Optimization of the indole photodegradation on supported TiO2:: influences of temperature, concentration, TiO2 amount and flow rate

This work describes the photodegradation of aqueous indole solutions by using TiO2 supported on cellulose fibres. Four parameters were studied: the indole concentration; the TiO2 amount; the temperature and the flow rate. Central composite experimental design was used to determine the influences of the parameters on the indole degradation percentage. We demonstrate that in our experimental domain the quasi complete degradation of indole is in all cases reached and more interestingly that it is possible to find unique values of TiO2 amount and flow rate leading to optimised photodegradation of indole in the studied domains of temperature and indole concentration.