Atomically Dispersed Pd on Nanodiamond/Graphene Hybrid for Selective Hydrogenation of Acetylene

Highly Dispersed PdNPs/α-Al2O3 Catalyst for the Selective Hydrogenation of Acetylene Prepared with Monodispersed Pd Nanoparticles

Pd nanoparticles (PdNPs) stabilized by methyl cellulose (MC) were synthesized in an aqueous solution, which are monodispersed nanoparticles. PdNPs/α-Al2O3 catalyst was prepared with monodispersed PdNPs and showed better catalytic performance than Pd/α-Al2O3 catalyst prepared by the incipient wetness impregnation method using Pd(NO3)2 as a precursor. The catalysts were characterized by transmiss...

An Egg-Shell Pd-Ag/ α -Al 2 O 3 Catalyst for Tail-End Acetylene Selective Hydrogenation

TiO2 supported Pd@Ag as highly selective catalysts for hydrogenation of acetylene in excess ethylene.

A novel TiO2 supported core-shell (Pd@Ag) bimetallic catalyst was fabricated via the sequential photodeposition method. The Ag shell effectively blocks the high coordination sites on the Pd core, and therefore pronouncedly enhances the ethylene selectivity for the catalytic hydrogenation of acetylene in excess ethylene.

Improved selectivity by stabilizing and exposing active phases on supported Pd nanoparticles in acetylene-selective hydrogenation.

Palladium dynamics: Under hydrogenation conditions, saturating over-active palladium by carbon diffusion leads to a stable and selective particle surface. By choosing supports with suitable geometric structures and establishing a strong interaction between supports and metal particles, accumulated species can be regularly rearranged and reaction-selective phases can be exposed (see figure).

Selective Hydrogenation of Acetylene over Palladium in Ultra High Vacuum

Under ultra-high-vacuum conditions, precoverage of a palladium(ll1) surface with hydrogen does not affect either the kinetics or the extent of acetylene uptake at 175 K. The subsequent reactive behavior of the system is however radically altered. Benzene formation is strongly suppressed, the transformation of adsorbed acetylene to another species (@-phase) is enhanced, and the yield of ethylene...