Cardiff University | Prifysgol Caerdydd ORCA
Online Research @ Cardiff 
WelshClear Cookie - decide language by browser settings

Spirobifluorene-based polymers of intrinsic microporosity for the adsorption of methylene blue from wastewater: effect of surfactants

Al-Hetlani, Entesar, Amin, Mohamed O., Bezzu, C. Grazia and Carta, Mariolino 2020. Spirobifluorene-based polymers of intrinsic microporosity for the adsorption of methylene blue from wastewater: effect of surfactants. Royal Society Open Science 7 (9) , 200741. 10.1098/rsos.200741

[img]
Preview
PDF (Creative Commons Attribution License 4.0) - Published Version
Download (1MB) | Preview

Abstract

Owing to their high surface area and superior adsorption properties, spirobifluorene polymers of intrinsic microporosity (PIMs), namely PIM-SBF-Me (methyl) and PIM-SBF-tBu (tert-butyl), were used for the first time, to our knowledge, for the removal of methylene blue (MB) dye from wastewater. Spirobifluorene PIMs are known to have large surface area (can be up to 1100 m2 g−1) and have been previously used mainly for gas storage applications. Dispersion of the polymers in aqueous solution was challenging owing to their extreme hydrophobic nature leading to poor adsorption efficiency of MB. For this reason, cationic (cetyl-pyridinium chloride), anionic (sodium dodecyl sulfate; SDS) and non-ionic (Brij-35) surfactants were used and tested with the aim of enhancing the dispersion of the hydrophobic polymers in water and hence improving the adsorption efficiencies of the polymers. The effect of surfactant type and concentration were investigated. All surfactants offered a homogeneous dispersion of the polymers in the aqueous dye solution; however, the highest adsorption efficiency was obtained using an anionic surfactant (SDS) and this seems owing to the predominance of electrostatic interaction between its molecules and the positively charges dye molecules. Furthermore, the effect of polymer dosage and initial dye concentration on MB adsorption were also considered. The kinetic data for both polymers were well described by a pseudo-second-order model, while the Langmuir model better simulated the adsorption process of MB dye on PIM-SBF-Me and the Freundlich model was more suitable for PIM-SBF-tBu. Moreover, the maximum adsorption capacities recorded were 84.0 and 101.0 mg g−1 for PIM-SBF-Me and PIM-SBF-tBu, respectively. Reusability of both polymers was tested by performing three adsorption cycles and the results substantiate that both polymers can be effectively re-used with insignificant loss of their adsorption efficiency (®). These preliminary results suggested that incorporation of a surfactant to enhance the dispersion of hydrophobic polymers and adsorption of organic contaminants from wastewater is a simple and cost-effective approach that can be adapted for many other environmental applications.

Item Type: Article
Date Type: Publication
Status: Published
Schools: Chemistry
Publisher: Royal Society, The
ISSN: 2054-5703
Date of First Compliant Deposit: 14 October 2020
Date of Acceptance: 13 August 2020
Last Modified: 15 Oct 2020 12:45
URI: http://orca.cardiff.ac.uk/id/eprint/135594

Actions (repository staff only)

Edit Item Edit Item

Downloads

Downloads per month over past year

View more statistics