Precision measurement of BTEX depollution in air by photocatalytic building materials using a stirred flow reactor

The reliable measurement of the photocatalytic depollution in air at ambient concentration is a very important tool for the development of depolluting photocatalytic building materials and has important applications in both the research field and in the development of normalized test methods. In this work it is described an improved measurement method based on a stirred flow photoreactor that allows the direct measurement of the photocatalytic pollutants degradation of an artificial air stream containing aromatic compounds in trace. The method is applicable to the measurement of the catalytic depollution properties of pure catalyst or photocatalytic materials and is readily applicable to research studies and to standardized test procedures. The main method advantages comprise the operation in stable, steady state condition, the elimination of interferences due to parasitic pollutants adsorption on photocatalytic sample, the uniformity of the pollutant concentration on the catalytic surface and a very good flexibility in the selection of the operating conditions.