Biomimetic fabrication of superhydrophobic loofah sponge: robust for highly efficient oil–water separation in harsh environments

Abstract

Oil/water separation has become an increasingly important field due to frequent industrial oily wastewater emission and crude oil spill accidents. Herein, we fabricate a robust superhydrophobic loofah sponge via a versatile, environmentally friendly, and low-cost dip coating strategy, which involves the modification of commercial loofah sponge with waterborne polyurea and fused SiO 2 nanoparticles without the modification of any toxic low-surface-energy compound. The as-prepared loofah sponge showed excellent superhydrophobic/superoleophilic properties and exhibited robustness for effective oil-water separation in extremely harsh environments (such as 1 M HCl, 1 M NaOH, saturated NaCl solution and hot water higher than 95 C) due to the remarkably high chemical stability. In addition, the as-prepared loofah sponge was capable of excellent anti-fouling, has self-cleaning ability and could act as the absorber for effective separation of surfactant-free oil-in-water emulsions. More importantly, the asprepared loofah sponge demonstrated remarkable robustness against strong sandpaper abrasion and finger wipes, while retaining its superhydrophobicity and efficient oil/water separation efficiency even after more than 50 abrasion cycles. This facile and green synthesis approach presented here has the advantage of large-scale fabrication of a multifunctional biomass-based adsorbent material as a promising candidate in anti-fouling, self-cleaning, and versatile water-oil separation.

Valorization of Activated Carbon as a Reusable Matrix for the Immobilization of Aspergillus oryzae Whole-Cells Expressing Fusarium heterosporum Lipase toward Biodiesel Synthesis

“…Fourier-transform infrared spectroscopy (FT-IR) was used in this study as well (Figure ) to further characterize surface chemistry modification of the matrix. The stretching at 1066 cm –1 are attributed to COC bonding from ethers that were present in the original carbon (Figure , AC and IAC) . The source of AC used may have provided an advantageous growth of proteins as ethers are prevalent in the buildup of carbohydrates and lignin in biocatalysts. , Vibrational occurrence at 1732 cm –1 is attributed to a CO carbonyl stretch. ,, The biocompatibility of activated carbon with the cells is confirmed with the characteristic interference at 2962 cm –1 .…”

Facile Synthesis of Hydrophobic Loofah‐Chitin Aerogel for Efficient Removal of Benzene and Toluene

“…A loofah sponge is a vascular bundle of the dried and mature fruit of Luffa cylindrica (L.) Roem , which exists in the forms of xylem and phloem [10] . It has a continuous, flexible, and interconnected three‐dimensional (3D) network structure and shows remarkable mechanical properties, hydrophilicity, and lipophilicity [11,12] . Nonetheless, its surface is rich in hydrophilic hydroxyl groups, limiting its application for organic pollutant adsorption.…”

“…[10] It has a continuous, flexible, and interconnected three-dimensional (3D) network structure and shows remarkable mechanical properties, hydrophilicity, and lipophilicity. [11,12] Nonetheless, its surface is rich in hydrophilic hydroxyl groups, limiting its application for organic pollutant adsorption. Surface chemical modification is required to alter its properties.…”

Facile Fabrication of Magnetic, Durable and Superhydrophobic Cotton for Efficient Oil/Water Separation

“…Since Jiang et al [6] innovatively proposed a straightforward, rapid, and economical method for the construction of steel mesh film with superhydrophobic/superhydrophilic coatings for oil/water separation, various superhydrophobic substrates have gained attention for their potential application in oil/water separation [7,8,9,10,11,12,13,14]. The common oil/water separation materials such as stainless steel [15,16,17], strainer [18,19,20,21], filter paper [22,23,24,25], foam polyurethane [26,27,28,29], fabrics [30,31,32,33,34,35,36] and aerogels [37,38,39] have been widely studied in recent years. There still exist limitations such as low absorption capacities or environmental incompatibility or complicated preparation process.…”