Preparation And Characterization Of Thermoregulated Catalyst And Study On Solvent Free Catalytic Oxidation Of Toluene

The oxidation of toluene is an important chemical reaction.Benzoic acid,benzaldehyde,benzyl alcohol are commonly used in medicine,food,and other industries.At present,the production process is mainly using toluene liquid phase catalytic oxidation.At home and abroad is mainly used as cobalt salt,cobalt acetate as catalyst,but the oxidation products of decarboxylation product serious,benzoic acid,benzaldehyde and benzyl alcohol selectivity is relatively low,the catalyst node faults,scaling,serious loss etc.Therefore,is of great significance to develop new catalysts.The "green" Lewis acid transition metal catalyst was synthesized,characterized by FT-IR,elemental analysis,solubility,TG.The crystal structure was characterized by single crystal diffraction.The analysis shows that the three catalysts are thermoregulator catalysts,and the catalysts are dissolved in water above 58? and precipitated at 48?.The oxidation of toluene was made in the condition of solvent free and no initiator.The results showed that the three catalysts showed well catalytic activity for the oxidation of toluene,of which the activity of cobalt was the highest.In the presence of solvent free and no initiator,the oxidation of toluene catalyzed by catalyst Co was studied.The best reaction conditions were as follows: the dosage of toluene and catalyst is 10 g and 0.1816g(0.3% of toluene molar mass),the temperature is 150?,the oxygen pressure is 1.2 MPa,the reaction time is 3h.Under this condition,the conversion of toluene is 11.16%,the selectivity of benzaldehyde is 13.24%,the selectivity of benzyl alcohol is 12.78%,and the selectivity of benzoic acid is 71.45%.After the reaction,the extraction and separation can be performed directly.After many stability experiments,it is found that the experiment has a good reproducibility.In the presence of solvent free and no initiator,the oxidation of toluene catalyzed by NHPI(N-Hydroxyphthalimide)/Co was studied.The best reaction conditions were as follows: the dosage of toluene and catalyst is 10 g and 0.4% of toluene molar mass,the ratio of Co/NHPIis 1:1,the reaction temperature is 150 ?,the oxygen pressure is 1 MPa,the reaction time is 2h.The average conversion of toluene can reach 24.89%,and the selective average of benzoic acid can reach 95.23%.