Method for preparing liquid sodium silicate by one-step liquid phase reaction

Abstract

The invention discloses a method for preparing liquid sodium silicate by one-step liquid phase reaction. Quartz sand and liquid alkali are mixed with 2.2-3.4:1 of SiO2: NaOH molar ratio and the mixture under stirring status is pumped into a liquid phase reaction pot which is in stirring status; steam is directly fed to heat and when the pressure in the pot reaches to 0.65MPa, steam is stopped feeding; the temperature is automatically raised to 0.65-0.75MPa, and after 4-6 hours of full reaction, decompression and vacuum drawing and filtering are carried out, and the liquid material drawn and filtered is liquid sodium silicate with high purity. The invention also discloses a liquid phase reaction pot which is used specially in the method. The method of the invention has short synthesis line, few control points and simple operation, can obtain liquid sodium silicate products with high quality, generates no three wastes during the whole production course and pertains to green chemical production technique.

Description

technical field [0001] The invention relates to a method for preparing liquid sodium silicate, in particular to a method for preparing liquid sodium silicate by using liquid phase reaction. Background technique [0002] The traditional sodium silicate production process is to put quartz sand and soda ash into a special high-temperature roasting furnace, heat and melt with coal or oil, discharge the material after the reaction is sufficient, and rinse and quench the material directly with cold water to form a glassy sodium silicate solid. blocks. Then use the melting drum to pressurize the block with water and a certain amount of liquid caustic soda to 0.6-0.7Mpa and melt it into a liquid sodium silicate product. There are a number of problems with this approach: [0003] 1. The content of silicon dioxide in quartz placer is generally 95-97%, containing a large amount of metal ions such as iron, calcium, magnesium, aluminum, etc. After high-temperature roasting, these ions ...

AI Technical Summary

Problems solved by technology

[0003] 1. The content of silicon dioxide in quartz placer is generally 95-97%, containing a large amount of metal ions such as iron, calcium, magnesium, aluminum, etc. After high-temperature roasting, these ions form semi-melting polymer substances with sodium silicate , so that it cannot be effectively separated from the finished product, and the latter product contains a large amount of impurities

The melted sodium silicate can only be used as carton adhesive or ceramic dispersant for industrial use that does not require high impurities, and cannot be used as a further chemical synthesis product

[0004] 2. To make liquid sodium silicate, the block from the roasting furnace must be subjected to high-pressure reaction of adding alkali and water. The process is long and consumes a lot of energy, which is not conducive to the national industrial policy

[0005] 3. Can only produce relatively single products

In actual use, an additional set of equipment must be added for adjustment

[0006] 4. The roasting furnace and high-pressure drum equipment require a large investment and occupy a large area. They are non-standard equipment and are not easy to control

[0007] 5. The batch difference in product quality is large, which is not conducive to industrial production control

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