Sample preparation for the measurement of BTEX photodegradation in air by pure catalyst

The precision measurement of VOC degradation obtained with a pure catalyst in heterogeneous gas-solid conditions is an important tool for photocatalyst research and development. The sample preparation is however a critical step in the measurement process. Typically sample preparation methods involve the deposition of the catalyst in powder from a water suspension. In this work were described and compared different sample preparation techniques based on deposition from a catalyst water suspension on a glass substrate using four dispersion techniques. All samples were tested for BTEX photocatalytic activity in air with a mixed flow photoreactor. The results demonstrates the needs to adopt a well defined and accurately implemented preparation procedure in studies where the precision of the resulting measurement is critical.