The changing paradigm in CO2 utilization

CO2 is today at the centre of the attention of scientists and technologists for its potential as source of carbon in the synthesis of chemicals and fuels. The actual utilization of CO2 although significant for the chemical industry (ca. 200 Mt/y) represents a minor fraction of the anthropogenic emission (32,000 Mt/y). So far, only thermal routes were exploited, based on the use of fossil carbon as source of energy. This has brought to the exploitation of low-energy reactions, making a few chemicals. The changing paradigm in the use of perennial energy sources such as solar-, wind- and geothermal-energy, makes possible the exploitation of reactions that are more energy intensive and bring to products such as fuels that have a large market. This paper makes an analysis of the potential of several applications, highlighting barriers to a large scale conversion and identifying technologies that can make possible and economically acceptable the conversion of CO2 into fuels. Cycling large volumes of CO2 represents a way to control both its immission into the atmosphere and the extraction of fossil fuels.