Silver Nanoparticles Incorporated on Natural Clay as an Inhibitor against the New ISO SS Bacteria Isolated from Sewage Sludge, Involved in Malachite Green Dye Oxidation

Abstract

A facile, ecofriendly, and cost-effective method was developed to prepare a microporous material based on natural chemically modified bentonite with silver ions (BN-Ag0). This material presents a good catalytic activity against Malachite Green (MG) dye and bacteriostatic activity against a newly isolated bacterium from sewage sludge named hereafter “ISO SS” and Escherichia coli (E. coli). BN-Ag0 was characterized by the following methods: energy-dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET), Fourier-transform infrared (FTIR) spectroscopy, temperature programmed desorption (TPD) and X-ray Diffraction (XRD). The new bacterium ISO SS, was isolated using the technique of isolating a pure culture of anaerobically stabilized sludge. A mandatory characterization of ISO SS isolated strains from anaerobic stabilized sludge was performed in the process of identifying bacterial species. The cationic clay-based nanomaterial showed appreciable antibacterial activity against ISO SS, a Gram-negative bacterium. It also showed good activity against E. coli bacteria. As a catalyst in the catalytic ozonation of MG dye, BN-Ag0 significantly improves the oxidation time of the dye, due to its good adsorption and catalytic properties. The catalytic and antibacterial activities of the natural bentonite (BN) and of BN-Ag0 were examined using performant characterization techniques. The lifetime of the BN-Ag0 catalyst was also evaluated. Results obtained are expected to provide valuable findings for the preparation of a good microporous material with multiple functionalities.