ABSTRACT This article presents the author`s viewpoint on a renewable energy scheme with good potential to support future sustainable development. This cycle is based on simple alcohols as efficient and convenient mid- to long-term (seasonal) hydrogen storage forms. In the synthesis, carbon dioxide trapped from concentrated sources or, ideally, from the atmosphere is proposed as a reactive “liquifier” for hydrogen produced from clean, renewable primary sources. The hydrogen fuel may be released on demand by co-reaction of alcohols and water, i.e., the reverse of the synthesis process. In the case of methanol, the relevant technology is close to technical maturity and offers early prospects for commercial implementation in the impending transition away from dependence on fossil fuel resources. Both methanol and ethanol will be important in the longer-term in view of their good economic outlook as renewable fuels from biomass gasification/synthesis and fermentation, respectively. The role of catalysis and catalytic reaction engineering in alternative industrial synthesis routes and in alcohol fuel processing will be vital to the ultimate success of the proposed energy scheme. Described here are the recent advances of major significance in carbon dioxide hydrogenation to liquid alcohol fuels, and the reverse process, i.e., steam-reforming of alcohols, reported in the field of thermal heterogeneous catalysis at both the fundamental and technical level. A short overview of the present state-of-the-art in CO2 recovery technologies is also included because of their physico-chemical bases, and their relevance to the energy cycle under consideration. More distant prospects for the electrocatalytic synthesis of alcohols from CO2, a recently revitalized field, will be briefly summarized.
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