Fabrication of cellulose-based aerogels from waste newspaper without any pretreatment and their use for absorbents

Cellulose-based aerogel (CBA) was prepared from waste newspaper (WNP) without any pretreatment using 1-allyl-3-methyimidazolium chloride (AmImCl) as a solvent via regeneration and an environmentally friendly freeze-drying method. After being treated with trimethylchlorosilane (TMCS) via a simple thermal chemical vapor deposition process, the resulting CBAs were rendered both hydrophobic and oleophilic. Successful silanization on the surface of the porous CBA was verified by a variety of techniques including scanning electron microscopy (SEM), energy-dispersive X-ray analysis (EDX), and water contact angle (WCA) measurements. As a result, the silane-coated, interconnected CBAs not only exhibited good absorption performance for oils (e.g., waste engine oil), but also showed absorption capacity for organic solvents such as chloroform (with a representative weight gain ranging from 11 to 22 times of their own dry weight), making them diversified absorbents for potential applications including sewage purification.