Development of Cellulose-based Softwood Pulp Foam for the Removal of Microplastics

Abstract

Microplastics, generated from the decomposition of large plastic products, is one of the emerging pollutants that pose tremendous risks in the aquatic environment. Although previous studies have developed various strategies for the removal of microplastics, they were found to be non-renewable and costly. Cellulose provides green and sustainable approaches in water treatment systems as it is derived from plant sources making it biodegradable and biocompatible. In this study, two cellulose derivatives, microcrystalline cellulose (MCC) and nanocrystalline cellulose (NCC), were cationically and hydrophobically modified by grafting with (3-chloro-2-hydroxypropyl)dodecyldimethylammonium chloride (QUAB 342) to the particles. The modified systems were used in the development of softwood pulp foam for microplastic capture (WFQ342MCC-0.8 and WFQ342NCC-0.8 foams) The filtration performance of WFQ342MCC-0.8 foam was examined by analyzing its removal efficiency for polyethylene (PE) microplastics stabilized by sodium dodecyl benzene sulfonate (SDBS), polysorbate 80 (Tween 80), and hexadecyltrimethylammonium bromide (CTAB) surfactants (PE:SDBS, PE:CTAB, and PE:Tween80). The order of the removal efficiency during the filtration experiment was found to be PE:SDBS > PE:CTAB > PE:Tween80, respectively. Furthermore, WFQ342NCC-0.8 foam displayed removal efficiency of up to 99.8 %, as the addition of NCC improved the foam surface area with better microplastic capture.