Preparation method for hexagonal sheet magnesium hydroxide

A technology of magnesium hydroxide and hexagonal flakes, applied in the direction of magnesium hydroxide, etc., can solve the problems of environmental pollution, inability to control the size and thickness of magnesium hydroxide particles, etc., and achieve low production costs, easy control of shape, and short time Effect

Active Publication Date: 2012-06-20
NANJING UNIV OF TECH
View PDF8 Cites 17 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

), but the above-mentioned work is mainly aimed at the influence of magnesium oxide hydration conditions on the particle size of magnesium hydroxide, and cannot control the size and thickness of the synthetic magnesium hydroxide particles, and the basic additives (such as sodium hydroxide, ammonia water) used in the above-mentioned research , urea) will cause certain pollution to the environment

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
  • Preparation method for hexagonal sheet magnesium hydroxide
  • Preparation method for hexagonal sheet magnesium hydroxide
  • Preparation method for hexagonal sheet magnesium hydroxide

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0024] Weigh 2 g of magnesium oxide obtained by calcination of magnesite at 600 ° C for 8 hours and pass through a 200 mesh sieve, add 0.6 g of magnesium sulfate and 50 ml of water into the aqueous solution, and mix well, control the temperature of the water bath at 40 ° C, and add 0.4 g magnesium hydroxide crystal seed, continue to react 23h under the condition of constant stirring, stop stirring; The Mg(OH) 2 Slurry is filtered, washed and dried to obtain hexagonal flaky magnesium hydroxide product. Generated Mg(OH) 2 Crystal XRD such as figure 1 as shown, figure 2 It is a scanning electron microscope photo of the product obtained in this example. It can be seen from the figure that the product is a hexagonal sheet with a diameter of about 500 nm, a uniform particle size distribution, and a thickness of about 20 nm.

Embodiment 2

[0026] Magnesite was calcined at 800°C for 6 hours, and passed through a 200-mesh sieve to obtain active magnesium oxide. Weighed 2g of the above-mentioned magnesium oxide and added it to an aqueous solution composed of 2g of magnesium sulfate and 100ml of water to obtain a uniformly mixed suspension of magnesium oxide. The reaction temperature was controlled to 60°C, react for 30min, add 0.2g magnesium hydroxide seed, continue to react for 4h under constant stirring, stop stirring; control crystal growth temperature 40°C, keep at this temperature for 24h, grow Mg(OH) 2 crystals, and finally, the resulting Mg(OH) 2 The slurry is filtered and dried to obtain the magnesium hydroxide product. The product is a regular hexagonal sheet with a particle size of about 200-300nm and a thickness of about 50nm.

Embodiment 3

[0028] Weigh 4g of magnesium oxide obtained by calcining magnesite at 950°C for 6h and passing through a 200-mesh sieve, add 8g of magnesium nitrate and 200ml of water into the aqueous solution, mix well, adjust the temperature of the water bath to 80°C, and add 0.1g of hydroxide after 10min of reaction Magnesium seed, continue to react for 40min under the condition of constant stirring, stop stirring; control crystal growth temperature 70 ℃, keep warm at this temperature for 48h, and the prepared Mg(OH) 2 The slurry is filtered, washed and dried to obtain powdery magnesium hydroxide. image 3 For the scanning electron microscope photo of this example, by image 3 It can be seen that the product is in the shape of hexagonal flakes, with a particle size of 100nm-200nm and a thickness of about 40nm.

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
particle diameteraaaaaaaaaa
thicknessaaaaaaaaaa
particle diameteraaaaaaaaaa
Login to view more

Abstract

The invention provides a preparation method for hexagonal sheet magnesium hydroxide, which includes the following steps: 1 roasting natural magnesite to obtain light-roasting magnesium oxide, 2 adding the light-roasting magnesium oxide to magnesium salt aqueous solution according to a certain proportion, 3 enabling the suspension prepared in step 2 to react for a certain period of time in constant-temperature water bath under the condition of mixing, 4 adding magnesium hydroxide seed crystal after a certain period of time of reaction in step 3, and standing the reaction product in the constant-temperature water bath, and 5 filtering, washing and drying the product of step 4 to obtain the hexagonal sheet magnesium hydroxide with regular shapes. The preparation method for the hexagonal sheet magnesium hydroxide has the advantages that raw materials can be easily obtained, a process is simple, a step of traditional hydration hydro-thermal treatment is removed, energy consumption is reduced, and the preparation method is suitable for industrial production and the like. Different sizes and thicknesses of hexagonal sheet magnesium hydroxide can be prepared by changing process conditions of magnesium salt type and concentration, hydration temperature and time, standing time and the like. The prepared magnesium hydroxide can serve as seed crystal to be recycled so that production cost is lowered.

Description

technical field [0001] The invention belongs to the technical field of inorganic chemical industry, and in particular relates to a preparation method for hydrating hexagonal flaky magnesium hydroxide by using light-burned activated magnesium oxide. Background technique [0002] With the development of the polymer material industry, polymer composite materials such as plastics, synthetic rubber, and synthetic fibers are more and more widely used in building materials, home appliances, electronic equipment, automobiles, chemicals, transportation and other fields. The flame retardant performance of polymer materials has also attracted worldwide attention. In recent years, with the increase in the number of major fires, the emergence of secondary pollution caused by polymer incineration and the emergence of dioxins (Dioxion) have aroused people's attention to environmental protection issues, making organic The application of brominated flame retardants is limited. Based on peo...

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): C01F5/14
Inventor 钱海燕王飞
Owner NANJING UNIV OF TECH
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