Method for preparing magnesium hydroxide utilizing light-burned dolomite powder

A light-burned dolomite powder and magnesium hydroxide technology, which is applied in the direction of magnesium hydroxide, can solve the problems of difficult control of the ratio of strong alkali and uneven structure of magnesium hydroxide, and achieve easy control of reaction conditions, environmental protection, and high purity high effect

Inactive Publication Date: 2011-11-30
WUHAN IRON & STEEL (GROUP) CORP +1
View PDF4 Cites 11 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the structure of the magnesium hydroxide prepared by this patent is not uniform, and i

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 preparing magnesium hydroxide utilizing light-burned dolomite powder
  • Method for preparing magnesium hydroxide utilizing light-burned dolomite powder
  • Method for preparing magnesium hydroxide utilizing light-burned dolomite powder

Examples

Experimental program
Comparison scheme
Effect test

Example Embodiment

[0024] Example 1

[0025] 1) Pour 60g of lightly burned dolomite powder into 1 liter of water at 70°C and digest it for 40 minutes to obtain lightly burned dolomite lime emulsion;

[0026] 2) Pour carbon dioxide into the light burned dolomite lime emulsion, and control the flow of carbon dioxide to 40-50L·h -1 , While stirring, the stirring speed is controlled to 150r / min, and the pH value of the reaction mixture is detected while the carbon dioxide is introduced. When the pH=6.89, the introduction of carbon dioxide is stopped, the calcium carbonate is removed from the filter residue, and the heavy magnesium aqueous solution is left. Calcium and magnesium are separated and removed most of the impurities and calcium ions for the first time;

[0027] 3) Take the heavy magnesium aqueous solution, add 40% of the absolute ethanol equivalent to the volume of the heavy magnesium aqueous solution, heat in a water bath and control the temperature of the water bath at 80℃ for 1 hour, and then ...

Example Embodiment

[0032] Example 2

[0033] 1) Pour 60g of lightly burned dolomite powder into 1 liter of water at 55°C and digest for 50 minutes to obtain lightly burnt dolomite lime emulsion;

[0034] 2) Pour carbon dioxide into the light burned dolomite lime emulsion, and control the flow of carbon dioxide to 70~80L·h -1 , While stirring, the stirring speed is controlled to 160r / min, and the pH value of the reaction mixture is detected while introducing carbon dioxide. When pH=6.94, stop introducing carbon dioxide, remove the filter residue calcium carbonate, and leave the heavy magnesium aqueous solution. Calcium and magnesium separate and remove most of the impurities and calcium ions for the first time.

[0035] 3) Take the heavy magnesium aqueous solution, add 30% of the absolute ethanol equivalent to the volume of the heavy magnesium aqueous solution, heat in a water bath and control the temperature of the water bath to 60℃ for pyrolysis for 1.5 hours, then filter to obtain solid magnesium bic...

Example Embodiment

[0040] Example 3

[0041] 1) Pour 60g of lightly burned dolomite powder into 1 liter of water at 65°C and digest for 45 minutes to obtain lightly burnt dolomite lime emulsion;

[0042] 2) Inject carbon dioxide into the light burned dolomite lime emulsion, and control the flow of carbon dioxide to 60~70L·h -1 , While stirring, the stirring speed is controlled to 150r / min, and the pH value of the reaction mixture is detected while the carbon dioxide is introduced. When the pH = 6.70, the introduction of carbon dioxide is stopped, the calcium carbonate is removed from the filter residue, and the heavy magnesium aqueous solution is left. Calcium and magnesium are separated and removed most of the impurities and calcium ions for the first time;

[0043] 3) Take the heavy magnesium aqueous solution, add 35% of the absolute ethanol equivalent to the volume of the heavy magnesium aqueous solution, heat it in a water bath and control the temperature of the water bath to 50℃ for 2 hours, and 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

PropertyMeasurementUnit
Diameteraaaaaaaaaa
Login to view more

Abstract

The invention discloses a method for preparing magnesium hydroxide utilizing light-burned dolomite powder. The method comprises the following steps: adding the light-burned dolomite powder to enough water for digestion; introducing a carbon dioxide gas to obtained light-burned dolomite emulsion until the pH value of the reaction product is 6.7-7.0, and filtering the product; adding absolute ethanol to filtrate, heating and controlling the temperature to 50-80 DEG C, and after reaction, filtering, wherein the amount of absolute ethanol is controlled to be 30-40% of the volume of the filtrate; adding hydrochloric acid to obtained solid magnesium bicarbonate until bubbles disappear; adding a base liquid to an obtained magnesium chloride solution; and adding polyvinylpyrrolidone or ethylenediamine to obtained magnesium hydroxide slurry, wherein the amount of polyvinylpyrrolidone or ethylenediamine is equal to 2-6% the volume of the slurry; and then adding the slurry into an autoclave, controlling the temperature at 80-200 DEG C and stirring under constant temperature condition for 10-20 hours. Magnesium hydroxide precipitate prepared by the method disclosed by the invention is in a fibrous or flaky crystal shape and has high purity; and the preparation method is simple to operate, and the reaction conditions are mild and easy to control.

Description

technical field [0001] The invention belongs to the technical field of inorganic material preparation, in particular to a method for preparing magnesium hydroxide by using lightly burned dolomite powder. Background technique [0002] Magnesium hydroxide has the properties of flame retardancy, smoke suppression, non-toxicity and high thermal decomposition temperature, and is widely used in polymer flame retardancy, wastewater treatment, flue gas desulfurization and other fields. However, when magnesium hydroxide is used as a filler-type inorganic flame retardant, a large amount of filler will make its dispersion in the polymer worse and reduce the mechanical properties of the composite material. Studies have shown that the modification of magnesium hydroxide and the control of particle size and morphology can improve this shortcoming. When the added magnesium hydroxide particle size is reduced to 1 μm, the oxygen index of the flame retardant polymer system is significantly in...

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): C01F5/14
Inventor 章启忠刘家祥饶发明勇昕伍朝蓬李敏季佳善
Owner WUHAN IRON & STEEL (GROUP) CORP
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