UVC-Thermal Coupled Digestion without Oxidant for the Detection of Total Phosphorus

Abstract

In this paper, a catalyst-free and non-oxidant digestion method based on UVC and thermal coupled mechanism was developed for the digestion of total phosphorus (TP). Two kinds of digestion devices, “hamburg-type” and “screw-type”, were designed and compared to get higher digestion efficiency. Both of the two devices contain a quartz tube, UV light tubes, a flexible heating unit, UV light reflecting layer, and a temperature meter, etc. UVC light with the wavelength of 254nm is used to produce hydroxyl radicals to degrade TP into phosphate in water. Compared with the “hamburg-type” digestion device, the “screw-type” device exhibited a higher digestion rate. At the condition of 1 hour and 80°C, the digestion rate of 1mg/L (by weight of P) water sample can come to 96% by using the “screw-type” device.