1, the introduction
The main component of silica is SiO2, which is named because it is white and its main physical properties and uses are similar to those of carbon black.
Silica can be divided into precipitated silica (precipitated hydrated silica) and fumed silica (fumed silica) according to different production methods. The production methods of the two products are different, and the properties and uses are also very different. The products described below are produced by a sulfuric acid precipitation method, that is, a precipitated white carbon black, and the following white carbon blacks are all precipitated white carbon blacks.

2, the name definition and molecular formula
The scientific name of white carbon black: precipitated hydrated silica.
Definition: Precipitated hydrated silica is a material composed of amorphous particles obtained by precipitation from a soluble silicate water-sinking solution.
Chemical formula: SiO2·nH2O
Third, the main nature
1, physical properties
Appearance: white powder or granular or irregular agglomerates.
True density: about 2.0 g/ml. False density: about 0.2 g/ml (common product).
High temperature resistance, no burning; good electrical insulation.
2. Chemical properties:
Can react with caustic soda SiO2nH2O+2NaOH=Na2SiO3+(n+1)H2O
Can react with hydrofluoric acid SiO2nH2O+4HF=SiF4+(n+2)H2O
2. Main chemical indicators
SiO2 content (dry product) ≥90%
Sieve residue (4.5цm) ≤ 0.5%
Heating loss: 4.0-8.0%
Burning reduction: (dry) ≤7.0%
PH value: 5.0-8.0
Total copper content: ≤30mg/kg
Total manganese content: ≤50mg/kg
Total iron content: ≤1000mg/kg
DBP absorption value: 2.00-3.50cm3/g
Specific surface area: different uses have different ranges, our product control
145-165m2/g(HT2#) 165-185m2/g(HT1#)
200-300m2/g(HT3#)

3, the main physical properties (with rubber products)
Tensile strength ≥17.0Mpa 500% tensile strength ≥6.3Mpa
Break elongation ≥675%

4, the production principle
Water glass and sulfuric acid react to form hydrated silicic acid
   heating
Na2O·mSiO2+H2SO4+nH2o-→Na2SO4+mSiO2·(n+1)H2O↓
The reaction completion liquid is dehydrated by pressure filtration, washed, and obtained by slurrying to obtain a white carbon black slurry, which is spray-dried to obtain a white carbon black finished product.

5, the main purpose
Since its industrial production in the 1940s, white carbon black products have been widely used in various industries for more than 60 years. In addition to being widely used as a reinforcing agent in rubber products, it can also be used in the pharmaceutical industry. , pesticides, inks, paints, coatings, toothpaste, paper, food, feed, cosmetics, batteries and other industries.