Degradation Of Oily Wastewater By Coated Photocatalyst With Visible Light Response

The primary oil pollutant on the ocean was caused by leaking of oil form the shipwreck, prospecting and excavating of oil on the sea, subsidence of oil gas in the atmosphere, shipping maintenance industry and offshore industry or harbor contamination. The negative impacts of spill oils to the ecosystems of ocean or environment of sea surface were very serious and unexpected. Because naphthenic oils aromatic hydrocarbons are biodegradable materials, oily waste water has been extensive attention of researchers. Due to limitations presented in the conventional oil-bearing wastewater treatment method, in this study, we tried to deal with oily waste water by photocatalysis technology. To solve the problem of the low sunlight utilization rate of traditional light catalyst, a series of bismuth oxide photocatalyst were prepared. In order to solve the problems which the photocatalyst is difficult to separate, Bi2O3dopped Ce immobilized on ceramics or cenosphere were prepared to realize the recycling of the catalyst. Specific content is as follows:Bi2O3doped Ce immobilized on ceramics was prepared used ceramics as carriers and was characterized by XRD, FT-IR and DRS. The photocatalytic performance was investigated used oily wastewater as contaminants, and the influence of initial concentration on photocatalytic performance was also investigated. At the same time, the influence of calcination time on the structure and photocatalytic performance was studied. The results indicated that Bi2O3doped Ce was successfully immobilized on ceramics and existed in the form of β-Bi2O3、α-Bi2O3and CeO2, respectively. Sideband absorption wavelength of photocatalyst expanded to around590nm after Ce doped and the range of light absorption greatly expanded. Used BioO3doped Ce immobilized on ceramics as catalyst to degrade oily wastewater of100mg/L, the removal rate of oil could reach85%after irradiated for90min. High initial concentration was in favour of oil removal. Bi2O3doped Ce immobilized on ceramic calcinated at500℃for3h have the highest photocatalytic performance.Bi2O3doped Ce immobilized on cenosphere was prepared used ceramics as carriers and was characterized by SEM, XRD, FT-IR and DRS. The photocatalytic performance was investigated used oily wastewater as contaminants, and the influence of initial concentration on photocatalytic performance was also investigated. At the same time, the influence of calcination time on the structure and photocatalytic performance was studied. The results indicated that Bi2O3doped Ce was successfully immobilized on cenosphere and existed in the form of P-Bi2O3、α-Bi2O3and CeO2, respectively. Sideband absorption wavelength of photocatalyst expanded to around590nm after Ce doped and the range of light absorption greatly expanded. Used Bi2O3doped Ce immobilized on cenosphere as catalyst to degrade oily wastewater of100mg/L, the removal rate of oil could reach90%after irradiated for30min. Low initial concentration was in favour of oil removal. Bi2O3doped Ce immobilized on cenosphere calcinated at500℃for3h have the highest photocatalytic performance.