The environmental and climate program demands technological solutions in the chemical industry that incorporate prevention of pollution. This book concerns the analysis of the advantages of using compressed CO2 to produce not only improved materials in a better way, but also new nanoproducts. Recovering and using CO2, otherwise released into the atmosphere, is a means of recycling emissions resulting from other users. The use of supercritical CO2 is a complex option from a conceptual point of view requiring enhanced technical preparation.