Hydrogen production using cellulosic residues offers the possibility of waste minimization with renewable energy recovery. In the present study, heat-treated biomass purified from leachate was used as inoculum in batch reactors for hydrogen production fed with different concentrations of cellulose (2.5, 5.0 and 10 g/L), in the presence and absence of exogenous cellulase. The heat-treated biomass did not degrade cellulose and hydrogen production was not detected in the absence of cellulase. In reactors with cellulase, the hydrogen yields were 1.2, 0.6 and 2.3 mol H-2/mol of hydrolyzed cellulose with substrate degradation of 41.4, 28.4 and 44.7% for 2.5, 5.0 and 10 g/L cellulose, respectively. Hydrogen production potentials (P) varied from 19.9 to 125.9 mmol H-2 and maximum hydrogen production rates (R-m) were among 0.8-2.3 mmol H-2/h. The reactor containing 10 g/L of cellulose presented the highest P and R-m among the conditions tested. The main acid produced in reactors were butyric acid, followed by acetic, isobutyric and propionic acids. Bacteria similar to Clostridium sp. (98-99%) were identified in the reactors with cellulase. The heat-treated leachate can be used as an inoculum source for hydrogen production from hydrolyzed cellulose. Copyright (C) 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.