Photocatalytic oxidation is a promising technique for drinking water treatment

but is still in the phase of laboratory or small scale test at the moment.The inadequacy of the data of organics photodegradation at trace concentration and the difficulty in detecting trace organics are two outstanding problems.In this work

the clustering analysis method was used according to the structure of organics and the sequencing of their photodegradation rate.The Freundlich kinetics model was used to establish the relations between different scales of organics concentrations

from relatively high concentration to trace or even ultra trace concentration

because there are abundant data of photodegradation at a relatively high concentration.Starting from these data

the combination of clustering analysis

sequencing and kinetics model could show adequate information of the photodegradation at trace concentration

which is critical in the treatment of drinking water.