calculation method for specific surface area of microsilica-pg电玩城

microsilica is a kind of environmental protection equipment made of nanometer materials. the color of microsilica is determined by raw materials and production process. as the fineness of silica powder is less than 1um, accounting for more than 80%, the average particle size is between 0.1 and 0.3um, and the specific surface area is between 20 and 28m2/g. its fineness and specific surface area are about 80 ~ 100 times of cement and 50 ~ 70 times of fly ash.

what's the relation between the specific surface area and fineness of the microsilica?

1. fineness refers to the degree of thickness of powdery raw materials, which is usually expressed by the percentage of standard screen or specific surface area, or by the percentage of particle size or the average value of materials per unit weight. there is no strict difference between fineness and particle, but the former is used to fine powdery raw material degree of thickness.

2. specific surface area refers to the surface area per unit weight of raw materials, which is m2/g. specific surface area is divided into external specific surface area and internal specific surface area. the ideal non-porous material has only external specific surface area. however, the raw materials with pores are subject to internal specific surface area in addition to comparative surface area. there are many methods for measuring specific surface area, such as gas adsorption, organic molecule adsorption and air permeability.

calculation method of specific surface area of microsilica:

transmission electron microscopy can be used to easily measure the particle size of the silica fume sample. the scale length is 100nm. it can be seen that the particle size of the microsilica sample is between 10-100nm with an average particle size of 30-40nm. take 40nm as an example:

1. volume of single grain silica powder: v=4/3 * time * (40 * 10-9)3=2.68 * 10-22m3

2. the surface area of the single silica powder is s=4 seconds * (40 * 10-9)2=2.01 * 10-14m2

3. the apparent proportion of silicon powder is calculated as 2600kg/m3, and the number of silicon powder particles per kg is: 1/2600 2.68x10-22 = 1.44x1018 grains.

therefore, the surface area of silicon powder per kg is: 1.44 * 1018 * 2.01 * 10-14= 29,000 m2