Response Surface Optimization of Cellulose-Rich Material Recovery from Carludovica palmata Fibers: Effects on Structural and Thermal Properties

This study optimized the chemical treatment conditions for Carludovica palmata fibers using response surface methodology (RSM) based on central composite designs (CCDs). Acid and alkaline treatments were evaluated as independent experimental routes to determine the effects of reagent concentration, temperature, and treatment time on gravimetric recovery. The resulting models identified operating conditions associated with maximum predicted recovery within each experimental domain. Maximum experimental gravimetric recoveries of 42.7% and 57.7% were obtained for the acid and alkaline treatments, respectively. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA) were used to evaluate structural and thermal changes in the resulting materials. FTIR spectra showed reductions in bands associated with hemicellulose and lignin-related functionalities after chemical treatment. The Segal crystallinity index increased from 41.2% in untreated fibers to 52.7% and 63.8% in the materials obtained under the selected acid and alkaline treatment conditions, respectively. Thermal analysis further showed an increase in the maximum degradation temperature following chemical treatment. Collectively, the results demonstrate that the treatment conditions influenced both gravimetric recovery and the structural and thermal characteristics of the recovered materials. These findings support further investigation of C. palmata as a non-conventional lignocellulosic feedstock for cellulose-based polymer materials.