NMR SEM Biochar a b s t r a c t The influence of temperature and heating rate on the yield and properties of biochar derived from pyrolysis of solid olive mill waste (pomace) was investigated. Three pyrolysis temperatures (430 ± 10 C, 480 ± 10 C and 530 ± 10 C) and 3 heating rates (25 C min À1 , 35 C min À1 and 45 C min À1) were studied. The biochar production was carried out using a vertical downdraft gasifier. Increasing the pyrolysis temperature, and/or the heating rate, the biochar yield lowered, the C content and biochar aromaticity increased and the surface functional groups were reduced. The highest biochar yield was obtained by low pyrolysis temperature (430 ± 10 C) and low heating rate (25 C min À1). This biochar is characterized by a high heating value (31 MJ/kg) that makes it a possible fuel candidate and, in the meantime, due to its high concentration in C (70.2%e84.1%), low electrical conductivity (0.28 dS m À1 e0.47 dS m À1) and the lack of phytotoxicity it is suitable for amendment in agricultural soils and for long term carbon sequestration.