Carbon-supported palladium-ruthenium catalyst for hydropurification of terephthalic acid

dThe ruthenium-incorporated catalyst, (0.3% Pd-0.2% Ru)/CCM (carbon carbonaceous composite material) catalyst, has been studied as a candidate to replace an existing 0.5% Pd/C catalyst for hydropurification of crude terephthalic acid; it gives an excellent performance and is a promising catalyst. It has been confirmed that the (0.3% Pd-0.2% Ru)/CCM catalyst has higher stability in actual commercial condition and aging in lab condition compared with a commercial catalyst. The increased stability may be explained as the effect of ruthenium to prevent the sintering of supported metal particles. The (0.3% Pd-0.2% Ru)/CCM catalyst shows equal or less amount of side reaction of benzene ring hydrogenation. The dust from carbon support can also be decreased from the (0.3% Pd-0.2% Ru)/CCM catalyst due to the increased strength of the CCM. The (0.3% Pd-0.2% Ru)/CCM catalyst may be very competitive to the existing catalyst due to the inexpensive ruthenium and the expected long life of the catalyst. (C) 2002 Elsevier Science B.V. All rights reserved.