Posted by Jinpeng Wang, Beijing Technology and Business University (BTBU), China, and colleagues have developed porous hydrophobic chitosan-based sponges that were grafted with aminoethyl β-cyclodextrin, citronellal, and palmitic acid to optimize their properties as absorbents. The team first prepared sponges from chitosan, aminoethyl-β-cyclodextrin, and sodium phytate as a crosslinking agent. The resulting sponges were dipped in a citronellal solution and dried. Immersion in a palmitic acid solution and another drying step gave the desired functionalized sponges.
The modifications of the chitosan increase the material’s hydrophobicity and absorption properties, as well as the mechanical stability. The preparation is environmentally friendly and the sponges show good absorption capacities for n-hexane, trichloromethane, vacuum pump oil, and peanut oil. The material selectively removes, e.g., peanut oil or chloroform from water. It also shows good biodegradability. The sponge exhibited excellent absorption capacities for n-hexane, trichloromethane, vacuum pump oil, and peanut oil (47.9, 32.3, 32.6, and 32.2 g/g, respectively). The removal rate of oil was more than 80% (>26.2 g/g) after 10 absorption–desorption cycles.
Chenxi Wang, Chao Qiu, Chen Zhan, David Julian McClements, Yang Qin, Aiquan Jiao, Zhengyu Jin, Jinpeng Wang, Green Preparation of Robust Hydrophobic β-Cyclodextrin/Chitosan Sponges for Efficient Removal of Oil from Water, Langmuir 2021, 37, 49, 14380–14389
https://doi.org/10.1021/acs.langmuir.1c02299- Picture credit to chemistryviews.org