Catalytic hydrogenation of tetrahydrophthalic anhydride

Catalytic hydrogenation reaction of tetrahydrophthalic anhydride(THPA) to h exahydrophthalic anhydride(HHPA) has been studied. The effects of temperatu re, pressure, time and solvent on catalytic reaction have also been investi gated. Raney Ni(T-1) has high activity towards hydrogenation of THPA to HHP A. The amount of HHPA formed constantly increases with increasing temperatu re in the experimental temperature range (70-100 degrees C). The experiment al results show that conversion of THPA and selectivity to HHPA reach 88% a nd 100%, respectively under the appropriate reaction conditions (T-1 Raney Ni: 7%, H-2 pressure: 4.5MPa, 45% DMF solution, reaction time 3.0h, tempera ture: 95 degrees C).