Graduate Studies


Date of this Version

Summer 8-2012


A THESIS Presented to the Faculty of The Graduate College at the University of Nebraska In Partial Fulfillment of Requirements For the Degree of Master of Science, Major: Agricultural and Biological Systems Engineering, Under the Supervision of Professor Deepak R. Keshwani. Lincoln, Nebraska: August, 2012

Copyright (c) 2012 Rachna Dhir


Lignocellulosic (plant) biomass is a promising feedstock for ethanol production. This thesis examines the biochemical process of converting lignocellulosic biomass into ethanol. The biochemical conversion process involves depolymerizing the carbohydrates (cellulose and hemicellulose) present in lignocellulosic biomass into fermentable sugars. Considerable challenges exist in realizing the ethanol production potential of lignocellulosic biomass. A review of current research on biochemical conversion of lignocellulosic biomass is presented in Chapter 1. The factors effecting separate hydrolysis and fermentation, and simultaneous saccharification and fermentation are discussed. In Chapter 2, a novel approach using a fuzzy inference system is presented to model the dilute acid pretreatment of lignocellulosic biomass. Two different clustering methods were used, and models were optimized in each case. Additionally, a sensitivity analysis of each model was conducted. In Chapter 3, the effects of particle size and solid loading on the enzymatic hydrolysis of pretreated lignocellulosic biomass were investigated. The effects of these parameters on the conversion of glucan and xylan are discussed.

Adviser: Deepak R. Keshwani