Silane and fluorine free facile hydrophobicization of water hyacinth biomass for oil-water separations

Shruti Bajpai; Parag R Nemade

doi:10.1016/j.chemosphere.2024.142164

Silane and fluorine free facile hydrophobicization of water hyacinth biomass for oil-water separations

Chemosphere. 2024 Apr 27:358:142164. doi: 10.1016/j.chemosphere.2024.142164. Online ahead of print.

Authors

Shruti Bajpai¹, Parag R Nemade²

Affiliations

¹ Institute of Chemical Technology Mumbai, Marathwada Campus, Jalna, 431 203, India.
² Institute of Chemical Technology Mumbai, Marathwada Campus, Jalna, 431 203, India; Department of Chemical Engineering, Institute of Chemical Technology, Mumbai, 400 019, India. Electronic address: pr.nemade@ictmumbai.edu.in.

PMID: 38685326
DOI: 10.1016/j.chemosphere.2024.142164

Abstract

As the adverse effects of using plastics and perfluorinated alkyl substances become more apparent, there is a growing need for sustainable hydrophobic products. Cellulose and its derivatives are the most abundant and widely used polymers, and cellulose-based products have great potential in industries where plastics and other hydrophobic polymers are used, such as stain-resistant fabrics, food packaging, and oil-water separation applications. In this study, we extracted cellulose from water hyacinth (WH) biomass, known for its negative environmental impact, and converted it into hydrophobic cellulose. This addresses the issue of managing WH waste and creating an environmentally friendly hydrophobic material. Initially, aldehyde groups were introduced through oxidation with periodate, followed by direct octadecyl amine (ODA) grafting onto dialdehyde cellulose (DAC) via a Schiff base condensation. The resulting ODA modified cellulose (ODA-C) was dispersed in ethanol and used to coat various materials, including cotton fabric, cellulose filter paper, and packaging paper. The modified materials showed excellent hydrophobicity as measured by their water contact angles (WCAs), and the application of the coating was demonstrated for oil-water separation, stain-resistant hydrophobic fabric, and paper-based packaging materials. FTIR, XRD, and WCA analysis confirmed the successful modification of cellulose. A high separation efficiency of 99% was achieved for diesel/water separation using modified filter paper (MoFP), under gravity. On application of the coating, cotton fabric became hydrophobic and resisted staining from dye, and paper-based packaging materials became more robust by becoming water-resistant. Overall, the facile synthesis, low cost, high efficiency, and use of environmentally friendly sustainable materials make this a promising strategy for hydrophobically modifying surfaces for a wide range of applications while reducing the menace of water hyacinth.

Keywords: Dialdehyde cellulose; Hydrophobic paper; Octadecylamine; Oil/water separation; Self-cleaning fabric; Water hyacinth.