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

The 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.