Page 280 - Refining Biomass Residues for Sustainable Energy and Bioproducts

248 Refining Biomass Residues for Sustainable Energy and Bioproducts

context, hydrogen production from a renewable source is sustainable and green pro-
cess. Biohydrogen is produced by fermentation. The common bacterial species
involved are Clostridium sp. and facultative anaerobe of Enterobacteriaceae family
(Seol et al., 2008). Agroresidues serve as a potential source for biohydrogen produc-
tion (Hay et al., 2013; Cheng et al., 2001). Mostly pretreated lignocellulosic bio-
masses are utilized for the production of biohydrogen. Few reports are there for the
production of biohydrogen from nonpretreated lignocellulosic biomass (Talluri et al.,
2013; Li et al., 2012). The study revealed that biohydrogen yield is better from pre-
treated biomass when compared to the native one. Several research and developmen-
tal activities are going on for the development of an economically viable process.
Sheng et al. (2018) developed a strategy for the production of biohydrogen from
fungal pretreated rice straw. The biomass was treated with an edible fungus named
Gymnopus contrarius J2 at room temperature for a period of 2 weeks. Under this
condition, 5.71 mmol/g of biohydrogen was produced. This yield was 74% higher
when compared to the biohydrogen produced from unpretreated rice straw. The
study revealed that fungal pretreatment removed 22.4% of lignin from the rice
straw.
Dong et al. (2018) developed a novel pretreatment method using alkali/urea at
low temperature for enhanced biohydrogen production. Different alkali/urea combi-
nations were evaluated and the results indicate that NaOH/urea pretreatment at low
temperature (28 Cto 220 C) exhibited the best pretreatment results by better lig-

nin removal and preserving cellulose and hemicelluloses in the pretreated biomass.
Fermentation of the pretreated biomass by Thermoanaerobacterium thermosacchar-
olyticum M18 showed a biohydrogen yield of 22.08 mmol/L. This is 161.92%
increased biohydrogen production when compared to native rice straw.
Sattar et al. (2016) compared a biohydrogen production potential of pretreated
rice straw codigested with sludge in an anaerobic reactor. Rice straw was pretreated
under three different conditions—mechanical, steam explosion, and chemical using
NaOH. The results indicate that the highest biohydrogen production as well as lig-
nin removal was observed with NaOH-pretreated rice straw. Under optimized con-
ditions, 60.6 mL/g was obtained.

11.2.1.4 Biogas
Vasmara et al. (2017) evaluated biogas production from pretreated wheat straw.
Pretreatment was carried out with sodium hydroxide. Biogas production was evalu-
ated with both pretreated and native wheat straw. The study revealed that sodium
hydroxide pretreated wheat straw gave better biogas production than the native
one. Joelsson et al. (2016) developed a strategy for combined bioethanol and biogas
production at high solids loading from steam-pretreated wheat straw impregnated
with acetic acid. Pretreated biomass was used for bioethanol production, while the
effluent generated during pretreatment was evaluated for biogas production.