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The in-field burning of sugarcane leaf residues presents a major environmental and health burden in Thailand. In this study, sugarcane leaves were converted into a biochar-based slow release phosphorus (P) fertilizer via pyrolysis at 600 °C, and the influence of pre- and post-pyrolysis treatment on the P loading and release was investigated. The sugarcane leaves were pre-treated with an alkaline (diammonium phosphate, DAP) or an acidic P source (phosphoric acid, PA), with or without addition of MgO. Additionally, the biochar was post-treated with DAP to increase the P loading. Extraction of P in DI water and 2% formic acid were used as indicators for potential slow release. The microporous biochars had a specific surface area of 69–333 m2 g−1 and pre-treatment resulted in a P content of 34–82 g kg−1. When MgO was included in the pre-treatment, XRD analysis confirmed formation of crystalline Mg 2 P 2 O 7 , irrespective of the P source. This Mg 2 P 2 O 7 was responsible for slow P release in DI water over 240 h via a dissolution-controlled process. Post-treatment with DAP increased the P loading to 156 g kg−1 in the form of water-soluble monoammonium phosphate (MAP), which did not contribute to slow release. The tunable P release via combinations of pre- and post-pyrolysis treatment makes these engineered biochars attractive as P sources for crops and presents an attractive solution to mitigate in-field sugarcane residue burning. [Display omitted] • P-loaded biochar was prepared by co-pyrolysis of sugarcane leaves with P + MgO. • Addition of MgO in pre-pyrolysis treatment results in slow release of P. • The slow P release is controlled by dissolution of Mg 2 P 2 O 7. • Post-treatment with DAP increases water-soluble P but not slow-release P. [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]