Increasing of greenhouse gas emission, reduction of natural
resources, and low availability of fossil fuels insist the significance
of energy production from renewable resources (Chandra et al.,
2012). One of the possible and promising solutions is the production
of ethanol as a clean and renewable liquid fuel (Chen et al.,
2007).
Rice straw is one of the most abundant lignocellulosic waste
material all around the world. The estimation of annual production
of rice announced by FAO (Food and Agriculture Organization) was
about 721 million tons in 2011 (FAO, 2012). Each kg of rice grain
produces about 1–1.5 kg of rice straw leading to the presence of
about 900 million tons rice straw annually (Poornejad et al., 2013).
The common option of rice straw landfilling is limited due to the
great bulk of material, slow degradation in the soil, harboring of
rice stem diseases, and its high mineral content. Currently, field
burning is the main solution for rice straw depletion which causes
air pollution and consequently affects the public health(