Water microbial disinfection via supported nAg/Kaolin in a fixed-bed reactor configuration

In this paper we have investigated and demonstrated the antimicrobial capabilities of nano-silver-4 wt%-kaolin (nAg-4-Kn) composite supported on borosilicate glass beads (BGB). Tests have been conducted in a fixed bed reactor on effluent from the secondary clarifier of a conventional wastewater trea...

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Bibliographic Details
Authors: Yıldız Ozer, Lütfiye, Yusuf, Ahmed, Uratani, Joao M., Cabal, Belén, Díaz, Luis A., Torrecillas, Ramón, Moya, J. S., Rodríguez, Jorge, Palmisano, Giovanni
Format: article
Status:Versión aceptada para publicación
Publication Date:2020
Country:España
Institution:Consejo Superior de Investigaciones Científicas (CSIC)
Repository:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/219265
Online Access:http://hdl.handle.net/10261/219265
Access Level:Open access
Keyword:Water microbial disinfection
Fixed-bed reactor
Kaolinite
Silver nanoparticle
Description
Summary:In this paper we have investigated and demonstrated the antimicrobial capabilities of nano-silver-4 wt%-kaolin (nAg-4-Kn) composite supported on borosilicate glass beads (BGB). Tests have been conducted in a fixed bed reactor on effluent from the secondary clarifier of a conventional wastewater treatment plant (WWTP) in Abu Dhabi, United Arab Emirates (UAE). The prepared BGB with immobilized nAg-4-Kn (nAg-4-Kn/BGB) were characterized using the RAMAN spectroscopy, TEM equipped with EDX and Focus Ion Beam Scanning Electron Microscope (FIB-SEM) techniques. The rate of disinfection was assessed through Luria-Bertani (LB)-agar plate cell counting technique. The results showed complete disinfection after few hours, which was preserved even after several days in repeated runs. The nAg-4-Kn/BGB was reused, demonstrating that the immobilization of nAg-4-Kn was stably achieved, and the activity and integrity of the composites on the BGB were preserved. First order disinfection kinetic constants were estimated to be 2.76 cm h−1 and 2.56 cm h−1 in two consecutive runs. Analyses of the beads after the experiments showed minor losses of nAg from the kaolin matrix thereby corroborating reusability of these materials.