Cellulose Nanofibers Derived Surface Coating in Enhancing the Dye Removal with Cellulosic Ultrafiltration Membrane

Abstract

Commercially available ultrafiltration membranes were coated with cellulose nanofibers (CNFs) produced from softwood pulp by a two-step process: a non-derivatizing DES treatment and a simple mechanical treatment (high-speed homogenization and sonification). The CNFs coating aimed at enhancement of the removal of methylene blue (MB) from water and was investigated at different concentrations of the coating, quantified in grams of CNFs per square meter of the membrane (1.3, 6.5, 13, and 19.5 g/m2). The pure water permeability (PWP) was unaffected up to the concentration of 6.5 g/m2 but the dye retention increased approximately 2.5-fold. Even higher improvement of MB removal, about 4-fold, was observed when 19.5 g/m2 were used, however, the pure water permeability also decreased by about 30%. In addition, it was proved that the coating can be removed and created again several times which shows that the concept could be used to improve the retention of organic compounds when high permeability membranes are used.

Electrospun Silica-Polyacrylonitrile Nanohybrids for Water Treatments

“…Many research groups have been working on fabricating PAN-based composite nan-ofibers [ 20 ]. Expanding on that, electrospinning can be utilized to encapsulate all kinds of molecules, such as small-size chemical molecules [ 21 , 22 ]; drugs [ 23 ]; proteins and peptides [ 24 ]; nutrition and nanoparticles in monolithic core-shell, tri-layer core-shell, and other complicated nanostructures. However, limited efforts have been devoted to the addition of inorganic particles in a polymeric solution for creating hybrid nanofibers, as well as their influence on the working processes and potential applications.…”