Study On Pd/CNTs Catalyst Application On Synthesis Of Cyclohexanecarboxylic Acid By Hydrogenation Of Benzoic Acid

Cyclohexanecarboxylic acid is a very important and excellent chemical or pharmaceutical intermediate ,is used to the synthesis of 1-Hydroxy cyclohexyl phenyl ketone and Praziquantel,and many of its derivatives are also key chemical and pharmaceutical intermediates, for instant, trans-4-isopropylcyclohexyl acid, cyclohexylmethyl carbamate .But from now on there are few reports on synthesis of compounds of this kind, and it is hard to gain them by simple methods.This thesis was determined to find out a way to synthesize cyclohexacarboxylic acid through the study on catalytical hydrogenation of benzoic acid , we also wanted to make researchs on a new catalyst, Pd/CNTs catalyst , tried to find out its charactistics on hydrogenation reactions. Firstly, we tried to investigate the solvent fit for the reaction.Water and Cyclohexanecarboxylic acid were investigated.So a lot of researchs on the hydrogenation of benzoic acid in water phase and Cyclohexanecarboxylic acid were made, comparing the Pd/CNTs catalyst with the catalyst Pd/C, by the different activity and selectivity in series of temperatures , hydrogen pressures, Benzoic contents,catalyst contents, and so on. We Investigated their effects on reaction time and reaction conversions. In.common way, we gained the optimal conditions on the hydrogenation reaction by, Pd/CNTs,in water phase .and we got its optimal condition by orthogonal test in cyclohexanecarboxylic acid as solvent, It is: benzoic acid as solvent cyclohexanecarboxylic acid(120g) ,1:1.5 (in mass);140℃ as reaction temperature; hydrogention pressure: l.8MPa; Pd/CNTs catalyst :3.00g.We made Pd/CNTs catalyst micro-structural characterization by TEM and SEM, in order to explain the reason that Pd /CNTs catalyst has good activity in the reaction.Moreover,in this dissertation, we briefly discussed the reaction mechanism and reaction kinetics.And lastly,we made study on the catalyst's recycle and reuse.In the end,we reached the result,it's that: Pd /CNTs catalyst has good catalytic ability and activity in this reaction.