Blue dye degradation in an aqueous medium by a combined photocatalytic and bacterial biodegradation process

Abstract

This paper aimed at implementing a treatment system for polluted water with textile dyes, starting with a photocatalytic decomposition process using sunlight as a source of energy and continuing with a bacterial biodegradation process, in order to reach degradation percentages higher than those obtained using only one of the processes mentioned above. When water treatment with the dye in the combined system was over, an acute ecotoxicity test was performed to make sure that toxic metabolites were not produced due to biodegradation. Solophenyl Blue azoic dye, and Erionyl Blue and Terasil Blue anthraquinone dye-colored solutions were treated with the Pd/Al 80 Ce 10 Zr 10 catalyst in a solar collector for the photocatalytic process. On the other hand, the waste dye, which was obtained from photocatalysis with a bacterial consortium from polluted areas by metals and hydrocarbons in aerobic conditions, was inoculated for biodegradation. Biodegradation was obtained for the dyes after both processes as 90.91% for the Solophenyl Blue azoic dye, and 87.80% and 87.94%, respectively, for the Erionyl Blue and Terasil Blue anthraquinone dyes. After the degradation processes, it was proven, via an ecotoxicity test with Daphnia magna, that toxic metabolites had not been produced.

Comparison of Fe2TiO5/C photocatalysts synthesized via a nonhydrolytic sol–gel method and solid-state reaction method

“…The endothermic peak located at 879 C in the DSC curve is related with the phase transition, 28 owing to the rst occurrence of Fe 2 TiO 5 phase from 800 C to 900 C in the XRD patterns. The solid-state reaction is shown in formula (1). Moreover, it should be pointed out that some diffraction peaks indexed to hematite Fe 2 O 3 (JCPDS 33-0664) still exist at 1100 C as shown in Fig.…”

“…Since the 21 st century, environmental pollution, especially water pollution, has gradually become a major problem restricting the survival and development of human society. 1 Large amounts of dyes are discharged into rivers without any treatment in the textile industry, posing a great threat to water resources. 2 Much of the recent research has focused on the development of environmental remediation technologies/cleanness of water, 3,4 which is famous for advanced oxidation processes (AOPs).…”

Application of visible light active photocatalysis for water contaminants: A review

“…Textile wastewater often contains highly toxic and chemically stable organic compounds, including dyes, surfactants, oils, acid, alkali, solvents, and some metal salts, which are graded as one of the foremost pollutants in all industrial sectors (Ahmed et al, 2020;Kavil et al, 2020;Yusuff et al, 2020). Globally, it has been estimated that 280,000 tons of textile dyes alone are produced every year (Perez-Osorio et al, 2020). Without appropriate treatment, before discharge, it has the potential to cause serious environmental contamination for receiving aquatic ecosystems.…”