Informatics Publishing Limited

Doaa M. EL-Mekkawi ¹, Norhan Nady ², Nourelhoda A. Abdelwahab ³, Walied A. A. Mohamed ⁴, M. S. A. Abdel-Mottaleb ⁵

Affiliations
1 Physical Chemistry Department, National Research Centre (NRC), 33 Elbohouth Street, P.O. Box 12622, Dokki, Giza, EG
2 Polymeric Materials Research Department, Advanced Technology and New Materials Research Institute (ATNMRI), City of Scientific Research and Technological Applications (SRTA-City), New Borg El-Arab City, Alexandria 21934, EG
3 Polymers and Pigments Department, National Research Centre (NRC), 33 Elbohouth Street, P.O. Box 12622, Dokki, Giza, EG
4 Inorganic Chemistry Department, National Research Centre, 33 Elbohouth Street, P.O. Box 12622, Dokki, Giza, EG
5 Nano-Photochemistry and Solar Chemistry Department, Laboratory of Chemistry, Ain Shams University, Abbassia, 11566 Cairo, EG

Abstract

TiO₂ immobilized on polyethylene (PET) nonwoven sheet was used in the solar photocatalytic degradation of methylene blue (MB). TiO₂ Evonik Aeroxide P25 was used in this study. The amount of loaded TiO₂ on PET was approximately 24%. Immobilization of TiO₂ on PET was conducted by dip coating process followed by exposing to mild heat and pressure. TiO₂/PET sheets were wrapped on removable Teflon rods inside home-made bench-scale recirculating flow Compound Parabolic Concentrator (CPC) photoreactor prototype (platform 0.7 × 0.2 × 0.4m³). CPC photoreactor is made up of seven low iron borosilicate glass tubes connected in series. CPC reflectors are made of stainless steel 304. The prototype was mounted on a platform tilted at 30°N local latitude in Cairo. Acentrifugal pump was used to circulate water containing methylene blue (MB) dye inside the glass tubes. Efficient photocatalytic degradation of MB using TiO₂/PET was achieved upon the exposure to direct sunlight. Chemical oxygen demand (COD) analyses reveal the complete mineralization of MB. Durability of TiO₂/PET composite was also tested under sunlight irradiation. Results indicate only 6% reduction in the amount of TiO₂ after seven cycles. No significant change was observed for the physicochemical characteristics of TiO₂/PET after the successive irradiation processes.

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