Study On The Photocatalytic Degradation Of Ibuprofen And Methylene Blue By BiOBr

Nonsteroid anti-inflammatory drugs (NSAIDs) belong to an important group of pharmaceutical, used as analgesics, with an estimated annual production of several kilotons. It is extensively used to treat tooth aches, headache, muscular aches, rheumatoid arthritis, backache, and reduce fevers. Though its concentration is very low in nature, it may present as potential risk to ecosystem and human health during its migration and transformation in the environment. At the same time, large volume of dye effluents were produced by textile industries, which were non-biodegradable and toxic. Those two effluents create severe environmental pollution problems if released into the aqueous phase. Methods mainly adopted today to treat those two effluents were biodegradation, adsorption, membrane filtration, photocatalytic degradation, Fenton oxidation, electrochemical oxidation and so on. In these methods, photocatalytic oxidation is one of the most promising technologies on organics removal, through which the organic compounds are effectively oxidized into benign and odorless constituents.Titanium dioxide (TiO2) has been found a wide application in cleanup of organic chemicals in water. However, TiO2can only be excited by ultraviolet irradiation with wavelength less than390nm, which covers only about4%of the solar spectrum. Due to this inherent limitation, the abundant solar energy (the visible light accounting for43%energy) can’t be utilized efficiently. In an attempt to efficiently harvest solar energy, intensive efforts have been devoted to development of novel visible-light-responsive photocatalysts.The3D mesoporous BiOBr microspheres via one-step solvothermal process without templates was synthesized in our research. The as-synthesized material was characterized by XRD, XPS, FESEM, TEM, UV-Vis, and nitrogen adsorption techniques. The results indicated that a well-crystallized high-purity BiOBr formed. BiOBr microspheres are constructed by nanoplates. The numerous nanoplates grew radically to form hierarchical microspheres with open porous structure. All the mesoporous diameters fall within the size range from7to30nm. The BET specific surface area and band gap of sample are7.69m2/g and2.64eV respectively. Absorption band red shift occurs.The photodegradation behavior of the nonsteroid anti-inflammatory drugs (NSAIDs) ibuprofen (IBP) in aqueous BiOBr suspension was investigated under simulated solar light irradiation. The photocatalytic activities of as prepared3D mesoporous BiOBr microspheres were excellent. IBP photodegradation intermediates were detected by GC/MS analyses and detailed reaction pathway was proposed. The photodegradation behavior of the cationic dyes (Methylene Blue) in aqueous BiOBr suspension was investigated. Effects of the conventional factors (pH, concentration of MB, additive amount of BiOBr) on the reaction were researched. It is important that we described the change of radicals by mathematical way. The relationship between photocatalytic activity and dissolved oxygen or pH was proposed. The luminous bacteria (Vibro qinghaiensis) toxicity evaluation showed the decrease of toxicity of the mother solution.