CAPTURE OF MERCURY IN COMBUSTION SYSTEMS BY IN SITU-GENERATED TITANIAPARTICLES WITH UV IRRADIATION

In situ-generated sorbent titania particles with ultraviolet (UV) irra diation have been shown to be effective in capture of mercury in combu stor exhausts, Results of experiments conducted with the (1) sorbent p recursor only, (2) mercury only, (3) mercury and UV irradiation, and ( 4) mercury, titania, and UV irradiation are presented to elucidate the mechanisms of the capture process, Capture efficiencies (percentage o f Hg captured on the filter) as high as 96% were measured for mercury by titania with UV irradiation, A very high surface area titania sorbe nt was first formed, with mercury vapors condensing onto this surface, followed by photocatalytic oxidation and binding with the sorbent par ticles, The process has significant potential as a low-cost methodolog y for mercury control in practical combustion systems, Minimal retrofi tting may be necessary as conventional particulate control devices suc h as electrostatic precipitators have coronas with UV radiation presen t.