Extraction process for reactive metal oxides

A process method and oxide technology, applied in chemical instruments and methods, preparation of titanium oxide/hydroxide, alkali metal aluminate/aluminum oxide/aluminum hydroxide, etc., can solve unfavorable iron-carbon oxide and oxidation Phase distribution and other issues, to achieve the effect of economic recovery and reduce the impact on the environment

Active Publication Date: 2006-07-19
UNIV OF LEEDS
View PDF7 Cites 12 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the extraction of TiO from the reduced ore 2 Exhibits unf

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
  • Extraction process for reactive metal oxides
  • Extraction process for reactive metal oxides
  • Extraction process for reactive metal oxides

Examples

Experimental program
Comparison scheme
Effect test

Embodiment I

[0085] Example I: Bauxite from Ghana

[0086] attached Figure 1a The implementation process of embodiment 1 is represented schematically.

[0087] Gray cast iron containing 1% silicon (Si) and 4.2% carbon is melted in an induction furnace. Ghana bauxite (approximate composition: 55% Al 2 o 3 , 12% Fe 2 o 3 , 2% TiO 2 , 2% SiO 2 and water) mixed with lime and excess carbon, and slowly added to the molten slurry. The temperature of the molten slurry is adjusted to maintain the metal-bearing slag in a molten state.

[0088] Sodium carbonate or potassium carbonate (20% over stoichiometric ratio) is added in the final stage of the reduction reaction and a fluid slag is released. The slag is digested with hot water and filtered. The filtrate is acidified with carbon dioxide to convert the water-soluble sodium / potassium aluminate to Al(OH) 3 precipitation. Filter out Al(OH) 3 and roasted to produce pure Al 2 o 3 . The extraction efficiency of alumina is close to 65%....

Embodiment II

[0091] Embodiment II: (red mud)

[0092] Accompanying drawing 1 has represented the implementation process of embodiment II schematically.

[0093] Red mud (approximate composition: 46% Fe 2 o 3 , 22% Al 2 o 3 , 8% TiO 2 , 8% SiO 2 , 3 to 4% of MgO and CaO and the loss on ignition of 10 to 12%) are added to the molten gray cast iron slurry together with excess lime and carbon. Sodium carbonate / potassium carbonate (more than 20% of the stoichiometric ratio) is added to the slag before tapping. Experiments were carried out according to the methods described in the above examples. The extraction efficiency of alumina exceeds 75%. About 75% TiO in this process 2 is extracted. The residue contains aluminosilicate complexes.

[0094] The red mud obtained in this example contains alkali in the form of potassium ions, unlike soda in red mud which can neither be used as a fertilizer nor as a soil conditioner to exhibit harmful effects.

Embodiment III

[0095] Embodiment III: (alkali-roasted ilmenite)

[0096] attached figure 2 The implementation process of embodiment III is schematically represented.

[0097] Contains 63% TiO 2 , 32% Fe 2 o 3 and 2% Al 2 o 3 The ilmenite ore is mixed with 10% alumina and excess alkali metal carbonate, and roasted in air at 1200°C for 2 hours. Add sodium carbonate or potassium carbonate (more than Na 2 O:TiO 2 20% of the stoichiometric ratio). The calcined material was extracted with water and the solution was filtered to separate the residue. The filtrate is acidified with carbon dioxide to convert the water-soluble sodium / potassium aluminate to Al(OH) 3 precipitation. Filter out Al(OH) 3 And recycle to the first step. The filtrate was evaporated and sodium carbonate was recovered. The residue containing titanium dioxide (TiO2) was leached with 5% HCl solution. The residue was filtered and washed with acid solution and then with water. At the end of the process, TiO in the r...

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 zero-waste process for extraction of alumina from different types of bauxite ores and red mud residues and of titanium dioxide from ilmenite. Iron oxide is first reduced to metallic iron above the melting point of C-saturated cast iron alloy which yields a high-C iron alloy and an Al and Ti metal oxide rich slag which is then treated with alkali carbonate to form alkali aluminates and titanates. The alkali aluminates are separated by water leaching from which the hydroxide of alumina is precipitated by bubbling C02. The residue from water leaching is treated with sulphuric acid and Ti02 is precipitated via a hydrolysis route. The process recovers most of the metal values and generates only small quantities of silicious residues at pH 4-5 which can be used for soil conditioning. The present also relates to a method for selective separation of Ti02-rich oxides from titaniferrous ore/residue materials via oxidative roasting in the presence of alkali carbonate or carbonates followed by aqueous leaching of the roasted material and selective precipitation of Ti02 under controlled condition below pH=4.

Description

technical field [0001] The invention relates to a process for recovering metal oxides from titanium dioxide-rich and / or alumina-rich mixtures, and to a method for recovering titanium dioxide from titanium dioxide-containing composites. Background technique [0002] Existing extracted alumina and TiO 2 This process produces large amounts of hazardous waste that is disposed of in landfills. The management of landfill sites is a major challenge due to increasingly stringent environmental regulations. [0003] The Bayer process for extracting alumina from bauxite is well described (Technology Roadmap for Bauxite Residue Treatment and Utilisation, February 2000, The Aluminum Association see webpage http: / / www.aluminum.org ; Fathi Habashi, editor-in-chief, Handbook of Extractive Metallurgy, Volume 2, Wiley-VCH Publishing, Berlin, 1997; Adamson et al., Basic Principles of Bayer Process Design, Extractive Metallurgy of Aluminum, Volume 1, Interscience Publishing, New York, 1963 ;...

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
IPC IPC(8): C01G23/047C01F7/14C01F7/38C22B34/12C22B7/00C01G49/06C01F7/142C22B1/02C22B5/10C22B7/04C22B21/00
CPCC22B21/0038C22B1/02C01G49/06C01F7/142C22B34/1209C22B5/10C22B7/04C22B34/1259C01F7/38C22B34/1236C01G23/047Y02P10/20
Inventor 安尼梅西·扎派勒·安东尼·梅尔潘维拉斯·戴特雷·塔萨瓦德卡
Owner UNIV OF LEEDS
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