Study On Production Of Furfural By Three Kinds Of Metal Salts Catalytic Hydrolysis Of Corncob

This thesis made a research about the corncobs hydrolysis with three kinds of metal salts catalyst (ferric sulfate, ferric chloride, chromium chloride). The effects of reaction temperature, reaction time, catalyst concentration on the yield of furfural were investigated. The kinetics that furfural was prepared from corn cob and furfural hydrolysis again were analyzed.When ferric sulfate was used as the catalyst, the yield of furfural was first increased and then decreased with increasing temperature. Over time, the yield of furfural was first increased and then decreased. The yield of furfural was increased with increasing catalyst concentration. The optimum condition:temperature175℃, reaction time102min, the mass fraction of12%, furfural yield62.67%.When ferric chloride was used as the catalyst, the yield of furfural trend with increasing temperature was first increased and then remained constant. The yield of furfural was first increased and then remained constant with the extension of time. The yield of furfural was increased with increasing catalyst concentration. The optimum conditions:temperature158℃, reaction time60min, the mass fraction of10%, furfural yield20.25%.When chromium chloride was used as the catalyst, the yield of furfural with the increasing temperature and the extension of reaction time and the increasing catalyst concentration, showed a decreasing trend. The optimum conditions:reaction temperature140℃, reaction time30min, the mass fraction of2%, furfural yield30.13%.The dynamic that furfural was prepared from corncobs and furfural produced the side reaction was analyzed. The results showed that:without catalyst, the apparent activation energy of the hydrolysis process was Ea1=85.00kJ/mol; and the apparent activation energy of the side reaction was Ea2=100.01kJ/mol. When ferric sulfate was used as the catalyst, the apparent activation energy of the hydrolysis process was Ea1=51.38kJ/mol; the apparent activation energy of the side reaction was Ea2=72.42kJ/mol. When ferric chloride was used as the catalyst, the apparent activation energy of the hydrolysis process was Ea1=198.25kJ/mol; the apparent activation energy of the side reaction was Ea2=21.53kJ/mol. When ferric chloride was used as the catalyst,, the apparent activation energy of the side reaction was Ea2=85.87kJ/mol.