The use of a circulating upflow photocatalytic reactor for degradation, mineralization and kinetic study

A batch vertical reactor with a UV lamp, immersed symmetrically, and while receiving maximum emitted photons, without dead zone was used with the aid of circulating stream. To adjust the temperature, it was also jacketed to flow the external circulating stream of cooling water. The photocatalytic degradation of catechol, as a pollutant in wastewaters, was investigated. Catechol is a widely used intermediate that finds applications in a range of industries and it is significantly soluble in water. The well known TiO2 (anatase) catalyst was used. Data showed a maximum catechol conversion when catalyst concentration was about 10 mg L−1 and pH about 4.5. The efficiency of the photocatalytic degradation was determined with COD removal measurement of the samples. An empirical kinetic model was proposed for initial rate as a function of catechol concentration. This model includes the two competing observed decomposition paths, under the effects of photolysis and photocatlysis. A power law model and the Langmuir-Hinshelwood model were found to have good agreements with the data, respectively.

کلیدواژه ها:

Photodegradation ، UV/ TiO2 ، Catechol ، Environmental Pollutant ، Wastewater