Efficient removal of acetaldehyde from ethanol by template-free synthesized mesoporous SiO2-based solid acid catalyst with high surface silicon exposure

Abstract

In the absence of any template, mesoporous silica-based solid acid owing a high surface area (380.2 m2/g), big average pore size (5.6 nm), and moderate acid amount (1.33 mmol/g) was synthesized through a one-step reverse-phase microemulsion method. The introduction of 3-sulfopropyl as the acidic sites by this method increased the surface silicon exposure to a high value of 74.1 %, which enabled plenty of active groups to be available on the surface. As the main impurity in ethanol and has the potential to cause the serious damage for people’s health, acetaldehyde was removed with high removal (above 99.99 %) from ethanol through a novel strategy of “waste to value” with the present acid catalyst at the ambient temperature, in which acetaldehyde was converted to a much safer chemical of acetal that owns a pleasant odor and is permitted to be used as the fragrance in food. The remaining acetaldehyde could be controlled to a very low and much safer level of below 0.01 ppm with a wide range of initial concentration.