Michigan State University

United States of America, As Represented by the Secretary of Agriculture

Leonardo Da Costa Sousa

Venkatesh Balan

Bruce E Dale

Patricia J Slininger

Bruce S Dien

Stephanie R Thompson

Shishir Chundawat

Maureen A Shea Andersh

Maureen A Shea-Andersh

Albert M Cheh

A method is provided for pretreating cellulosic or lignocellulosic biomass comprising de-esterifying the biomass with an alkali treatment to produce de-esterified biomass; and pretreating the de-esterified biomass with ammonia to produce de-esterified ammonia pretreated biomass. In various embodiments, the de-esterified ammonia pretreated biomass has an amide concentration ranging from about 0.04 to about 25 mg/g biomass. In other embodiments, the amide concentration is no more than 0.04 mg/g biomass. Various ammonia pretreatment processes may be used, including liquid or gaseous ammonia pretreatments, including, but not limited to, liquid ammonium hydroxide pretreatments, various AFEX pretreatments, with or without biomass densification, and various cellulosic conversion pretreatments including 'COBRA' pretreatments. Products (e.g., animal feed) and systems are also disclosed.

De-esterification of biomass prior to ammonia pretreatment

A method to convert at least a majority of native cellulose Ito cellulose IIIin pretreated or untreated densified biomass is disclosed. The densified biomass (cellulosic or lignocellulosic) is pretreated with anhydrous liquid ammonia or liquid ammonia comprising a solution of at least 80% ammonia. The pretreating can be performed at a temperature from about 4&#xb0; C. to about 140&#xb0; C. and a pressure from about 14.7 to about 200 psi. In one embodiment, the densified cellulosic converting pretreatment process is followed by lignin extraction (LE). The total moisture content of the densified biomass and the solution is 30% or less and a weight ratio of liquid ammonia to the densified biomass is from about 0.3:1 to about 2:1. Various products and systems are also disclosed.

Pretreatment of densified biomass using liquid ammonia and systems and products related thereto

Several mutated strains ofare generated by repetitive culturing of the parent strain on two types of concentrated hydrolyzates and with ethanol-challenged xylose-fed continuous culture. Isolates collected from various enriched populations are screened and ranked based on relative xylose uptake rate and ethanol yield. Ranking on hydrolyzates with and without nutritional supplementation is used to identify those isolates with best performance across diverse conditions.

Yeast strains

Methods for producing extracted and digested products from pretreated lignocellulosic biomass are provided. The methods include converting native cellulose Ito cellulose IIIby pretreating the lignocellulosic biomass with liquid ammonia under certain conditions, and performing extracting or digesting steps on the pretreated/converted lignocellulosic biomass.

Methods for producing extracted and digested products from pretreated lignocellulosic biomass

Growing community of inventors

Okemos, MI, United States of America

Leonardo Da Costa Sousa