Michigan Biotechnology Institute (MBI) 1 article published in JoVE Environment Ammonia Fiber Expansion (AFEX) Pretreatment of Lignocellulosic Biomass Shishir P. S. Chundawat1, Ramendra K. Pal1, Chao Zhao1, Timothy Campbell2, Farzaneh Teymouri2, Josh Videto2, Chandra Nielson2, Bradley Wieferich3, Leonardo Sousa3, Bruce E. Dale3, Venkatesh Balan4, Sarvada Chipkar5, Jacob Aguado5, Emily Burke5, Rebecca G. Ong5 1Department of Chemical and Biochemical Engineering, Rutgers-State University of New Jersey, 2Michigan Biotechnology Institute (MBI), 3Department of Chemical Engineering and Materials Science, Michigan State University, 4Engineering Technology Department, Biotechnology Program, College of Technology, University of Houston, 5Department of Chemical Engineering, Michigan Technological University Ammonia fiber expansion (AFEX) is a thermochemical pretreatment technology that can convert lignocellulosic biomass (e.g., corn stover, rice straw, and sugarcane bagasse) into a highly digestible feedstock for both biofuels and animal feed applications. Here, we describe a laboratory-scale method for conducting AFEX pretreatment on lignocellulosic biomass.