Wood-Nanotechnology-Based Membrane for the Efficient Purification of Oil-in-Water Emulsions

Abstract

With increasing amounts of oily water discharged from industrial and domestic sources, purifying oily emulsions using effective and eco-friendly methods is of great significance. Although functional membranes with selective wettabilities have been extensively explored for the efficient purification of oil-inwater emulsions, the development of functional membranes that use green and inexpensive materials, are simple to fabricate, and are easy to scale up remains very challenging. Herein, we report a simple approach that uses biomass to prepare a membrane for the purification of emulsions. A simple top-down approach was used to partially remove lignin and hemicellulose fractions in wood sheets, resulting in a highly porous and flexible wood membrane. The obtained wood membrane shows excellent water-absorbing and underwater anti-oil adhesion properties due to the removal of the hydrophobic lignin. The wood membrane is durable and stable, thereby maintaining its selective wettability in harsh environments. Selective wetting properties along with a porous structure enable the wood membrane to purify surfactant-stabilized oil-in-water emulsions. Such a biomass-derived membrane, which is green, inexpensive, easy to fabricate, and scalable, along with its selective wettability and durability, shows great potential for use as a substitute for existing filter media in diverse industries.

Design, Development, and Outlook of Superwettability Membranes in Oil/Water Emulsions Separation

“…Hwang and co‐workers (2020) proposed a simple top‐down method to prepare a highly porous, flexible and super‐hydrophilic wood separation membrane by removing lignin and hemicellulose from wood. [ 234 ] Due to its superhydrophilicity‐underwater superoleophobicity combined with a microporous structure (less than 10 µm), resulting in good separation performance to emulsifiers stabilized oil‐in‐water emulsions and anti‐oil adhesion capacity. Although this green, low cost, degradable and naturally renewable biomass‐derived membrane, it has shown great potential to replace existing filter media in various industries.…”

Sustainable Wood Nanotechnologies for Wood Composites Processed by In-Situ Polymerization

“…Carbonization strategies followed by nanoparticle infiltration is used to provide electrical properties for energy-storage applications ( Chen C. et al, 2017 ; Luo et al, 2017 ; Song H. et al, 2018 ; Wang Y. et al, 2018 ; Tang et al, 2018 ; Zhu et al, 2018 ; Peng et al, 2019 ; Garemark et al, 2020 ). Since wood is designed for liquid transport in the tree stem, it can also be functionalized and serve as a membrane for water treatment or oil-water separation purposes ( Chen F. et al, 2017 ; Vidiella del Blanco et al, 2017 ; Fu et al, 2018a ; Guan et al, 2018 ; Vitas et al, 2018 ; Ding et al, 2020 ; Goldhahn et al, 2020 ; Kim et al, 2020 ).…”

Nano-biotechnology, an applicable approach for sustainable future

“…Wang et al have reported an interesting method of using gold nanoparticles (enriched by expanded genetic alphabet transcriptions) to increase the effectiveness of detecting the large natural or artificially synthesized RNAs through an RNA nano-based labeling Nanomaterials can be utilized in the form of membranes. Chemically or physically synthesized nanomembranes remarkably advance the conventional water purification techniques (Lohrasebi and Koslowski 2019;Kim et al 2020). Incorporating nanomembranes with bioreactors is the basis of the membrane bioreactor (MBR) technique, which is exploited in wastewater reclamation (Ma et al 2018).…”