Sorption-Enhanced Steam Reforming of Ethanol on a Novel K–Ni–Cu–Hydrotalcite Hybrid Material

Abstract

A multifunctional K−Ni−Cu−hydrotalcite hybrid material was synthesized for hydrogen production via sorptionenhanced steam reforming of ethanol. The hydrotalcite material was used as support for the incorporation of nickel and copper, both used as active catalytic phases. This material was studied for its catalytic properties for steam reforming of ethanol; it was found that Cu preferentially catalyzes ethanol dehydrogenation and water−gas shift reactions, while Ni is more suitable for acetaldehyde decomposition and steam reforming of methane. It was found that Ni and Cu formed a Ni 0.5 Cu 0.5 alloy with the advantage of ensemble formation. Also, promising carbon dioxide adsorption capacity of the material was obtained. The potassium promoter together with the hydrotalcite material for carbon dioxide adsorption ensured a successful sorptionenhanced reaction process. High-purity hydrogen stream (99.8 mol % on dry basis) was obtained during the prebreakthrough period at 773 K with a water-to-ethanol molar ratio of 10 in the feed; the concentration of hydrogen then decreased to 67.1 mol % after the breakthrough period.

Process Simulation for the Design and Scale Up of Heterogeneous Catalytic Process: Kinetic Modelling Issues

“…requires it. Without going into the details of this wider research field, we briefly account for at least three interesting aspects: (i) the intrinsic mass and heat transfer limitations of wall-coated microchannel reactors [56][57][58]; (ii) the time on stream-dependent kinetics due to the (relatively) slow and selective adsorption/release of a species [59,60]; (iii) the former phenomenon described in nonideal reactors characterized by temperature as well as pressure gradients [61,62]. We conclude this section on the experimental kinetics addressing also a couple of studies on the oxidative reforming of ethanol.…”

Coke Minimization during Conversion of Biogas to Syngas by Bimetallic Tungsten–Nickel Incorporated Mesoporous Alumina Synthesized by the One-Pot Route

“…As it was reported in the literature, stabilization of catalytic performances of Ni based catalysts for reforming and methane decomposition reactions could also be achieved by Cu addition into the catalyst structure. 4,8 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 9 Another important improvement achieved by tungsten incorporation was the approach of CO 2 and CH 4 fractional conversion values to each other. Due to the contribution of reverse water gas shift reaction (Eq.…”

“…[17][18][19][20][21][22][23][24] Ni and Cu based catalysts were considered as promising catalysts for both steam and dry reforming reactions. While Ni catalyzes reforming, Cu is reported to catalyze water gas shift reaction 4 . Due to their high activity, availability and low cost, Ni based catalysts attracted major attention of researchers.…”

Kinetic Modelling at the Basis of Process Simulation for Heterogeneous Catalytic Process Design

“…The correct modeling of these latter kinetics requires the implementation of PDE systems for every mass transport mechanism and possible heat transfers, if the foreseen system requires it. Without going into the details of this wider research field, we briefly account for at least three interesting aspects: i) the intrinsic mass and heat transfer limitations of wall-coated microchannel reactors [48][49][50]; ii) the time on stream-dependent kinetics due to the (relatively) slow and selective adsorption/release of a species [51,52]; iii) the former phenomenon described in nonideal reactors characterised by temperature as well as pressure gradients [53,54].…”