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Biodiesel production faces environmental and economic challenges due to the use of homogeneous catalysts, such as NaOH, KOH, NaOCH 3 , and KOCH 3. Despite their good activity, these catalysts are toxic and almost impossible to recycle/reuse. Heterogeneous catalysts, otherwise, can be reused and easily separated from the final product, resulting in more sustainable and cost-effective production. However, these catalysts leach, losing activity through reaction cycles and contaminating the biodiesel This review has therefore addressed the use of CaO – a promising catalyst for biodiesel synthesis – and various biochar-derived catalysts. Particular attention was paid to studies involving the use of CaO in a biochar matrix (CaO/Biochar), given the support essential role in making the CaO use feasible. The use of catalysts derived from sugarcane bagasse biochar was also highlighted, given this biomass importance, especially in Brazil. Studies have shown that biochar-derived catalysts have good activity, excellent stability, and can be reused for up to 10 cycles. Concerning CaO/Biochar, it was found that biochar significantly reduced Ca2+ leaching, but there is still a need to further reduce the Ca2+ release into biodiesel. There is also a need to give more focus on CaO leaching. Finally, a lack of studies on the use of catalysts derived from sugarcane bagasse biochar is notiable, showing no study involving the CaO-embedded sugarcane bagasse biochar. • There are no studies about biodiesel synthesis with CaO/Sugarcane biochar. • Biochars from different sources significantly reduced the Ca2+ leaching. • Biochar-based catalysts provided nearly 100 % biodiesel yield under relatively mild conditions. • Biochar support significantly increases catalysts' reusability. • Ca– O –Si bonds may be associated with the CaO anchoring. [ABSTRACT FROM AUTHOR]

Production of biofuels via biomass pyrolysis has received a strong emphasis since it may produce a wide variety of renewable fuels in liquid (bio-oil), solid (biochar), and gas (syngas) forms. Sugarcane bagasse, waste from the sugar-alcohol industry, is largely produced in Brazil, India, and Thailand and appears as a great biomass option for pyrolysis due to its properties, abundance, and current underutilization. However, sugarcane bagasse properties and pyrolysis operating conditions may directly affect the product properties, distribution, and further application as fuels and chemicals. Thus, it is necessary a thorough study of these subjects. This review brings an overview of biomass and pyrolysis concepts, as well as a collection of improvements in the production of products (bio-oil, biochar, and gas) via sugarcane bagasse pyrolysis. In addition, this review discusses the interaction between process operating conditions and this biomass type to address how the products' properties and yields are affected. • Fast Pyrolysis: an efficient thermochemical process for bio-oil, biochar, and gas production. • Fast Pyrolysis concepts, operational conditions, and reactor configurations were reviewed. • Bio-oil, biochar, and gas production as an alternative for renewable energy world matrix. • Focus on sugarcane bagasse as a raw material for bio-oil, biochar, and gas production. • Upgrading methods for bio-oil, challenges, and future works in the pyrolysis field. [ABSTRACT FROM AUTHOR]