Zhou L, Xu Z. Ultralight, highly compressible, hydrophobic and anisotropic lamellar carbon aerogels from graphene/polyvinyl alcohol/cellulose nanofiber aerogel as oil removing absorbents.
J Hazard Mater 2020;
388:121804. [PMID:
31843408 DOI:
10.1016/j.jhazmat.2019.121804]
[Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 11/04/2019] [Accepted: 11/30/2019] [Indexed: 05/16/2023]
Abstract
In increasingly serious marine pollution environment, environmentally friendly low-density aerogels have become potential oil-water separation materials. However, many reported aerogels have the drawbacks of low oil absorption, poor compressibility and flexibility, which limit their application. Herein, we reported a compressible, anisotropic lamellar hydrophobic and lipophilic graphene/polyvinyl alcohol/cellulose nanofiber carbon aerogel (a-GPCCA) prepared by directional freeze-drying and carbonization processes. The synthetic ultralight a-GPCCA had low density (6.17 mg/cm3) and high porosity (99.61 %). Moreover, directional freeze-drying resulted in a lamellar interpenetrated three-dimensional porous structure, which endowed it with high adsorption capacity (155-288 times of its weight), good compressibility (95 % recovery after repeating 15 cycles at 50 % strain in parallel to the freezing direction) and recyclability (oil retention rate reached 88.8 % after 10 absorption-compression cycles). Furthermore, carbonization provided it with excellent thermal stability and hydrophobic properties, resulting in oil-water selectivity and combustion cyclicity (the oil absorption capacity was reduced by only 10.2 % after 10 absorption-combustion cycles). Therefore, the a-GPCCA obtained in this study possesses a promising potential in the field of treatment of offshore oil spills and domestic industrial wastewater.
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