Efficient catalytic dehydrogenation of dodecahydro-N-ethylcarbazole over PDA-modified Al2O3-loaded PdCo bimetallic catalysts

Co/PDA-Al 2 O 3 precursors were prepared via a NaBH 4 reduction process with polydopamine-modified alumina (PDA-Al 2 O 3 ) as the carrier. Co 4 Pd/PDA-Al 2 O 3 catalysts were prepared via the galvanic replacement reaction (GRR) method with Co/PDA-Al 2 O 3 as the template and reducing agent. The above-prepared catalysts were analyzed for composition, structure, and morphology. The abundant N and O groups on the PDA-Al 2 O 3 surface anchored Co NPs, which promoted the uniform distribution of PdCo NPs with an average particle size of 2.92 nm. Ultrafine PdCo NPs and the coordination and strain effects between Pd and Co enhanced the catalytic performance of dodecahydro-N-ethylcarbazole (12H-NEC) dehydrogenation. The dehydrogenation efficiency of 12H-NEC catalyzed by Co 4 Pd/PDA-Al 2 O 3 achieved 100% at 180 °C for 4 h, and 98.45% at 170 °C for 6 h. The catalytic performance of 12H-NEC continuous dehydrogenation was evaluated in the fixed-bed reactor using Co 4 Pd/PDA-Al 2 O 3 as catalyst. The dehydrogenation efficiency was maintained at 95.4% for 100 h, indicating the excellent stability.