Fourier-Tranform Infrared Spectroscopy Studies on Interactions of Carboxylic Acids with Cellobiose
Abstract: Green chemistry is ever evolving and development of efficient methods for the preparation of sustainable materials from renewable resources is a current, high priority research interest. Cellulose is one of the most abundant bio-polymers on earth and depolymerization of cellulose to glucose is a major pathway to produce sustainable feedstock chemicals.
Due to the structural complexity of cellulose, this study uses cellobiose as a model compound for cellulose. Cellobiose (C12H22O11) is a section of the cellulose structure and can be classified as a disaccharide. It can be harvested from cellulose via enzymatic or acidic hydrolysis. In this study interactions of dicarboxylic acids with cellobiose were studied using infrared (IR) spectroscopy. The dicarboxylic acids used in this study are; cyclohexane-1,4-dicarboxylic, oxalic, malonic, succinic, phthalic, lactic, and tartaric acids.
Experimentation involves the preparation of homogenous mixtures of cellobiose and dicarboxylic acids using the measurement of IR spectra in the solid state. The IR spectra of these mixtures were examined for shifts and changes in IR absorptions, which is indicative of changes in bond strengths in the carboxylic acids and cellobiose due to intermolecular interactions.
We have found that oxalic and maleic acids give high IR absorption shifts in comparison to other acids studied. This is probably due to these two dicarboxylic acids strongly interacting with OH groups of cellobiose through hydrogen bonding type dipolar interactions.
These results will be used in the development of polycarboxylic acid based cellulose hydrolysis catalyst systems for the efficient production of glucose.
Ananda Amarasekara, Ph.D.*, Yen Maroney Lawrence
Judging Forms – Official judges only