Use of modified cellulose-based sponges derived fromlignocellulosic waste for the removal of oilpollutants from water

Increasing industrial activities and oil spills have turned oil pollution into a significant environmental issue that poses a serious threat to aquatic ecosystems. The aim of this study is to develop cellulose-based, modified sponges from lignocellulosic wastes as a sustainable and low-cost solution, and to evaluate their oil removal performance from water. In this context, cellulose fibers obtained from renewable biomass sources such as agricultural and forestry industry wastes were converted into a three-dimensional, porous sponge structure using cryogenic freezing and lyophilization techniques. To enhance the surface properties of the produced sponges and convert their hydrophilic character into hydrophobic, an esterification reaction was carried out using stearoil klorür. Through this chemical modification, the water-repellent ability of the sponges was improved, enabling them to selectively adsorb oils. The structural, morphological, and chemical properties of the materials were thoroughly characterized using Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), contact angle measurements, and surface energy analyses. FTIR analyses confirmed the formation of new functional groups on the sponge surface as a result of the modification, while SEM images revealed the porous structure and uniform distribution of fibers. Contact angle tests showed that the modified sponges exhibited a water contact angle above 140°, indicating that the material had acquired superhydrophobic properties. The modified cellulose sponges were tested in adsorption experiments with various oils and chemicals such as motor oil, vegetable oil, diesel, and toluene. It was observed that the sponges could absorb oils in amounts ranging from 12 to 17 times their own weight, and this capacity was largely maintained in repeated use. Additionally, the sponges were subjected to up to ten regeneration cycles using mechanical squeezing and low-speed centrifugation, with adsorption efficiency remaining above 85%. These results demonstrate that cellulose sponges derived from lignocellulosic wastes are not only environmentally friendly and cost-effective but also high-performance oil sorbent materials. The findings suggest that such materials could serve as an effective and sustainable alternative to conventional methods in cleaning up oil spills and treating industrial wastewater.