Synthesis of novel Ag-modified Pd-supported mesoporous carbon nitride for selective hydrogenation of acetylene with an excellence ethylene selectivity

Novel nanocatalysts were developed for selective hydrogenation of acetylene to ethylene. The mesoporous carbon nitride (MCN) was synthesized and employed as catalyst support that was loaded by Pd active sites. Moreover, for the first time, the Pd loaded MCN nanocatalysts were modified by different Ag/Pd ratios (in the range of 0.5:1, 1:1, and 3:1) which could bring about great results in terms of the acetylene conversion and ethylene selectivity. The prepared Ag-Pd/MCN nanocatalysts were thoroughly characterized by FESEM, TEM, BET, FTIR, and XRD methods. The catalytic performance of the nanocatalysts was evaluated in temperature range of 40-200 degrees C. It was found that loading Pd over the MCN results in better performances compared to the commercial Pd/alpha - Alumina catalyst. Furthermore, modifying the Pd/MCN nanocatalysts by adding Ag led to significant performances with about 99.8% acetylene conversion. In addition, the ethylene selectivity of the sample prepared by using the optimum Ag/Pd ratio (1:1), reached 98.1% at 200 degrees C which is an excellent performance. The significant performance of the Ag-Pd/MCN (1:1) nanocatalyst in selective acetylene hydrogenation is attributed to the simultaneous roles of MCN catalyst support (with the surface area of 152 m(2)/g) and also the Ag modifiers which could modify the adsorption strength of the Pd active sites toward ethylene and accordingly enhance the ethylene selectivity.

Automated summary

A novel nanocatalyst was developed for selective hydrogenation of acetylene to ethylene, utilizing mesoporous carbon nitride as the catalyst support and modifying the Pd active sites with different Ag/Pd ratios. The modified nanocatalysts showed excellent performance in terms of acetylene conversion and ethylene selectivity, with the sample prepared using the optimal Ag/Pd ratio (1:1) achieving 98.1% ethylene selectivity at 200 degrees C.