A superhydrophobic CNF/PDA composite membrane has been developed to revolutionize oily wastewater treatment for achieving high efficiency, cost-effectiveness, and environmental sustainability. Inspired by the adhesive properties of mussels and the self-cleaning mechanism of lotus leaves, this innovative material is fabricated through a novel lyophilization and spray modification process using cellulose nanofibers (CNF), dopamine hydrochloride (DA), and octadecylamine (ODA). The membrane is synthesized via an aerobic, weakly alkaline self-polymerization process, which facilitates the formation of robust covalent and non-covalent bonds between the catecholamine structure of DA and CNF. ODA is integrated through hydrogen bonding and Schiff base reactions with polydopamine (PDA), enhancing structural stability. The resulting membrane demonstrates a tensile strength of 2.9 MPa, alongside exceptional separation efficiency (98.5 %) and flux rates (3745 L·m −2 ·h −1 ). Even after five consecutive water-in-oil (W/O) emulsion separation cycles, a separation efficiency exceeding 91.8 % is maintained, with hydrophobicity and structural integrity preserved. Durability tests confirm its robustness, with 98.5 % of initial capacity retained after ten adsorption-desorption cycles. The membrane's porous architecture and photothermal brown-black hue synergistically boost light-to-heat conversion, facilitating swift thermal response and efficient high-viscosity oil uptake. This demonstrates viable applications as a sustainable solution for oily wastewater treatment, promoting greener industrial application.
Removing oil pollution from seawater prior to its desalination helps in saving time and cost. In this study, a novel superhydrophobic cotton fabric with photothermal effect and self-cleaning property was prepared via the incorporation of Fe 3+ -polydopamine (PDA) coating and carbon nanotubes (CNTs) on the fabric surface (termed as CF@PDA/CNT), followed by the grafting of (3-glycidyloxypropyl)trimethoxysilane (GPTMS) and octadecylamine (ODA) (termed as the CF@PDA/CNT-GPTMS-ODA). CF@PDA/CNT exhibits good desalination with photothermal conversion capability on the high-salinity water (evaporation rate > 1.11 kg/(m 2 ⋅h)), providing an effective basis for the preparation of the photothermal-assisted oil–water separator (CF@PDA/CNT-GPTMS-ODA), with which the crude oil permeation time was improved from 58 s without light to only 9 s with light, showing the pronounced contribution of the photothermal effect on the oil permeation. In addition, CF@PDA/CNT-GPTMS-ODA used in the form of oil skimmer and underwater oil absorbent demonstrates excellent oil–water separation performance (separation efficiency > 97 %). Notably, the fabric can isolate various oil phases from both pure water and simulated seawater, with separation efficiencies exceeding 97 %. This novel material offers a promising solution for addressing complex water pollution issues and introduces a potential approach for integrating photothermal conversion effect into the field of oil–water separation.
危险品化学品经营许可证（带存储）