Amyloid fibril–bacterial cellulose nanohybrid membrane cartridge for efficient removal of heavy metal from industrial wastewater

Abstract

Worldwide, the harmful ion contamination of water has become a serious problem because of unregulated industry, energy production, and mining, which greatly increase the concentration of pollutants in water. The novel membranes through adsorbent self-assembly, such as protein amyloids, were explored for wastewater treatment. Herein, we report amyloid fibril (AF)-embedded bacterial cellulose nanohybrid membrane for efficient removal of heavy metal from industrial effluent. AFs are synthesized by heat treatment using bovine serum albumin and embedded with bacterial cellulose nanomembrane (BCN). The AF-embedded BCN (AF/BCN) was characterized using microscopy and spectroscopic methods. In addition, the well-ordered multi-layered AF/BCN filtration assembly was fabricated in the commercial cartridge and validated for the removal of heavy metals (Pb2+ and Hg2+) from wastewater and treatment of industrial wastewater sample containing heavy metals. Our multi-layered filtration assembly removed Hg+2 and Pb+2 with efficiency of 95 and 78.34%, respectively. A computational study using molecular docking has also been performed for the identification of metal entrapment sites. Moreover, our AF/BCN filtration assembly showed high regeneration capacity up to four cycles. The isotherm model also revealed a strong fit and good adsorption behaviour. This makes potential filtration assembly for low-cost, high-efficiency for the removal of HM from wastewater.