Vapor-phase Nitration of Benzene to Nitrobenzene over Supported Sulfuric Acid Catalyst

Vapor-phase nitration of benzene over solid acid catalyst is expected to be a clean process with no sulfuric acid waste.We investigated this process over solid acidic catalysts utilizing diluted nitric acid (60-70%) as nitrating agent,and found that supported sulfuric acid catalyst exhibited a very high catalytic activity.Under the conditions of reaction temperature 160-170℃,space velocity (SV) 1200 h-1,the yield and the space-time yield (STY) of nitrobenzene (NB) based on HNO3 were more than 98% and 0.75 kg@kgcat-1@h-1 over 10% H2SO4/SiO2 (by weight) catalyst respectively.