Properties: Colorless translucent crystal or white crystal powder. Tasteless and salty. Specific gravity 1.73. 320 & ampordmc lost all crystal water. Soluble in water and glycerol, slightly soluble in alcohol. The aqueous solution is weakly alkaline. Borax can be weathered slowly in the air. After melting, it becomes a colorless glassy substance. Borax has bactericidal effect, and oral administration is harmful to people.
Uses: Mainly used in glass and enamel industry. In glass, the ultraviolet transmittance can be enhanced, and the transparency and heat resistance of glass can be improved. In enamel products, it can make enamel not easy to fall off and shiny. Special optical glass, glass fiber and non-ferrous metal welding agent.
Jewelry adhesive, printing and dyeing, washing (silk and woolen goods, etc. ), gold refining, cosmetics, pesticides, fertilizers, borax soap, preservatives, antifreeze, medical disinfectants, etc. are also widely used. Borax is the basic raw material for preparing boron-containing compounds, and almost all boron-containing compounds can be prepared with borax. They are widely used in metallurgy, steel, machinery, military industry, cutting tools, paper making, electron tubes, chemicals and textiles.
Manufacturing method and process flow
1. Pressurized alkaline hydrolysis: the pretreated boron-magnesium ore powder is mixed with sodium hydroxide solution, heated and pressurized to decompose to obtain sodium metaborate solution, and then carbonized to obtain borax.
2MgO。 B2 O3+2 NaOH+H2O→2 nabo 2+2mg(OH)2·4 nabo 2+CO2→na 2 B4 o 7+na2co 3
2. Carbonization-alkali method: the pretreated boron-magnesium mineral powder and sodium carbonate solution are mixed and heated, and the borax is obtained after the pressure is increased by introducing carbon dioxide.
2(2MgO。 B2 O3)+na2co 3+2co 2+xH2O→na 2 B4 o 7+4m go . 3 CO2 . xH2O
3. Alkaline hydrolysis of soda ash (well salt brine): the well salt brine is treated to obtain borax paste, which is mixed with soda ash and cooked to obtain borax.
CaB4O7+ Na2CO3→Na2B4O7+ CaCO3
4H3BO3+ Na2CO3→Na2B4O7+6H2O+CO2
4. Alkaline hydrolysis of soda ash (ulexite): The pretreated ulexite is decomposed with soda ash and baking soda, and then precipitated and crystallized with causticized starch to obtain borax.
2(nao . 2 Cao . 5b2o 3 . 16H2O)+na2co 3+nah co 3→5 na 2 B4 o 7+4c ACO 3+CO2+34H2O
Packing: packed in gunny bags, lined with two layers of kraft paper or plastic bags. The net weight of each bag is 40 kg, 50 kg or 80 kg.
Precautions for storage and transportation: boxcars, carriages or cars with sheds should be used for transportation, and they should not be mixed with wet materials or other colored materials. The means of transport must be dry and clean. Store in a dry and clean warehouse to avoid rain or moisture. Fire can be put out with water, sand and carbon dioxide fire extinguishers. Usage: This product can be used to manufacture various boron compounds, such as elemental boron, borate, metaborate, metallic boron compounds, organic boron compounds, etc. In the glass industry, it is used to manufacture special glass and glass fiber, such as optical glass, heat-resistant high-strength glass, glass-ceramics, etc., in order to enhance ultraviolet light transmittance and improve glass transparency. In enamel and ceramic products, borax can make the surface smooth and the enamel is not easy to fall off. In metallurgical industry, it is used to produce high-strength boron steel, high-hardness heat-resistant alloy steel and special steel with acid corrosion resistance, as well as deoxidizer, cosolvent and purifying agent for nonferrous metal smelting; Used for surface boronizing in mechanical industry to improve hardness and metal welding; Used for boron doping, capacitors, etc. In the electronics industry; It can be used as trace element fertilizer and pesticide in agriculture; In the fine chemical industry, it is an indispensable ingredient in the production of detergents, adhesives, cosmetics and so on.
Test item [test item] technical index [technical index]
Superior product [best quality] first-class product [first-class product]
Main contents (Na2B4O7? 10H2O) ≥% 99.5 95.0
Carbonate (calculated as CO2) content ≤% 0. 1 0.2
Water insoluble matter content ≤% 0.04-0.04
Sulfate content (calculated as SO4) ≤% 0. 1.2
Chloride (calculated as Cl) content ≤% 0.03 0.05
Iron content ≤% 0.002-0.005