Highly Charged Cellulose Nanocrystals Applied as A Water Treatment Flocculant

• Main Authors: Dana Morantes, Efrén Muñoz, Doron Kam, Oded Shoseyov
• Format: Article
• Language: English
• Published: MDPI AG 2019-02-01
• Series: Nanomaterials
• Subjects: nanocellulose; surface modification; quaternary agent; flocculation
• Online Access: https://www.mdpi.com/2079-4991/9/2/272

Various cellulosic materials have replaced petroleum-derived polymers, offering natural and sustainable alternatives. Among them, cellulose nanocrystals (CNC) feature an easily modifiable surface, enabling the exploration of a wide spectrum of applications. In this work, the quaternary agent 3-chloro-2-hydroxypropyltrimethylammonium chloride (CHPTAC) was used as a cationic graft on CNCs, to form a novel water treatment flocculant. The resulting material was chemically and structurally characterized by the determination of Zeta potential; degree of substitution by elemental analysis; hydrodynamic size by dynamic light scattering (DLS) and infrared spectroscopy with Fourier Transform Infrared (FT-IR); and X-ray diffraction (XRD). The flocculation capacity of cationic cellulose nanocrystals (CNC-EPTMAC) was evaluated in a jar test filled with an 0.25 wt.% silica (SiO2) suspension. CNC-EPTMAC proved to be an effective water treatment flocculant, reducing turbidity by up to 99.7% at a concentration of only 2 ppm. This work demonstrates a natural and environmentally sustainable alternative to homologous commercial flocculants.