Circular chemistry (CC) is an approach for establishing chemical processes to become truly circular and sustainable. It adopts the principles of circular economy (CE), employing life cycle approaches and systems thinking, which help to understand and address the sustainability issues of chemical processes and products. Within this whole context, it is possible to identify some problems of the current lifestyle, such as plastic waste disposal, CO2 emission, e-waste, among others, which need to be addressed accordingly. The reuse provided, well-structured within the context of circular chemistry, can bring benefits in all spheres: social, environmental and economic. Thus, the purpose of this revision is to present CE and CC as the pillars for a sustainable development, bringing discussions about: CE and CC systems; sustainable chemistry; and chemistry 4.0, which embeds digitization, sustainability, and circular economy in industrial chemical processes. Through the knowledge of chemistry, both CC and CE can contribute with innovative methods and processes which maximize benefits, eliminating, or, at least, reducing adverse impacts, thus contributing to construct a mutually beneficial relationship between science and society, its surroundings, and the environment. Therefore, implementing this new model is an opportunity that challenges the human imagination in building a better world.

The glycerol oxidative dehydration to organic compounds, especially acrolein and acrylic acid, was studied over vanadium, molybdenum, and cobalt oxides supported on niobium oxide and niobium phosphate catalysts. At 300 °C, the glycerol conversion was 100% over all catalysts tested, and acrolein was the main product observed, without significant deactivation within the time on stream studied. Except for Co/V/Nb2O5, acrylic acid was formed over all catalysts, but the selectivity was not higher than 10%. Acetaldehyde and acetic acid were the other organic oxygenated products formed. Although the catalysts supported over Nb2O5 presented significantly lower acidity than the catalysts supported over NbOPO4, they showed 100% glycerol conversion, indicating that the dehydration of glycerol does not require strong acidity. These data indicate the potential of niobium-based supports in the development of an active and selective catalyst for the glycerol oxidehydration to acrolein and acrylic acid, chemicals of great importance in the industry.