Synthesis of carbon-based solid acid and its catalytic activity for esterification

A carbon-based solid acid catalyst was synthesized using peach stones as raw material.The effects of carbonization temperature,sulfonated temperature and sulphonation time on activity of the catalyst were investigated using esterification between ethanol and acetic acid as the model reaction. Thermal stability and surface composition of the catalyst were measured by TG and SEM/EDS, respectively.The results showed that optimal catalytic activity was attained over the catalyst carbonized at 300 ℃ ,sulphonated at 98 ℃ for 4.5 h,with 2.1 mmol sulfonic groups on the surface of 1g catalyst. Acetic acid conversion of 70.84% was obtained under the reaction condition as follows:catalyst dosage= 2% of the total mass of ethanol and acetic acid,ethanol-to-acetic-acid mole ratio of 1.5= 1,reaction temperature 70 ℃ ,reaction time 5 h.