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Fixed-bed pyrolysis constitutes a possible way for distributed production of bio-char and bio-oil from biomass.Most of the literature in this topic is devoted to lab scale reactors and small particle sizes.However, to reach a successful use of these technologies, it is necessary to have a better understanding of these processes at a technical scale, with the influence of heat and mass transfer phenomena.In this study fixed-bed batch pyrolysis of several kg is carried out with different materials: pine wood chips, beech wood spheres and cellulose waste.The temperature distribution in the fixed-bed influences the properties of the obtained bio-char.When the porosity of the bed is higher, as for cellulose waste, the heat transfer in the bed is lower and the temperatures in the bed are less uniform.When the temperatures are higher the O/C ratio of the obtained bio-char is decreased, as well as the volatiles content, due to there are less O-content functional groups.In woody bio-chars this also produces a decrease in the acidity, while in cellulosic bio-chars a higher acidity is obtained independently of the O/C ratio.