Global warming has been presented as one of the biggest challenges of humanity. There are several initiatives led by the United Nations (UN) to reduce the problem, particularly the Conferences of the Parties (COP), which continuously encourage the scientific community to develop new technologies to mitigate the problem. In the International Year of Basic Sciences for Sustainable Development, it is essential to develop new technologies, adapted to the characteristics of the local territory, as well as the use of materials from biomass, which are discarded in the production process. We present herein absorption and adsorption as methods for capturing CO2 . We will discuss possibilities and potentialities of adsorption and absorption as sustainable CO2 capture techniques. For CO2 adsorption, the materials used are contextualized, with emphasis on the use of porous carbons and N-carbons, all originating from different biomass wastes, such as coffee husks, sugarcane bagasse, among others. For CO2 absorption, the possibilities of using atoxic and recyclable ionic liquids are discussed. We also highlight the feasibility of using glycerol, a material considered waste from the production of biodiesel.