Photocatalytic oxidation of azo dye solutions by impregnation of ZnO on fungi

• Published in: Biochemical engineering journal 2019-06, Vol.146, p.150-159
• Main Authors: Bouras, Hadj Daoud, Isik, Zelal, Bezirhan Arikan, Ezgi, Bouras, Noureddine, Chergui, Abdelmalek, Yatmaz, H. Cengiz, Dizge, Nadir
• Format: Article
• Language: English
• Subjects: Biosorbent; Dead fungi; Dye decolorization; Photocatalysis; ZnO
• ISSN: 1369-703X; 1873-295X
• DOI: 10.1016/j.bej.2019.03.014

[Display omitted] •AC and PG fungi were used as catalyst for photocatalytic oxidation.•ZnO powders were impregnated onto dead micro-fungi biosorbents.•100% BR18 and 76.2% RR180 decolorization levels were obtained by ZnO/AC, respectively.•100% BR18 and 73.7% RR180 decolorization levels were obtained by ZnO/PG, respectively. In this study, the semiconductor photocatalyst zinc oxide (ZnO) was used to impregnate on Aspergillus carbonarius (AC) and Penicillium glabrum (PG) fungi for photocatalytic oxidation of azo dye solutions. The photocatalytic decolorization of two textile dyes, Basic Red 18 (BR18) and Reactive Red 180 (RR180), was investigated and the impact of catalyst loading as well as initial dye concentration was systematically examined. Complete decolorization of BR18 was obtained by ZnO impregnated Aspergillus carbonarius (ZnO/AC) and Penicillium glabrum (ZnO/PG). The results also showed that the highest RR180 decolorization levels were 76.2% and 73.7% for ZnO/AC and ZnO/PG, respectively. The optimum catalyst loading was found to be 2 g/L. Catalyst reusability was also tested during five cycles and the bio-sorbent matrix (dead fungus) showed good stability after five reuse cycles. Photocatalytic decolorization of BR18 dye was much faster than RR180 dye, which we attributed to the electrostatic charge interaction between catalyst surface and dye molecules.