Particle Size Effects in the Selective Hydrogenation of Alkadienes over Supported Cu Nanoparticles

Abstract

Copper is considered an excellent alternative to noble‐metal selective hydrogenation catalysts. Herein, we systematically studied the effect of Cu nanoparticle size (2–10 nm) in the selective hydrogenation of 1,3‐butadiene in excess of propene. The catalysts exhibited particle size‐dependent activity, with particles above 4 nm being 3 to 4 times more active than the 2 nm ones, and at the same time more selective (up to 99 % at almost full butadiene conversion for 7–10 nm particles). The higher activity of larger particles was ascribed to a higher fraction of kinks and step sites, essential to activate hydrogen. The high selectivity of nanoparticulate Cu catalysts was explained by a very strong preferential adsorption of 1,3‐butadiene compared to mono‐olefin adsorption on the Cu surface (in particular on larger particles), as proven via adsorption measurements. These findings may guide both testing and catalyst design for reactions where hydrogen surface availability and selectivity play a key role.

Mass transport effects in gas-phase selective hydrogenation of 1,3-butadiene over supported Pd

“…An increasing trend in size was observed with decreasing weight loading, contrary to expected loading-size correlations, where higher metal loadings typically result in more agglomeration and thus larger particles. 57–60 The observed trend in particle size might be attributed to a slight instability of the diluted Pd-precursor, as the catalysts were prepared from high to low weight loading in successive order (see section 2.2), although more a more detailed study into the catalyst synthesis mechanism would be required to confirm this interpretation. Regardless of the slight trend, the nanoparticles in the different catalysts were of a suitable size (>4 nm), so minimal effects due to size-dependent catalytic performance are present.…”

InNi3C0.5@C-derived InNi3 alloy as a coke-resistant low-temperature catalyst for selective butadiene hydrogenation

“…On the other hand, replacing precious metal catalysts with cheap candidates is attractive in heterogeneous catalysis. For BD hydrogenation, distinct catalytic systems based on cheap transition metals have been reported in the last decade, including Cu, [15][16][17][18] Ni, [19][20][21] Fe, 22 Co, 23,24 and Mo. 25,26 Nonetheless, catalyst deactivation owing to the deposition of carbonaceous materials is frequently reported in the literature (Cu, 17,18 Ni, 20 Fe, 22 Co, 23,24 Mo (ref.…”

“…For BD hydrogenation, distinct catalytic systems based on cheap transition metals have been reported in the last decade, including Cu, [15][16][17][18] Ni, [19][20][21] Fe, 22 Co, 23,24 and Mo. 25,26 Nonetheless, catalyst deactivation owing to the deposition of carbonaceous materials is frequently reported in the literature (Cu, 17,18 Ni, 20 Fe, 22 Co, 23,24 Mo (ref. 25 and 26)), causing a drop in activity and alteration in the product distributions.…”

Palladium particle-catalyzed selective butadiene hydrogenation: effect of covalent organic framework modification

“…Considering the scarcity of precious metals, developing non-precious metal-based catalysts is attracting much attention in BD hydrogenation. In this regard, distinct catalysts based on Cu, [27][28][29][30] Ni, [31][32][33] Fe, 34 Co, 35,36 and Mo (ref. 37 and 38) have been reported in the last decade.…”