There is a growing need to find other alternatives to crude oil as the primary feedstock for the chemicals and fuels industry. Ethanol has many desirable features as a petroleum substitute and could help make a smoother transition from a petroleum-based to a bio-based chemical economy. Ethanol is produced in large quantities from natural resources including corn grain and sugarcane juice. However, there is a need to find an inexpensive and widely available lignocellulosic source of biomass (i.e. corn stover, rice straw, wheat straw) to avoid feedstock conflict with the prevalent food industry. Lignocellulosic recalcitrance is one of the primary impediments in the successful implementation of a cellulosic ethanol based biorefinery. AFEX is a leading pretreatment process to pretreat biomasses which reduce this intrinsic recalcitrance and is critical to help improve bioconversion.

Rice straw is an important lignocellulosic biomass with nearly 800 million dry tons produced annually worldwide. In addition to glucan and xylan it has about 10-15% silica which could be valuable byproducts if processed after enzymatic hydrolysis. Rice straw therefore has great potential as a lignocellulosic feedstock for making renewable fuels and chemicals. We will present the complete process optimization which includes pretreatment, enzymatic hydrolysis and fermentation to produce maximum ethanol using different ethanologens like yeast and bacteria.