Enzymatic sacchariﬁcation and fermentation of paper and pulp industry efﬂuent for biohydrogen production Rajendran Lakshmidevi, Karuppan Muthukumar* Department of Chemical Engineering, Alagappa College of Technology Campus, Anna University Chennai, Chennai 600 025, India article info Article history: Received 25 October 2009 Received in revised form 25 December 2009 Accepted 26 December 2009 Available online 10 February 2010 Keywords: Paper and pulp efﬂuent Enzymatic hydrolysis Biohydrogen production Enterobacter aerogenes abstract Paper and pulp industry efﬂuent was enzymatically hydrolysed using crude cellulase enzyme (0.8–2.2FPU/ml) obtained from Trichoderma reesei and from the hydrolysate bio- hydrogen was produced using Enterobacter aerogenes. The inﬂuence of temperature and incubation time on enzyme production was studied. The optimum temperature for the growth of T. reesei was found to be around 29  C. The enzyme activity of 2.5 FPU/ml was found to produce about 22 g/l of total sugars consisting mainly of glucose, xylose and arabinose. Relevant kinetic parameters with respect to sugars production were estimated using two fraction model. The enzymatic hydrolysate was used for the biohydrogen production using E. aerogenes. The growth data obtained for E. aerogenes were ﬁtted well with Monod and Logistic equations. The maximum hydrogen yield of 2.03 mol H 2 /mol sugar and speciﬁc hydrogen production rate of 225 mmol of H 2 /g cell/h were obtained with an initial concentration of 22 g/l of total sugars. The colour and COD of efﬂuent was also decreased signiﬁcantly during the production of hydrogen. The results showed that the paper and pulp industry efﬂuent can be used as a substrate for biohydrogen production. ª 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved. 1. Introduction The rapid industrialization with an increase in energy consumption resulted in the exhaustion of fossil fuels and energy insecurity. The persistent need for energy and envi- ronmental impacts due to fossil fuels led to research focus on alternate fuels. Hydrogen is a non pollutable resource of energy with numerous advantages in terms of transportation having a widest range of combustible properties than other fuels [1]. Moreover the generation of electricity by coupling with fuel cells makes biohydrogen production as an attrac- tive one [2]. The production of biohydrogen from waste materials with zero emission of green house gases is an important one with respect to scientiﬁc and political concern [3,4]. Biohydrogen production from renewable resources minimizes waste accumulation and maintain a sustainable ecosystem and hence, it has been considered as a conserva- tive approach [5]. Paper and pulp industry, one of the prime industrial sectors, depends majorly on surplus quantity of lignocellu- losic components of plants. This industry is considered to be a main consumer of natural resources and chemicals for paper manufacturing. This contains fairly coarse suspended matter composed largely of cellulosic ﬁbres and other organic debris. The wastewater discharged from this industry has been characterised with high COD content, colour and toxicity and the presence of lignin impart dark brown colour to the efﬂuent [6]. The sludge generated by paper and pulp industry has been successfully used for the production of bioethanol [7]. An innovative method, which uses paper and pulp industry efﬂuent for the production of biohydrogen, was developed in the present study. * Corresponding author. Tel.: þ91 9444951977; fax: þ91 44 22352642. E-mail address: muthukumar@annauniv.edu (K. Muthukumar). Available at www.sciencedirect.com journal homepage: www.elsevier.com/locate/he international journal of hydrogen energy 35 (2010) 3389–3400 0360-3199/$ – see front matter ª 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.ijhydene.2009.12.165