ABSTRACT
The hydrodynamic behaviour of the fluidized bed photocatalytic reactor was such that the solid concentration distribution and gas hold-up of the reactor greatly influenced the adsorption and photodegradation of substrates in the reactor. Antibiotic pollutants, such as sulfamethoxazole (SMX) in wastewater, have been linked to antibiotic resistance, highlighting the need to remove these antibiotics from wastewater. Semiconductor photocatalysis using nanophase titanium dioxide and ultraviolet light from electric lamps have been widely used to photodegrade SMX. The reactor consisted of a glass section made of borosilicate glass screwed onto a bottom plastic section. Air was supplied to the reactors from a compressor through a common header from where gas lines channelled the air into the respective reactors. High solid–liquid and liquid–gas mass transfer rates are essential to achieve a high rate of adsorption and photodegradation. The optimum superficial air velocity found during adsorption and photodegradation was lower than the superficial air velocity obtained during hydrodynamic experiments.
