Synthesis and Characterization of Cellulose Acetate from Kombucha SCOBY Bacterial Cellulose Using Different Acetylating Agents

Kombucha bacterial cellulose (KBC) is an exopolysaccharide synthesized by bacteria in the process of fermenting kombucha tea. It has a distinct three-dimensional reticulated network made of cellulose nanofibers, which gives it robust mechanical qualities, a high water-holding capacity, and outstanding suspension stability. Cellulose acetate (CA) is a very important derivative generated via transesterification. As an economical ester of cellulose, CA is used in retractable films, fibers, filters, and tubes because of its good mechanical qualities, low density with larger surface area, biodegradability, and nontoxicity. This study focuses majorly on two aspects: (1) the production of high-value yields (cellulose acetate) by using low-value waste (tea processing waste) for the cultivation of bacterial cellulose to address the challenges associated with high production costs, plastic waste, and limitations of utilizing cellulose derivatives (2) Selection of the better acetylating agent among acetic acid and acetic anhydride for conversion of KBC. CA was synthesized via two methods: using acetic acid (CA1) and acetic anhydride (CA2) wherein using the first method, the % acetyl group of 11.82 was obtained, whereas a two-fold increase in the % acetyl group (23.65) was observed using the second method. Further, the characteristic peaks observed in FTIR analysis confirmed the acetylation of KBC. CA2 showed lower crystallinity and higher thermal stability than CA1. Thus, this study demonstrated the synthesis of CA using acetic anhydride as a better method from KBC for use as a sustainable alternative to existing plastic-based and plant-based cellulose acetates. The novelty of this research lies in its innovative approach and comparative study to produce cellulose acetate by utilizing low-value waste to achieve a high-value output like better yield, crystallinity, and thermal stability. It presents an environmentally friendly substitute for plastic-based cellulose acetates.