The effects of bimetallic interactions for CO₂‐assisted oxidative dehydrogenation and dry reforming of propane

Abstract

The catalytic reduction of CO 2 by propane may occur via dry reforming to produce syngas (CO + H 2 ) or oxidative dehydrogenation to yield propylene. Utilizing propane and CO 2 as coreactants presents several advantages over conventional methane dry reforming or direct propane dehydrogenation, including lower operating temperatures and less coke formation. Thus, it is of great interest to identify catalytic systems that can either effectively break the C C bond to generate syngas or selectively break C H bonds to produce propylene. In this study, several precious and nonprecious bimetallic catalysts supported on reducible CeO 2 were investigated using flow reactor studies at 823 K to identify selective catalysts for CO 2 -assisted reforming and dehydrogenation of propane. K E Y W O R D SCeO 2 , CO 2 soft oxidant, propane, propylene, synthesis gas | INTRODUCTIONCarbon dioxide management is a prominent issue facing society that requires a diverse portfolio of innovative technologies. High atmospheric concentrations of CO 2 contribute to adverse effects that impact human health and the climate. The need to reduce CO 2 is evident, and the International Panel on Climate Change has stated that climate stabilization (no more than a 2 C rise from preindustrial levels) will require a combination of mitigation, utilization, and even negative emission technologies. 1 Thus, one key approach will be to transform abundant CO 2 into a useful feedstock for processes that not only produce high value products but also match the scale necessary to impact anthropogenic emissions.The two most relevant reactions for the catalytic conversion of CO 2 to CO are reverse water gas shift (RWGS) and dry reforming of methane (DRM). The CO product can be utilized as feedstock for Fischer-Tropsch reactions or methanol synthesis. These two reduction chemistries are not without obstacles, beginning with the challenge that CO 2 is the most thermodynamically stable carbon/oxygen-based molecule (ΔG F = −394 kJ mol −1 ). 2 Current implementation of RWGS has limited feasibility since efforts to obtain large amounts of renewable and CO 2 -free hydrogen are still under development. 3 Furthermore, high coke deposition rates at the reaction temperatures required for DRM hinders further significant improvements in catalyst stability. 4,5 A viable alternative is to utilize other light hydrocarbons, such as ethane or propane, as feedstock for CO 2 reduction. In addition to reforming, these light alkanes contain the C C bond that can be advantageously utilized to build olefins. 6 Thus, the reduction of CO 2 via light alkanes offers two distinct reaction pathways: dry reforming and oxidative dehydrogenation. Specifically, it is of interest to explore the use of propane due to its increasing abundance, competitive pricing, and the demand for propylene, which is one of the most diverse petrochemical building blocks used in the production of various chemicals such as fibers and textiles for a variety of applications.Currently, propylene is primarily coproduced by...

A Novel Method of 3D Printing High‐Loaded Oxide/H‐ZSM‐5 Catalyst Monoliths for Carbon Dioxide Reduction in Tandem with Propane Dehydrogenation

“…To address these issues, other soft oxidants, such as nitrous oxide and carbon dioxide, have been considered as co‐feeds in propane dehydrogenation reaction. [ 5,6 ] The utilization of CO 2 as a soft oxidant does not form an explosive reactive mixture (unlike oxygen), prevents over oxidation of propylene and propane, and alters the pathway by providing an oxygen atom that combines with the hydrogen atoms from the propane CH bond scission to give water. This makes the reaction feasible at a lower operating temperature, due to its favorable thermodynamics compared to direct dehydrogenation of propane.…”

Butane Dry Reforming Catalyzed by Cobalt Oxide Supported on Ti2AlC MAX Phase

“…Butane, which is a side product of crude oil cracking and is widely available from shale gas, [9] is thermodynamically less stable (Δ G 0 =−16.6 kJ ⋅ mol −1 ) than smaller hydrocarbons such as methane (Δ G 0 =−50.5 kJ ⋅ mol −1 ). Therefore, dry reforming of butane (DRB) allows us to bring down the reaction temperature to 500–600 °C [10–13] . The problem is that dry reforming catalysts usually suffer from deactivation through sintering of active sites and coking [14] .…”

Effect of Oxide Support on Catalytic Performance of FeNi‐based Catalysts for CO2‐assisted Oxidative Dehydrogenation of Ethane

“…ZrO 2 is debatably considered to be reducible or at least partially reducible, but it is certain that the support exhibits surface defects or kinks that can strongly influence catalyst activity and selectivity [29]. CeO 2 is classified as a readily reducible oxide with ability to store and release oxygen, which not only facilitates CO 2 activation, but also provides lattice oxygen for coke suppression [30]. There is a clear need to expand the knowledge regarding the effect of oxide supports for the reaction of C 2 H 6 with CO 2 to develop highly active and selective catalysts for the This article is protected by copyright.…”