Germany Photooxidation purification of chlorinated hydrocarbon waste liquid

The German company Prosys (in Bremen, West Germany) has recently developed a photocatalytic process for the oxidation of organic pollutants such as phenol, chlorobenzene, chlorinated phenols and polychlorinated biphenyls that cannot be rapidly biodegraded. (polychlorinated biphenyls) etc. The commonly used photo-oxidation process requires the use of ultraviolet lamps and power supply facilities, while the German company's new process uses visible radiation from the sun for operation.
Method: First, the waste stream is continuously fed into a cylindrical reflux reactor. There, air sprayed from the lower end of the reactor upwards causes the liquid flow and catalyst to flow upward from the central circulation and descend along the reactor wall. The catalyst uses a chlorophyll-like dye and is supported on a spherical carrier. The dye absorbs visible light from the sun and transfers energy to the dissolved oxygen (from the air) so that more reactive O2 occurs, thereby oxidizing the contaminating material.
The company stated that in laboratory tests it was found that after a residence time of 40 minutes, the phenol concentration could be reduced from 650 mg/l to below the detection limit. The company is currently operating a medium-sized experimental plant of 0.5m3h-1 in the shipyard area of ​​Bremen in order to eliminate tributybtin (TBT) contaminants.