Highly efficient Ni/CeO2-Al2O3 catalysts for CO2 upgrading via reverse water-gas shift: Effect of selected transition metal promoters

Abstract

In the context of Carbon Capture and Utilisation (CCU), the catalytic reduction of CO 2 to CO via reverse watergas shift (RWGS) reaction is a desirable route for CO 2 valorisation. Herein, we have developed highly effective Ni-based catalysts for this reaction. Our study reveals that CeO 2 -Al 2 O 3 is an excellent support for this process helping to achieve high degrees of CO 2 conversions. Interestingly, FeO x and CrO x , which are well-known active components for the forward shift reaction, have opposite effects when used as promoters in the RWGS reaction. The use of iron remarkably boosts the activity, selectivity and stability of the Ni-based catalysts, while adding chromium results detrimental to the overall catalytic performance. In fact, the iron-doped material was tested under extreme conditions (in terms of space velocity) displaying fairly good activity/stability results. This indicates that this sort of catalysts could be potentially used to design compact RWGS reactors for flexible CO 2 utilisation units.

Catalytic Steam Reforming of Toluene: Understanding the Influence of the Main Reaction Parameters over a Reference Catalyst

“…When reforming is envisaged as a downstream tar upgrading unit after gasification, the most interesting temperature interval for atmospheric reforming is between 600 and 900 • C, since the gasification effluent temperature will normally be lower than 900 • C [33]. Research also suggested that high temperature might reduce H 2 yield as the reverse water-gas shift reaction is favoured due to its endothermic nature [34][35][36]. The experiments were conducted at different temperatures to investigate the most suitable conditions for toluene conversion and H 2 production.…”

CO2 Hydrogenation over Nanoceria-Supported Transition Metal Catalysts: Role of Ceria Morphology (Nanorods versus Nanocubes) and Active Phase Nature (Co versus Cu)

“…Regardless of the hydrogen inlet concentration, CO2 conversion approached the respective equilibrium values within ~5% at around 380 °C. Several catalytic systems employed for rWGS have been reported to function under thermodynamic limitation at the medium-high or high temperature regime [103][104][105]. As for the selectivity to CH4, it increased slightly, from about 1.0% for a H2:CO2 ratio of 1:1 to 5.1% for a ratio of 9:1.…”

Noble-metal-free and Pt nanoparticles-loaded, mesoporous oxides as efficient catalysts for CO2 hydrogenation and dry reforming with methane

“…Ru [27], Cu [28][29][30], Fe [31,32], and Ni [33,34] have been utilized. Various supports such as CeO 2 [28,35,36] , SiO 2 [37,38] , Al 2 O 3 [39,40] , ZrO 2 [29] , TiO 2 [25,41] , zeolite [13] have been used.…”