Optimizing the synthesis conditions of aerogels based on cellulose fiber extracted from rambutan peel using response surface methodology

A cellulose-based aerogel has been synthesized from rambutan peel to mitigate environmental pollution caused by agricultural waste, rendering it an eco-friendly material with potential applications in oil spill remediation as well as enhancing the value of this fruit. The objective of this study was to extract cellulose from rambutan peel using chlorination and alkalization processes, followed by optimizing the synthesis conditions of cellulose-based aerogels from rambutan peel through experimental designs to improve oil removal efficiency. In this research, cellulose-based aerogel material was synthesized using the sol-gel method, utilizing waste from rambutan peel as the substrate and polyvinyl alcohol as the cross-linking agent, followed by freeze-drying. A central composite design with 30 different experimental setups was employed to investigate the influence of cellulose content (1.0–2.0%), cross-linking agent (polyvinyl alcohol) content (0.1–0.3%), ultrasonic time (5–15 min), and ultrasonic power (100–300W) on the oil adsorption capacity (g/g) of cellulose-based aerogels from rambutan peel. The research findings demonstrated successful extraction of cellulose from rambutan peel through chlorination, followed by softening with 17.5% (w/v) sodium hydroxide. Response surface plots indicated that maximizing the cellulose component could lead to a maximum diesel oil adsorption capacity of up to 52.301 g/g. Cellulose-based aerogel exhibits ultra-lightweight properties (0.027±0.002 g/cm3), high porosity (97.88±0.19), hydrophobicity (water contact angle of 152.7°), and superior oil selective adsorption compared to several commercially available materials in the market, demonstrating promising potential for application in treating oil-contaminated water in real-world scenarios.