  Photocatalysis is often used in air purification. Photocatalytic degradation
od VOC's has been investigated in a number of devices. An optimisation of this
process requires a chracterisation of the reactor : in a first step the gas
flow behaviour has to be studied (plug flow, CSTR,...) by RTD analysis; then,
chemical kinetics have to be determined as a function ot the relevant
parameters (space time, relative humidity, concentrations, etc). All the data
collected lead to a reliable design of the equipment.
