Synergetic treatment of dye contaminated wastewater using microparticles functionalized with carbon nanotubes/titanium dioxide nanocomposites

Lian, Zheng; Wei, Chaohui; Gao, Bin; Yang, Xiaogang; Chan, Yue; Wang, Jing; Chen, George Zheng; Koh, Kai Seng; Shi, Yong; Yan, Yuying; Ren, Yong; He, Jun; Liu, Fu

Abstract

This journal is © The Royal Society of Chemistry. The highly efficient treatment of azo dye contaminated wastewater from the textile industry is an important but challenging problem. Herein, polydimethylsiloxane (PDMS) microparticles, incorporating multiple-walled carbon nanotubes/titanium dioxide (MWCNTs/TiO2) nanocomposites, were successfully synthesized to treat wastewater containing Rhodamine B (RhB) dyes in a synergetic approach, by combining sorption and photocatalytic degradation. The surfactant wrapping sol-gel method was applied to synthesize MWCNTs/TiO2 nanocomposites with TiO2 nanoparticles evenly distributed on the surface of the MWCNTs. The PDMS microparticles were fabricated with an oil-in-water (O/W) single emulsion template, using needle-based microfluidic devices. MWCNTs/TiO2 nanocomposites (at a weight ratio of 1%, and 2%, respectively) were mixed with the PDMS precursor as the dispersed phase, and an aqueous solution of polyvinyl alcohol (PVA) was used as the continuous phase. Highly monodispersed microparticles, with average diameters of 692.7 μm (Coefficient of Variation, CV = 0.74%) and 678.3 μm (CV = 1.04%), were formed at an applied flow rate of the dispersed and continuous phase of 30 and 200 μL min-1, respectively. The fabricated hybrid microparticles were employed for the treatment of RhB, involving a dark equilibrium for 5 hours and UV irradiation for 3 hours. The experimental conditions of applied PDMS type, mass loading amount, treatment duration, photodegradation kinetics, initial concentration of pollutants and environmental pH values were investigated in this work. The PDMS microparticles with 2 wt% MWCNTs/TiO2 nanocomposites can exhibit a removal efficiency of 85%. Remarkably, an efficiency of 70% can be retained after the microparticles have been recycled and reused for 3 cycles. The PDMS-MWCNTs/TiO2 microparticles possess a superior performance over conventional treatment approaches for dye contaminated wastewater, especially in recyclability and the prevention of secondary pollution. This work provides a feasible and eco-friendly route for developing an efficient and low-cost microfluidic method for treating complicated water environmental systems.

Citation

Lian, Z., Wei, C., Gao, B., Yang, X., Chan, Y., Wang, J., Chen, G. Z., Koh, K. S., Shi, Y., Yan, Y., Ren, Y., He, J., & Liu, F. (2020). Synergetic treatment of dye contaminated wastewater using microparticles functionalized with carbon nanotubes/titanium dioxide nanocomposites. RSC Advances, 10(16), 9210-9225. https://doi.org/10.1039/c9ra10899h

• Journal Article Type: Article
• Acceptance Date: Feb 23, 2020
• Online Publication Date: Mar 5, 2020
• Publication Date: Mar 5, 2020
• Deposit Date: Mar 7, 2020
• Publicly Available Date: Mar 9, 2020
• Journal: RSC Advances
• Electronic ISSN: 2046-2069
• Publisher: Royal Society of Chemistry
• Peer Reviewed: Peer Reviewed
• Volume: 10
• Issue: 16
• Pages: 9210-9225
• DOI: https://doi.org/10.1039/c9ra10899h
• Keywords: General Chemistry; General chemical engineering
• Public URL: https://nottingham-repository.worktribe.com/output/4106409
• Publisher URL: https://pubs.rsc.org/en/content/articlelanding/2020/RA/C9RA10899H#!divAbstract
• Additional Information: : This document is Similarity Check deposited; : Supplementary Information; : Chaohui Wei (ResearcherID); : George Zheng Chen (ORCID); : George Zheng Chen (ResearcherID); : Yong Ren (ORCID); : Jun He (ORCID); : Jun He (ResearcherID); : Fu Liu (ORCID); : Single-blind; : Received 25 December 2019; Accepted 23 February 2020; Version of Record published 5 March 2020