The presented research aimed at finding new ways to value hemp by-products (stalks) from the cannabidiol industry through thermochemical conversion. Chemical and elemental composition of hemp biomass was investigated by successive chemical extractions and Scanning Electron Microscopy along with Energy-dispersive X-ray Spectroscopy. Proximate and elemental analyses completed the chemical characterization of the hemp biomass and its biochar. Thermogravimetric analysis of the hemp biomass allowed to understand its kinetic of decomposition during thermal conversion. The carbon structure and porosity of the biochar were assessed by Raman spectroscopy and CO₂ gas adsorption. Properties of interest were the energy production measured through calorific values, and the electrical conductivity. Two ways of valorisation of the hemp biomass were clearly identified, depending mainly on the chosen pyrolysis temperature. Hemp biochar carbonized at 400–600°C were classified as lignocellulosic materials with a good potential for solid biofuel applications. Specifically, the resulting carbonized biochar presented low moisture content (below 2.50%) favourable for high fuel quality, low volatile matter (27.1–10.4%) likely to show lower particle matter emissions, limited ash content (6.8–9.8%) resulting in low risk of fouling issues during the combustion, high carbon content (73.8–86.8%) suggesting strong energy density, associated with high higher heating values (28.45–30.95 MJ kg⁻¹). Hemp biochar carbonized at 800–1000 °C displayed interesting electrical conductivity, opening opportunities for its use in electrical purposes. The electrical conductivity was related to the evolution of the biochar microstructure (development of graphite-like structure and changes in microporosity) in regard with the thermochemical conversion process parameters. Graphical abstract

The use of biomass, such as seed husks, for fuel production through pyrolysis is a key technology aimed at replacing fossil fuels with renewable energy sources, thereby contributing to a cleaner environment. This study assesses the energy potential and chemical composition of the husks of Ricinodendron heudelotii, highlighting their suitability for biofuel production. The proximate analysis of the kernel husks revealed ash, volatile matter, fixed carbon, and moisture contents of 18.80%, 59.80%, 21.40%, and 8.60%, respectively. The elemental analysis showed carbon, hydrogen, and nitrogen ratios of 47.0%, 4.52%, and 0.54%, respectively. Additionally, the lower heating value was determined to be 18.29 MJ/kg for the husks (dry basis). This composition, comparable to that of other energy crops cultivated globally for energy production, suggests that R. heudelotii could compete with standardized species used as raw materials for biofuels. This study opens up new possibilities for using Ricinodendron heudelotii husks as significant woody biomass fuel for domestic or industrial heating.