A sandwich-like structured superhydrophobic fabric for versatile and highly efficient emulsion separation

Abstract

Abstract The complexity and diversity of oily wastewater calls for versatile and efficient separation of emulsified oil/water mixtures. Herein, a facile method is applied to fabricate superhydrophobic cotton fabric for highly efficient separation of surfactant-stabilized oil/water mixtures. The fabric was prepared by repeated dip-coating of the pretreated cotton fabric in a dispersion containing multi-walled carbon nanotubes (CNTs) and epoxy resin E-44 (ER). This strategy could avoid not only the conventionally sophisticated fabrication process but also the usage of expensive low energy materials involved in preparing superhydrophobic materials. The modified cotton fabric exhibited remarkable separation of surfactant stabilized water-in-oil emulsion with a separation efficiency beyond 99%. Moreover, the superhydrophobic cotton fabric showed excellent chemical stability and mechanical durability. In addition, it could be applied to different types of emulsions prepared from various oils and emulsions with different water content, showcasing promising potential for practical water treatment.