EAGER: Catalytic Transformation and Kinetics of Lignin-Carbohydrate Complexes

William Marsh Rice University, Houston TX

Investigators

Abstract

ABSTRACT Intellectual Merit: Lignocellulose can be thought as a spatially and compositionally complex mixture of cellulose, hemicellulose, and lignin. There has been great progress in understanding and controlling the breakdown chemistry of cellulose and hemicellulose, in the upconversion of their constituent carbohydrate intermediates into ethanol, BTX, furans, and other chemical species. In contrast, there is less progress on lignin and the effect of lignin interaction with cellulosic components during the process. The association of lignins with carbohydrates presents a serious challenge for the utilization of lignocellulosic biomass. This proposal from Investigators Michael Wong of William Marsh Rice University and Conrad Zhang of KiOR Inc. describes a one-year collaborative research plan between the university and industrial corporation that focuses on the "interface" chemistry between the building units of lignin and cellulose of different feeds, and to study the impact of this chemistry on the rate and product distribution profiles during a thermocatalytic conversion process. Unlike other studies which either focus solely on model lignin or cellulose breakdown products, this project focuses on lignin-carbohydrate complexes (LCCs) as a model of a lignocellulose breakdown intermediate. It is hypothesized that the pyrolytic decomposition of lignocellulose generates LCCs as a chemical intermediate, and its chemistry is, so far, not accounted for. The goals of this work are to determine the heterogeneously catalyzed transformation routes and kinetics of LCCs, and to establish some general criteria for designing catalytic materials that can control LCC transformation pathways and kinetics. Broader Impacts: The renewed academic and industrial interest in lignocellulosic biomass as a sustainable source of fuel, chemicals, and energy has been tremendous, in response to the worldwide concerns of energy security, global warming, and sustainable development. Various approaches to convert lignocellulose into higher-value products are being investigated, with catalytic conversion into transportation fuel and basic chemicals as a promising direction. The unknown nature of the "interface" between the lignin and cellulose fractions in lignocellulose presents technical challenges in the catalytic upconversion of biomass. Studying lignincarbohydrate complexes addresses these challenges, potentially lowering the activation barrier to improvements in commercialization. This project, as a collaboration between a university and a company, will also provide for the multidisciplinary training of 1 post-doctoral research associate in chemical kinetics, heterogeneous catalysis, and materials chemistry, state-of-the-art analytical techniques, and industrial collaborations. The post-doctoral member will receive guidance and training according to a well-defined postdoctoral mentoring plan.