Hydrophobic Collagen/Polyvinyl Alcohol/VCT Composite Aerogel for Efficient Oil Adsorption.

The development of effective oil adsorbents has attracted a great deal of attention due to the increasingly serious problem of oil pollution. A light and porous collagen (COL)/polyvinyl alcohol (PVA)/vanadium carbide (VCT) composite aerogel was synthesized using a simple method of blending, directional freezing, and drying. After modification with methyltriethoxysilane (MTMS) via chemical vapor deposition, the aerogel possessed an excellent hydrophobicity and its water contact angle reached 135°. The hydrophobic COL/PVA/VCT composite aerogel exhibits a porous structure with a specific surface area of 49 m/g. It also possesses prominent mechanical properties with an 80.5 kPa compressive stress at 70% strain, a low density (about 28 mg/cm), and outstanding thermal stability, demonstrating a 61.02% weight loss from 208 °C to 550 °C. Importantly, the hydrophobic COL/PVA/VCT aerogel exhibits a higher oil absorption capacity and stability, as well as a faster absorption rate, than the COL/PVA aerogel when tested with various oils. The hydrophobic COL/PVA/VCT aerogel has the capacity to adsorb 80 times its own weight of methylene chloride, with help from hydrophobic interactions, Van der Waals forces, intermolecular interactions, and capillary action. Compared with the pseudo first-order model, the pseudo second-order model is more suitable for oil adsorption kinetics. Therefore, the hydrophobic COL/PVA/VCT aerogel can be used as an environmentally friendly and efficient oil adsorbent.