Effects of Precipitation and Drying Processes on the Synthesis of Silica Materials with a Large-Pore-Volume and Narrow-Pore-Diameter Distribution

In this paper, a novel process using the combination of a microreactor and a stirred-tank reactor for the controlled preparation of silica materials with a large-pore volume and narrow-pore-diameter: distribution was presented. At the precipitation stage, the gelation time was controlled to within 50 ms by improving the mixing performance in the mieroreactor. After further mixing and acidizing in a stirred-tank reactor, Silica with a pore volume of 1.96 mL/g and a specific surface area of 476.1 m(2)/g was prepared. The primary particle size was 10 Pm, and the variance of the logarithmic pore diameter was approximately 0.20, which indicated that the pore-diameter distribution was narrow and uniform particles were in favor of accumulating uniform pores. At the drying stage, with the addition of poly(vinyl alcohol) to a silica slurry, the process conditions were optimized, and silica with a larger pore volume of 2.13 mL/g was prepared.