Acetylene selective hydrogenation: a technical review on catalytic aspects

Abstract

<jats:title>Abstract</jats:title><jats:p>The catalytic selective hydrogenation of multiunsaturated hydrocarbons, especially in pyrolysis products, to corresponding mono-olefins is a widely exploited way for the large-scale production of polymer-grade olefins as well as fuel upgrading. Thermodynamic and/or kinetic parameters could be effective for selective operation. The latter is primarily influenced by catalyst formulation, including promoters, support type, and metal dispersion and distribution. The solution to achieve an economically attractive commercial implementation lies in defining the optimal catalyst design and operating conditions. The theoretical and practical aspects of catalysis for the selective hydrogenation of acetylene to ethylene are reviewed and the potential new ways to improve catalyst formulation are examined.</jats:p>

Pd/MCM-41 catalyst for acetylene hydrogenation to ethylene

“…The average particle size of the 1% Pd/SiO 2 catalyst was 5.04 nm with significant agglomeration. The high dispersion of metal Pd could inhibit the formation of the β-PdH phase because it promotes more ethane formation [24,25]. Thus, a large particle size and agglomeration of metal particles in Pd/Al 2 O 3 and Pd/SiO 2 catalysts make them less selective for ethylene.…”

Hydroxyl improving the activity, selectivity and stability of supported Ni single atoms for selective semi-hydrogenation

“…Raw ethylene generated by catalytic cracking generally contains 1% acetylene, which has to be removed or reduced to a few ppm to avoid downstream catalyst poisoning and the degradation of polyethylene quality during ethylene polymerization. [1][2][3][4][5] The selective hydrogenation of trace acetylene toward ethylene is the most widely used route in the removal of acetylene from the ethylene feed. The major side reaction in acetylene hydrogenation is the generation of undesirable ethane by ethylene hydrogenation and the coupling of C 2 species to a green oil blocking the active site.…”

Unraveling the Role of Site Isolation and Support for Semihydrogenation of Phenylacetylene

“…To get an insight into the role of the catalyst for semihydrogenation of phenylacetylene we need to have a better understanding of its mechanism. It is usually accepted that there are two main adsorption modes possible for acetylene on Pd surface as proposed by Ravanchi et al, one is associative and the other is dissociative . This can be extended for phenylacetylene as well.…”