Optimizing nanocrystalline cellulose extraction from cigarette filters via sulfuric acid hydrolysis using Box-Behnken design

The increase in cigarette confiscation by the Royal Malaysian Customs Department led to cigarette burning, contributing to raw materials wastage. Cellulose-rich cigarette filters (CF) can yield nanocrystalline cellulose (NCC) with potential applications in advanced materials. The NCC can be obtained by using sulfuric acid in the acid hydrolysis process. While sulfuric acid hydrolysis is a widely used method for extracting NCC, there is a lack of optimization of its parameters tailored to the cigarette filter as the raw material. This gap hinders the ability to consistently produce high-yield NCC, especially from non-traditional cellulose sources like cigarette butts. This study focuses on optimizing the extraction of NCC via sulfuric acid hydrolysis, utilizing a Box-Behnken experimental design to determine the optimized process parameters. The effects of acid concentration (33–35%), reaction temperature (45–75°C), and hydrolysis time (40–90 min) on NCC yield percentage were evaluated. The FTIR confirmed the removal of non-cellulosic components from the CF without affecting the functional groups of cellulose, confirming that its structural integrity remains unaltered. Findings from this study recorded the highest yield by using sulfuric acid hydrolysis, which can reach up to 89.95% from the cigarette filters used. The findings provide a sustainable approach to turning zero-waste cigarettes’ raw materials into sustainable advanced materials.