RESUMEN

In the textile industry, membrane technology has been widely employed for the exclusion of direct dyes. In this research paper, firstly vapor grown carbon nanofibers (VGCNFs) were functionalized with carboxylates group via piranha oxidation, and then series of CA/PEO-PPO-PEO triblock copolymers were prepared by blending with varying weight percentages of modified VGCNFs and Zirconia (ZrO2). The structural morphologies of membranes were visualized by scanning electron microscope (SEM), atomic force microscopy (AFM) and transmission electron microscopy (TEM), which exhibits the dispersity of dual fillers in polymer matrix thus improving the microstructure of resultant membranes. The experimental data indicates that the modified VGCNF and ZrO2 nanoparticles were shown increase hydrophilic character. The direct dyes rejection were successfully after filler addition, which were 96% (for Direct Red), 99% (for Direct Blue) and 93% (for Direct Orange). The membranes showed a better antifouling property even after several washing cycles along with improved biofouling property, both of these properties showed a better membrane life. As an outcome, this research could have been a great potential to be used to treat dyes in textile industry.

RESUMEN

In this work, we developed hybrid membranes integrated with Nanocrystalline cellulose (NCC)/Gum Arabic (GuA) conjugates using crosslinked Poly (vinyl alcohol) (PVA) as a matrix phase with the addition of PEO-PPO-PEO block copolymer that insured pore formation. At first, the NCC was prepared from microcrystalline cellulose via acid hydrolysis process. The performance property of hybrid NCC/GuA was measured using boron removal. The results showed that the rejection capability enhanced as compared to the control membranes, especially at 0.1wt% of NCC the selectivity is up to 92.4% with the flux rate of 21.3L/m2.h. Moreover, the GuA in NCC/GuA conjugate significantly enhances the antibacterial activity by hindering the bacterial attachment to the surface as both of them carry the negative charge. Also by providing the active sites responsible for hydrogen bonding thus enhancing the hydrophilic character resulted in increased permeation flux rate. Therefore, the NCC/GuA conjugated membranes have great potentials for boron removal.

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RESUMEN

Inspired by the hydrophilic, biocompatible, adsorbent properties of chitosan. A simple, adaptable, green synthesis method was developed to prepare a thin film composite membranes using chitosan as a pore decorating material for the removal of anionic dye-Reactive orange 16 (RO-16). The hydrophilic chitosan was used to fill up the porous hydrophobic PVDF substrate, modified by MWCNTs. The dye rejection was carried out through the formation of a strong electrostatic interaction between the cationic group of chitosan surface and the anionic group of RO-16 dye. The dye molecules accumulate on the chitosan surface, thus promoting the higher retention rate. The TFC membranes were evaluated using dead filtration plant. It is found that the modified membranes showed RO-16 rejection up to 91% with optimum permeation flux of 170kgm-2h-1. Furthermore, the presence of chitosan on MWCNT/PVDF substrate provides a hydrophilic character thus decreasing the active sites available for foulant attachment which is confirmed by the fouling study. The CTAB foulant showed an increase in flux rate even after physical flushing. The modification procedure is performed under mild conditions, thus it is helpful to fabricate TFC membrane at a commercial scale.