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

•Mesoporous silica-based solid acid was synthesized in the absence of template.•High surface silicon exposure supplied large amount of surface groups to be available.•Acetaldehyde was removed (above 99.99 %) from ethanol through a novel strategy of “waste to value”.•The remaining acetaldehyde was controlled to be below 0.01 ppm with a wide range of concentration.