Method for preparing metal magnesium by silicothermic process

A reduction method and metal magnesium technology are applied in the field of inorganic salt chemical industry, which can solve the problems of endangering the safety of operators, environmental pollution, and high requirements for anti-corrosion of equipment, and achieve the effects of high utilization rate and high total yield.

Inactive Publication Date: 2010-04-28
QINGHAI INST OF SALT LAKES OF CHINESE ACAD OF SCI
View PDF1 Cites 14 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This technology uses spray drying and calcining magnesium chloride to prepare metal magnesium. The process will produce a large amount of hydrogen chloride corrosive gas, which requires high corrosion resistance of equipment, and may cause environmental pollution and endanger the safety of operators.

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

[0028] Embodiment 1, get 70ml saturated magnesium chloride solution (concentration is 4.7497mol / L), add 490ml water (dilute to 8 times volume, magnesium chloride concentration is 0.5937mol / L), add 40g lime (magnesium chloride / lime mol ratio is 1: 2.08 ), stirred for 4 hours. Settled for 20 minutes, vacuum filtered, washed once with 70ml of water, and dried. The calcium-magnesium ratio in the calcium-magnesium mixed hydroxide generated is 1:1.05, Cl - The content is 1.0%, and the magnesium yield is 100%. The calcium-magnesium mixed hydroxide was placed in a horse boiling furnace and calcined at 800° C. for 4 hours to obtain the calcium-magnesium mixed oxide with a water activity of 36.02%. Mix this calcium magnesium mixed oxide with 75% ferrosilicon, fluorite (CaF 2 ) were mixed at a mass ratio of 80.46%, 16.45%, and 3.09%, respectively, and dry-milled with a ball mill until the particle size was 90% and passed through a 200-mesh sieve, and then pressed into tablets under a ...

Embodiment 2

[0029] Embodiment 2, get 70ml saturated magnesium chloride solution (concentration is 4.7497mol / L). Get 40g of lime, add 450ml of water, stir to prepare lime slurry. The obtained lime slurry was mixed and reacted with saturated magnesium chloride solution (magnesium chloride / lime molar ratio was 1:2.08), stirred for 0.5 hour to obtain jelly, which was vacuum filtered. After filtering, wash with 70ml of water each time, wash 3 times in total, and dry. The calcium-magnesium ratio in the generated calcium-magnesium mixed hydroxide is 1:1.39, Cl - The content is 10.08%, and the magnesium yield is 100%. The calcium-magnesium mixed hydroxide was placed in a horse boiling furnace and calcined at 800° C. for 4 hours to obtain a calcium-magnesium mixed oxide with a water activity of 34.91%. Mix this mixed oxide with 75% ferrosilicon, fluorite (CaF 2) were mixed at a mass ratio of 80.46%, 16.45%, and 3.09%, and dry-milled with a ball mill until the particle size was 90% and passed t...

Embodiment 3

[0030] Embodiment 3, get 70ml saturated magnesium chloride solution (concentration is 4.7497mol / L), add 350ml water (dilute to 6 times volume), add 40g lime (magnesium chloride / lime molar ratio is 1: 2.08), stir 4 hours. Settled for 20 minutes, centrifugally filtered, washed once with 70ml of water, and dried. The calcium-magnesium ratio in the calcium-magnesium mixed hydroxide generated is 1:1.06, Cl - The content is 1.6%, and the magnesium yield is 100%. The calcium-magnesium mixed hydroxide was placed in a horse boiling furnace and calcined at 800° C. for 4 hours to obtain a calcium-magnesium mixed oxide with a water activity of 36.02%. Mix this mixed oxide with 75% ferrosilicon, fluorite (CaF 2 ) are mixed at a mass ratio of 80.46%, 16.45%, and 3.09%, dry-milled with a ball mill until the particle size is 90%, and passed through a 200-mesh sieve, and then pressed into tablets with a tablet machine under a pressure of 200MPa, and then placed in a vacuum tank. Reduction w...

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 provides a new method for preparing metal magnesium by a silicothermic process and by using bischofite from the seawater salt making or salt lake brine salt and potassium chloride making as a raw material. The method comprises the steps of: reacting lime and solution of magnesium chloride to generate a calcium-magnesium mixed hydroxide; calcining the calcium-magnesium mixed hydroxide to obtain a calcium-magnesium mixed oxide; finely grinding the mixture of calcium-magnesium mixed oxide, silicon iron and fluorite in a ball mill, pressing the ground mixture into a walnut shape or a sheet shape on a forming press, and reducing the walnut-shape or sheet-shape mixture under vacuum in a magnesium smelting reduction pot to obtain the magnesium crystalline; and finally refining the magnesium crystalline, casting the refined magnesium crystalline into ingot, and performing surface treatment to obtain a magnesium metal ingot. The method overcomes the defect that a great amount of carbon dioxide greenhouse gas is exhausted in the Pidgeon process for calcining dolomite, avoids the problem of preparing anhydrous magnesium chloride by an electrolytic process, overcomes the defect that the direct calcining of bischofite gives corrosive and toxichydrogen chloride gas, has low requirements on equipment and is clean, environmentally-friendly and safe in production. The method can also be applied to the field of alkaline waste liquor treatment and comprehensive utilization.

Description

technical field [0001] The invention belongs to the technical field of inorganic salt chemical industry, and relates to a method for preparing magnesium metal, in particular to a method for preparing magnesium metal by using magnesium chloride as a raw material, and more specifically to a by-product magnesium chloride old brine or water after using brine to make salt. Magnesium is used as raw material, and the metal magnesium is prepared by silicothermal reduction method. technical background [0002] The structural properties of magnesium metal are similar to that of aluminum, and it has various uses of light metals. It can be used as an alloy material for aircraft and missiles, and it will be the main metal material in the future. The production methods of metal magnesium mainly include the Pidgeon method using dolomite as raw material and the electrolysis method using magnesium chloride as raw material. The production of magnesium metal by the dolomite method is to obtai...

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): C22B26/22C22B5/04
Inventor 龙光明何志贾优良祁米香杨占寿王舒娅
Owner QINGHAI INST OF SALT LAKES OF CHINESE ACAD OF SCI
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