Complex membrane of cellulose and chitin nanocrystals with cationic guar gum for oil/water separation

Abstract

In an effort to develop a membrane system with low cost and easy fabrication process for oil/water separation, cellulose nanocrystals (CNC), chitin nanocrystals (ChiNC), and cationic guar gum (CGG) are used to prepare a complex membrane on top of a poly(ethylene terephthalate) (PET) nonwoven fabric via a vacuum filtration method. The interactions among CNC, ChiNC, and CGG complexation are discussed, and the functionalization of the PET nonwoven fabric with these polysaccharide derivatives provides a high rate of water absorption and permeability on applying pressure. The morphology and wettability studies demonstrate that the asprepared membrane has a porous structure and exhibits hydrophilic and underwater superoleophobic properties. The results of separation experiments show that the membrane can effectively separate oil/water emulsions with a relatively high flux and rejection ratio. This low-cost process can easily be scaled up to fabricate complex membranes for oil/water separation.

Complex Aerogels Generated from Nano-Polysaccharides and Its Derivatives for Oil–Water Separation

“…As was demonstrated in our previously reported study, mixing of polyelectrolytes with different charges is helpful in creating a complex membrane with porous structures [46,47]. In order to prepare the complex aerogel with a hierarchical porous structure, positively charged ChiNC was selected in this research to interact with the negatively charged TCNFs.…”

“…We have previously reported a method to prepare complex membranes with porous structures by mixing oppositely charged polyelectrolytes generated from polysaccharide materials, which exhibited good performances in separating oil–water emulsions [46,47]. In this research, we further explore this method to fabricate porous complex aerogels using polysaccharide-based nanomaterials and study their absorption performances.…”

Hydroxypropyl Guar/Cellulose Nanocrystal Film with Ionic Liquid and Anthocyanin for Real-Time and Visual Detection of NH3

“…Hydroxypropyl guar (HPG), containing plentiful active hydroxyl groups, is a derivative of guar gum comprised of a linear backbone of β-(1–4) d -mannose units containing α-(1–6) d -galactose units and hydroxypropyl groups as side chains. , HPG is suitable to fabricate biodegradable films owing to its low cost, renewability, good water solubility, excellent film-forming ability, and high viscosity. , However, the HPG film has low tensile strength and high hydrophilicity. HPG has been blended with cellulose nanocrystal (CNC) to improve the tensile strength and barrier properties, but the flexibility is significantly reduced. − Therefore, the flexibility of composite films can be improved by adding a plasticizer such as BmimCl.…”

Effect of Spacer Configuration on the Characteristics of FO Membranes: Alteration of Permeation Characteristics by Membrane Deformation and Concentration Polarization

“…The elastic modulus of the dried and wet CTA-ES2 membrane was 824.8 ± 167.47 and 531.8 ± 102.25 MPa, respectively. This is a common result that the mechanical strength is weakened because the structure loosens when the polymer or organic material is wet with water. , This drastic reduction of mechanical strength and inherent stiffness of CTA-ES2 membrane in wet state explains high susceptibility of CTA-ES2 membrane to hydraulic pressure (i.e., severe reduction of reflection coefficient under pressurization). The evidence of the structural vulnerability of CTA-ES2 membrane can also be found in visual observation.…”