Degradation Effectiveness And Mechanism Of Fibrate Phamaceuticals By Silicate-based Microfiltration Membrane Catalytic Ozonation

Fibrates drugs are a class of fibric acid lipid-regulators drugs,which is by stimulating the activity of protease to accelerate the decomposition of lipoproteins and reduce the synthesis of lipids in the liver to achieve the purpose of lowering blood lipids.These substances in the surface water,groundwater are trace detection,detection in ng/L~?g/L at home and abroad,and which exposed to the environment will produce chronic toxic,and will bring harm to human health and the ecological environment in the long time.Therefore,it is necessary to study an efficient treatment to removal such pollutants and prevent the health of drinking water.In this paper,two kinds of fibrates drugs are selected,named bezafibrate(BZF)and gemfibrozil(GEM).At present,the removal methods of fibrates drugs are catalytic oxidation,photo-Fenton and photocatalytic method.In this study,the silicate-based micofiltration memmbrane was used to catalyze ozone to removal of BZF and GEM in water.The results with the removal efficiency and influencing factors under the catalytic ozonation were compared,finally,summarizing the advantage of the catalytic ozonation and concluding to the degradation path.In the laboratory,the removal effciency of catalytic oxidation of BZF was 95% and the removal effciency of GEM was nearly 100% when the initial concentration of ozone was 1mg/L and the initial concentration of BZF and GEM were 80?g/L respectively.The results of the study on the effects of ozone oxidation and catalytic oxidation of BZF and GEM showed the initial concentration of the target and the increase of ozone concentration had the greatest effect on the removal effciency.The results on the pH value of the solution showed the removal effciency of BZF and GEM under ozone oxidation was the highest at pH 8,the highest removal effciency was at pH 7 under the catalytic oxidation.When the effect of humic acid concentration was lower than 2mg/L,which promoted the removal of BZF by catalytic oxidation,and lower than 1mg/L,the catalytic oxidation of GEM was promoted.Although the catalytic oxidation of two types of fibrates drugs can not achieve complete mineralization,but compared to the ozone oxidation the removal effciency of TOC has increased by 10%.The products of BZF and GEM by two kinds of ozone oxidation process were identified by UPLC-MS/MS.The process of oxidizing BZF was on the two benzene rings.Catalytic Ozonation BZF products contain some small molecular acid,.The oxidation of GEM process is also the hydroxyl ring benzene ring,Moreover,the side chain of the carboxyl and carbon oxygen bond is also oxidation.Catalytic oxidation is different,after the hydroxylation on the benzene ring,oxidation continues to produce aldehydes,and the side chain is breaked to produce small molecule compounds.