A Robust and Scalable Polydopamine/Bacterial Nanocellulose Hybrid Membrane for Efficient Wastewater Treatment

Abstract

Toxic heavy metal ions and organic pollutants are significant concerns in wastewater treatment. Here, we demonstrate a novel membrane composed of polydopamine (PDA) particles and bacterial nanocellulose (BNC), which can efficiently remove a variety of metal ions and organic dyes from contaminated water. The biocompatible and biodegradable PDA/BNC membrane is synthesized by in situ incorporation of PDA particles into BNC matrix during its bacteria-mediated growth. We show that the PDA/BNC membrane can effectively remove heavy metal ions such as lead and cadmium, and organic dyes as surrogate markers of organic pollutants such as rhodamine 6G (R6G), methylene blue (MB), and methyl orange (MO). The removal efficiencies of contaminants were tested separately or simultaneously via simple filtration at pH values ranging from 4 to 7. Furthermore, after simple washing with regeneration agents, the membrane can be reused multiple times without compromising its contaminant sorption ability and mechanical integrity. The new water treatment membrane introduced here is easy to fabricate, highly scalable, chemically stable, mechanically robust, and reusable, making it highly attractive for wastewater treatment.