Optimized carboxymethyl cellulose (CMC) preparation from oil palm trunk (OPT) by response surface methodology (RSM)

Oil Palm Trunks (OPT), a significant waste, are utilized in this study as a source of cellulose for carboxymethyl cellulose (CMC) synthesis. The experiment design for synthesizing and optimizing CMC from OPT were investigated using Box-Behnken Design (BBD) as a reference in Response Surface Methodology (RSM). The process starts with the isolation of cellulose through pulping, washing and bleaching. Then, CMC synthesis is carried out in different sodium hydroxide concentrations (10-40 w/v%), different temperatures (45-75 °C) and different reaction times (1-4 h). Optimum conditions of 25.33 w/v% of NaOH, temperature of 62.66 °C and 2.54 h reaction time yielded a degree of substitution (DS) of 1.45. The yield was determined to be 91.72 wt% with a purity of 21.14 wt%. The optimum condition's responses validated experimentally presented an overall percentage difference below 5 %, indicating an acceptable prediction. In terms of characterization, the XRD analysis revealed a significant reduction in crystallinity, while the FE-SEM morphology and FTIR spectra respectively confirmed structural transition to CMC and the successful incorporation of carboxymethyl groups. Although the synthesized CMC exhibited a relatively high degree of substitution and yield, the purity achieved highlights opportunities for further refinement through advanced purification strategies. The findings demonstrate the feasibility of utilizing OPT as a sustainable source for high-value CMC production, with potential future improvements to enhance material quality and broaden application prospects.