New Trends in Pyrolysis Methods: Opportunities, Limitations, and Advantages

Abstract

AbstractThe expanding demand for environmental treatment increasingly requires different types of engineered char with high performance. In this context, new trends in pyrolysis methods have emerged and contributed to the sustainable development of pyrolysis technologies, namely microwave-assisted pyrolysis, co-pyrolysis, pyrolysis under non-inert ambiances, hydrothermal carbonization (wet pyrolysis), and integrated pyrolysis techniques. The outstanding advantages of these technologies over conventional pyrolysis include: increase in biomass conversion efficiency of the process, use of nonconventional raw material, increase in adsorption capacity of biochar by enhanced activated oxygen species, porosity, and functional groups, and removal or immobility of contaminants. The biochar products can be widely applied in various environmental fields, such as carbon capture and sequestration, soil amendment, adsorption of contaminants in soil, water, and air, and energy production. Nevertheless, challenges remain for these new trends, such as the increase in cost for the installation and operation, the lack of knowledge of the mechanism involved during pyrolysis, the difficulty in scaling up, etc. Further studies are recommended to facilitate the application of these new trends, such as pilot tests or field experiments to evaluate the real effects of biochar products prior to large-scale applications or their long-term risk during use, or prediction of properties of biochar and their impacts on environmental applications using modeling or machine learning approaches.KeywordsAdvantagesBiocharLimitationNew trendsOpportunitiesPyrolysis