Biomass-derived oriented neurovascular network-like superhydrophobic aerogel as robust and recyclable oil droplets captor for versatile oil/water separation

J Hazard Mater. 2022 Feb 15;424(Pt B):127393. doi: 10.1016/j.jhazmat.2021.127393. Epub 2021 Oct 1.

Abstract

Using tubular kapok fibers (KF) and sodium alginate (SA) as the natural building block, we put forward a novel oriented neurovascular network-like superhydrophobic aerogel with robust dry and wet compression resilience by directional freeze-drying and chemical vapor deposition. In the block, SA forms aligned channel structures providing space for rapid oil transmission, while KF serves as vascular-like capillaries acting as instant "tentacle" to capture the tiny oil droplets in water, facilitating fascinating oil capture efficiency for versatile oil/water separation, The aerogel after dry and wet compression (under a strain of 60%) can recover 96.0% and 97.3% its original, respectively, facilitating stable oil recovery (81.1-89.8%) by squeezing, high separation efficiency (99.04-99.64%) and permeation flux separating oil contaminants from water. A pump-supported experiment shows the aerogel efficiently collecting oil contaminants from the water's surface and bottom by 11503-25611 L·m-2·h-1. Particularly, the aerogel as robust oil droplets captor facilely achieves isolation of 99.39-99.68% emulsified oils from oil/water emulsions by novel oil trapping mechanism which simply involves exerting kinetic energy on emulsified oils through repeated oscillation, potentially indicating a simple and efficient alternative to membrane-based oily wastewater remediation via filtration.

Keywords: Compressibility; Emulsion purification; Kapok fiber; Oil/Water mixture separation; Superhydrophobic aerogel.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biomass
  • Emulsions
  • Hydrophobic and Hydrophilic Interactions
  • Oils*
  • Wastewater*

Substances

  • Emulsions
  • Oils
  • Waste Water