Enhancing CO2 Hydrogenation to Methane by Ni-Based Catalyst with V Species Using 3D-mesoporous KIT-6 as Support

The Route from Green H2 Production through Bioethanol Reforming to CO2 Catalytic Conversion: A Review

Currently, a progressively different approach to the generation of power and the production of fuels for the automotive sector as well as for domestic applications is being taken. As a result, research on the feasibility of applying renewable energy sources to the present energy scenario has been progressively growing, aiming to reduce greenhouse gas emissions. Following more than one approach, the integration of renewables mainly involves the utilization of biomass-derived raw material and the combination of power generated via clean sources with conventional power generation systems. The aim of this review article is to provide a satisfactory overview of the most recent progress in the catalysis of hydrogen production through sustainable reforming and CO2 utilization. In particular, attention is focused on the route that, starting from bioethanol reforming for H2 production, leads to the use of the produced CO2 for different purposes and by means of different catalytic processes, passing through the water–gas shift stage. The newest approaches reported in the literature are reviewed, showing that it is possible to successfully produce “green” and sustainable hydrogen, which can represent a power storage technology, and its utilization is a strategy for the integration of renewables into the power generation scenario. Moreover, this hydrogen may be used for CO2 catalytic conversion to hydrocarbons, thus giving CO2 added value.

Hydrogenation of carbon dioxide (CO2) to fuels in microreactors: a review of set-ups and value-added chemicals production

A review of CO2 hydrogenation to fuels and value-added chemicals in microreactors.

Co-Precipitated Ni-Mg-Al Hydrotalcite-Derived Catalyst Promoted with Vanadium for CO2 Methanation

Co-precipitated Ni-Mg-Al hydrotalcite-derived catalyst promoted with vanadium were synthesized with different V loadings (0–4 wt%) and studied in CO₂ methanation. The promotion with V significantly changes textural properties (specific surface area and mesoporosity) and improves the dispersion of nickel. Moreover, the vanadium promotion strongly influences the surface basicity by increasing the total number of basic sites. An optimal loading of 2 wt% leads to the highest activity in CO₂ methanation, which is directly correlated with specific surface area, as well as the basic properties of the studied catalysts.

Non-noble MNP@MOF materials: synthesis and applications in heterogeneous catalysis

Transition metals have a long history in heterogeneous catalysis. Noble or precious transition metals have been widely used in this field. The advantage of noble and precious metals is obvious in 'heterogeneous catalysis'. However, the choice of Earth abundant metals is a sustainable alternative due to their abundance and low cost. Preparing these metals in the nanoscale dimension increases their surface area which also increases the catalytic reactions of these materials. Nevertheless, metals are unstable in the nanoparticle form and tend to form aggregates which restrict their applications. Loading metal nanoparticles (MNPs) into highly porous materials is among the many alternatives for combating the unstable nature of the active species. Among porous materials, highly crystalline metal-organic frameworks (MOFs), which are an assembly of metal ions/clusters with organic ligands, are the best candidate. MOFs, on their own, possess catalytic activity derived from the linkers and metal ions or clusters. The catalytic properties of both non-noble metal nanoparticles (MNPs) and MOFs can be improved by loading non-noble MNPs in MOFs yielding MNP@MOF composites with a variety of potential applications, given the synergy and based on the nature of the MNP and MOF. Here, we discussed the synthesis of MNP@MOF materials and the applications of non-noble MNP@MOF materials in heterogeneous catalysis.

Preparation of MCM-41 supported nickel NPs for the high-efficiency semi-hydrogenation of acetylene

High-efficiency nonnoble-metal catalysts for acetylene hydrogenation.

Promising Catalytic Systems for CO2 Hydrogenation into CH4: A Review of Recent Studies

The increasing utilization of renewable sources for electricity production turns CO2 methanation into a key process in the future energy context, as this reaction allows storing the temporary renewable electricity surplus in the natural gas network (Power-to-Gas). This kind of chemical reaction requires the use of a catalyst and thus it has gained the attention of many researchers thriving to achieve active, selective and stable materials in a remarkable number of studies. The existing papers published in literature in the past few years about CO2 methanation tackled the catalysts composition and their related performances and mechanisms, which served as a basis for researchers to further extend their in-depth investigations in the reported systems. In summary, the focus was mainly in the enhancement of the synthesized materials that involved the active metal phase (i.e., boosting its dispersion), the different types of solid supports, and the frequent addition of a second metal oxide (usually behaving as a promoter). The current manuscript aims in recapping a huge number of trials and is divided based on the support nature: SiO2, Al2O3, CeO2, ZrO2, MgO, hydrotalcites, carbons and zeolites, and proposes the main properties to be kept for obtaining highly efficient carbon dioxide methanation catalysts.

Understanding Catalysis—A Simplified Simulation of Catalytic Reactors for CO2 Reduction

The realistic numerical simulation of chemical processes, such as those occurring in catalytic reactors, is a complex undertaking, requiring knowledge of chemical thermodynamics, multi-component activated rate equations, coupled flows of material and heat, etc. A standard approach is to make use of a process simulation program package. However for a basic understanding, it may be advantageous to sacrifice some realism and to independently reproduce, in essence, the package computations. Here, we set up and numerically solve the basic equations governing the functioning of plug-flow reactors (PFR) and continuously stirred tank reactors (CSTR), and we demonstrate the procedure with simplified cases of the catalytic hydrogenation of carbon dioxide to form the synthetic fuels methanol and methane, each of which involves five chemical species undergoing three coupled chemical reactions. We show how to predict final product concentrations as a function of the catalyst system, reactor parameters, initial reactant concentrations, temperature, and pressure. Further, we use the numerical solutions to verify the “thermodynamic limit” of a PFR and a CSTR, and, for a PFR, to demonstrate the enhanced efficiency obtainable by “looping” and “sorption-enhancement”.