Abstract:Nano porous material SiO2 were prepared by acid-alkali two steps approach with low cost industrial silica sol as silicon source and deionized water as solvent. The surfactant was used as the surface modifier to get rid of the broken of samples in the drying process. The densities, specific surface area and the average pore size of the obtained SiO2 monoliths are in the range of 150~400 mg/cm3 and the range of 0.04~0.07W/(m.K), respectively. This method greatly reduced the cost in the preparation of SiO2 nano porous material, which will largely promote the industrial production and application of porous SiO2 materials.