Precipitated Silica from Sodium Silicate by CO2 on Fixed Bed Column

Abstract

The precipitated silica prepared by reaction of sodium silicate and gas CO2 on fixed bed column have been production successfully. In this study, silica from bagasse was extraction by sodium hydroxide 2N solution to produce sodium silicate solution. The sodium silicate solution was dilute by demineralize water to produce some concentration in the range of 0.33-0.98 %SiO2. Fixed bed column has a diameter of 7.5 cm with a height of 50 cm and a pH control apparatus. CO2 gas and sodium silicate liquid are both flowed from under of the column with a specified flow rate. The precipitate process was carried out on a fixed bed column with high of bed in the range of 10-30 cm. The effect of silica concentration and the high of the bed on the characterize of the precipitated silica product have been studied. The precipitated silica product characterized by XRF, XRD, SEM-EDX and BET. The quality of precipitated silica produced in the range concentration of 95-98 w% SiO2, surface area (BET) in the range of 46.1 – 58.8 m2/g.