Roasting the mineral salted red mud prepared in step (1) at a medium temperature, and obtaining roasted products by virtue of the different mineral decomposition temperatures of different sulfates in the sulfated red mud, and the roasted products include easy Dissolved scandium and sodium sulfate and impurity minerals that are not easily soluble; the impurity minerals include iron oxides and aluminum oxides; the conditions ...

Embodiment 2

[0041] A method for selectively leaching scandium and sodium from Bayer red mud, said method comprising the following steps:

[0042] (1) Mix Bayer red mud with concentrated sulfuric acid with a mass fraction of 75% according to the ratio of solid to liquid 1: 1.5 (g:ml), and use concentrated sulfuric acid to completely salinize Bayer red mud under low temperature conditions, so that Red mud minerals are transformed into corresponding sulfates to obtain sulfated red mud; the salinization conditions are as follows: temperature 150 °C, holding time 20 minutes;

[0043] (2) Roasting the mineral salted red mud prepared in step (1) at a medium temperature, and obtaining roasted products by virtue of the different mineral decomposition temperatures of different sulfates in the sulfated red mud, and the roasted products include easy Dissolved scandium and sodium sulfate and impurity minerals that are not easily soluble; the impurity minerals include iron oxides and aluminum oxides; t...

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 invention mainly belongs to the technical field of pyrogenic process-hydrometallurgy and particularly relates to a method for selectively leaching scandium and sodium from bayer red mud. By the adoption of the method, the scandium, a rare and expensive metallic element, and sodium high in content can be leached from the red mud, and separation of the scandium and the iron element in the red mud can also be achieved. According to the method, based on the occurrence form of the scandium in the red mud, the bayer red mud is evenly mixed with concentrated sulfuric acid, after low-temperature sulphating is conducted, medium-temperature calcinating is conducted, and escaping sulfur trioxide and sulfur dioxide or sulfuric acid are recycled during sulphating and medium-temperature calcinating; and after sulfate impurities are decomposed, a washing liquor rich in the scandium and the sodium and low in iron content is obtained through water leaching. The washing liquor, prepared through the method, rich in the scandium and the sodium and low in iron content provides absolute advantages for the follow-up steps of ion exchange and solvent extraction and re-extraction; and after solid-liquid separation, the obtained leaching residues high in iron content and low in sodium content can be used as a building material or a raw material of blast furnace iron making. Besides, the sulfuric acid used as the reagent in the method can be recycled and reused, and therefore no new pollution is generated.

Description

technical field [0001] The invention mainly belongs to the technical field of pyro-hydrometallurgy, and specifically relates to a method for selectively leaching scandium and sodium from Bayer red mud. Background technique [0002] Bayer red mud is a by-product produced during the extraction of alumina from bauxite in the Bayer process. In 2015, the global output of metallurgical grade alumina was about 1.08 million tons, and the red mud production last year was estimated to be about 1.1 million to 2 million tons. There are many kinds of valuable elements in Bayer red mud, such as iron, aluminum, sodium, titanium, calcium and rare and precious metals, among which the iron content is generally between 7 and 72%. Due to its high alkalinity, presence of heavy metals and radioactive elements, simply stacking red mud not only takes up space but may cause environmental problems such as groundwater pollution, dust and other accidents. [0003] Sodium ions are finally accumulated ...

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): C22B7/04C22B1/06C22B59/00C22B26/10
CPCC22B1/06C22B7/006C22B7/04C22B26/10C22B59/00Y02P10/20
Inventor 李宏煦刘召波贾东民黄蒙蒙张娜
Owner UNIV OF SCI & TECH BEIJING
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