Hydrogenation of acetylenic contaminants over Ni-Based catalyst: Enhanced performance by addition of silver

The hydrogenation of acetylenic contaminates into valuable chemicals is a clean and promising process for minimizing the waste and improving economic benefits. In this work, the enhancement of Ag on Nil Al2O3 catalyst for acetylenic stream hydrogenation was studied by multiple characterization techniques and DFT calculations. The addition of Ag shows negligible effect on the particle size of Ni nanoparticles, but modifies the electronic and geometric structures of Ni active sites by electron transfer and site isolation, respectively, which weaken the adsorption strength of Ni sites for reactants and intermediates and thus suppress their polymerization. Due to the enhancement of Ag, Ni-Ag/Al2O3 catalyst exhibited excellent performance for the hydrogenation of acetylenic contaminates for a 700-h evaluation: similar to 99.8% of total conversion and similar to 98% of butane selectivity. Moreover, besides the high-quality products of butane, the results of simulation by Aspen Plus simulator indicates that 98% of benzene in acetylenic contaminates can be recovered as a chemical product with 99% of purity. This Ni-Ag/Al2O3 catalyzed hydrogenation process for acetylenic contaminates exhibits a potential of substantial economic and green benefits for the industrial production. (C) 2019 Elsevier Ltd. All rights reserved.