CO2 hydrogenation to methanol: the structure–activity relationships of different catalyst systems

Abstract

CO 2 hydrogenation to methanol is a promising environmental-friendly route for combatting CO 2 emissions. Methanol can be used to produce a variety of chemicals and is also an alternative fuel. The CO 2-tomethanol process is mostly studied over multi-component catalysts in which both metal and oxide phases are present. The difficulty in elucidating the influence of the different phases on the catalytic performance has led to intense debate about the nature of the active site. Consequently, the main stumbling blocks in developing rational design strategies are the complexity of the multi-component catalytic systems and challenges in elucidating the active sites. In this paper, we reviewed the most promising catalyst systems for the industrial CO 2-to-methanol processes. Firstly, the copper-based catalysts are discussed. The focus is on the debate regarding the promotional effect of zinc, as well as other metal oxides typically employed to enhance the performance of copper-based catalysts. Other catalytic systems are then covered, which are mainly based on palladium and indium. Alloying and metal-metal oxide interaction also play a significant role in the hydrogenation of CO 2 to methanol over these catalysts. The purpose of this work is to give insight into these complex catalytic systems that can be utilized for advanced catalyst synthesis for the industrial CO 2-to-methanol process.

Conversion of Carbon Dioxide into Methanol Using Cu–Zn Nanostructured Materials as Catalysts

“…These catalysts were zinc oxide with and without PVP and Cu/ZnO with PVP. As stated in the literature [ 27 ], the catalytic activity and methanol selectivity can be correlated with the increase in Zn 0 concentration. It was discovered that a zinc enrichment in the catalyst leads to greater activity and methanol selectivity due to two factors: improving the Cu and ZnO interactions that increase carbon dioxide hydrogenation and inhibiting the RWGS reaction, which produces carbon monoxide [ 34 ].…”

“…In particular, the results indicate that methanol was hardly obtained with copper—only at high temperatures and with non-significant concentrations of methanol. The lower activity of the copper was suggested to result from formate poisoning of the copper surface, which is an intermediate of the hydrogenation of carbon dioxide into methanol [ 27 ]. Furthermore, copper was found to be ineffective as a catalyst material for its low surface area [ 28 ].…”

Liquid Metals in Catalysis for Energy Applications

“…95 The anomaly in these findings motivates the search for new catalyst combinations to obtain different synergies that enhance catalytic activity. However, determining the roles of the different alloy constituents in the reaction is a challenging task, 104,105 and unequivocal conclusions regarding mechanisms and contributions are often difficult to make.…”

Recent Progress in Direct DME Synthesis and Potential of Bifunctional Catalysts

“…In line with the high importance, a large number of review articles exist on catalysts for methanol synthesis. In this context, reference should be made to some recent review articles on the relevant research topics ''Conversion of Carbon Dioxide'', [24][25][26][27][28][29] ''Bimetallic Catalysts'' [25], ''Methanol Production'' [26]. The following sections summarize current developments on the most important catalyst groups for application in fundamental research and process development for methanol synthesis.…”