Valorization of sugarcane bagasse and straw through dilute acid hydrolysis for xylitol production: Operating conditions and process modeling

Abstract

Since 1970, xylitol has been used in foods, pharmaceuticals, and health products such as gum, dental paste, and toothpaste. At the industrial level, xylitol is produced by chemical processes (catalytic xylose hydrogenation), as the biotechnological route that has been widely studied in the last decade currently has bottlenecks such as energy consumption in some stages of the process (Morakile et al., 2022). However, it is still necessary to carry out techno-economic analyses of the conceptual process to identify areas for improvement. The present study evaluates the operational process production of xylitol by the biotechnological route using bagasse and sugarcane straw as the raw materials for the process. This process is studied using acid hydrolysis to produce xylose which subsequently undergoes a fermentation process to obtain xylitol. In Chapter 1, the biotechnological process for xylitol production was studied with variations in the operating conditions of one of the costliest stages of the process, with the objective of obtaining higher yields of xylose. Fermentation of the hydrolyzate obtained was performed and compared with synthetic medium fermentations supplied with different nitrogen sources. Likewise, the design of the process focused on the treatment of the hydrolysis product was studied, which has shown to be important in the final productivity and in the projection of scaling up to industrial level. In Chapter 2, the results of the operating conditions and information in the literature were used to design the conceptual process and build a first model that describes the relationship between raw material input and xylitol production. Also, the financial feasibility of scaling up the process in the Colombian context was analysed.