eprintid: 10189387
rev_number: 6
eprint_status: archive
userid: 699
dir: disk0/10/18/93/87
datestamp: 2024-03-21 16:04:57
lastmod: 2024-03-21 16:04:57
status_changed: 2024-03-21 16:04:57
type: article
metadata_visibility: show
sword_depositor: 699
creators_name: Bhuyan, MAH
creators_name: Busquets, R
creators_name: Campos, LC
creators_name: Luukkonen, T
title: Separation of microplastics from water using superhydrophobic silane-coupling-agent-modified geopolymer foam
ispublished: pub
divisions: UCL
divisions: B04
divisions: C05
divisions: F44
keywords: Geopolymer, Hydrophobicity, Microplastics, Silane coupling agent, Wastewater treatment
note: © 2024 The Author(s). Published by Elsevier B.V. under a Creative Commons license (http://creativecommons.org/licenses/by/4.0/).
abstract: Microplastics are a topical environmental problem that requires urgent solutions. They are ubiquitously present in various wastewaters and are discharged into aquatic environments because of difficulties in their removal. In this study, a novel filtration medium, superhydrophobic geopolymer foam, was prepared and investigated for the separation of microplastics from water. The foam was prepared using metakaolin, sodium silicate, sodium hydroxide, hydrogen peroxide, and Triton X-100 surfactant as raw materials and superhydrophobized with a silane coupling agent, triethoxy(octyl)silane. The purpose of the superhydrophobization was to improve the attachment of hydrophobic microplastic particles to the foam surface via chemical interactions. The modified geopolymer foam exhibited a water contact angle of 152°, and the presence of octyl chains on its surface was confirmed using Fourier transform infrared and X-ray photoelectron spectroscopies. When applied as a filter, the modified foam separated 53-63-µm sized polyethylene microspheres with ∼99 % removal efficiency, and no change in its separation efficiency was observed for ∼200 bed volumes of treated water. A comparison with an unmodified foam filter confirmed that the removal mechanism was not based on physical separation at higher flow rates, because the performance of the unmodified foam began to degrade after treating ∼5 bed volumes of wastewater. The performance of the modified foam was also validated with laundry washing effluents (particle size of microplastics varied roughly within 2–2000 μm), achieving ∼84 % separation efficiency for ∼50 bed volumes of wastewater. This study provides proof of concept of using superhydrophobic geopolymers as efficient, easy-to-prepare, and potentially low-cost separation media for microplastics from water effluents.
date: 2024-07-02
date_type: published
official_url: https://doi.org/10.1016/j.seppur.2024.126709
oa_status: green
full_text_type: pub
language: eng
primo: open
primo_central: open_green
verified: verified_manual
elements_id: 2257800
doi: 10.1016/j.seppur.2024.126709
lyricists_name: Campos, Luiza
lyricists_id: LCCAM91
actors_name: Kalinowski, Damian
actors_id: DKALI47
actors_role: owner
full_text_status: public
publication: Separation and Purification Technology
volume: 339
article_number: 126709
citation:        Bhuyan, MAH;    Busquets, R;    Campos, LC;    Luukkonen, T;      (2024)    Separation of microplastics from water using superhydrophobic silane-coupling-agent-modified geopolymer foam.                   Separation and Purification Technology , 339     , Article 126709.  10.1016/j.seppur.2024.126709 <https://doi.org/10.1016/j.seppur.2024.126709>.       Green open access   
 
document_url: https://discovery.ucl.ac.uk/id/eprint/10189387/1/Campos_Separation%20of%20microplastics%20from%20water%20using%20superhydrophobic%20silane-coupling-agent-modified%20geopolymer%20foam_VoR.pdf