Preparation Of Magnetic Surface Imprinted Composite Photocatalyst And Its Selective Degradation Of Antibiotics

Due to antibiotic residues can easily lead to bacterial drug resistance, geneticmutations for humans and other animals produce carcinogenic teratogenic and damage,serious damage to the natural ecology, the environmental pollution.At present, the waterenvironmental pollution and harm caused by antibiotics has received extensive attention athome and abroad. Current wastewater treatment technology cannot effectively removedfrom the water, and semiconductor photocatalytic technology has simple operation, lowenergy consumption, wide applicable scope, no secondary pollution, high processingefficiency become the research hot spot. In recent years, the application of magneticnanoparticles in biosensors, material fast separation and enrichment of trace material hasbeen widely research. Molecular imprinting technology is one of target moleculespolymers with specific recognition ability of new technology. Molecularly imprintedpolymer with high selectivity, strong ability to resist bad environment, good stability, longlife and other characteristics, so in the chromatographic separation of chiral separation andanalysis, biomimetic sensors, chemical field show good application prospect.This thesis mainly includes the following three aspects of content:（1）Preparation by hydrothermal synthesis method, the particle size and dispersivity isgood magnetic ferroferric oxide nano microsphere.Fe₃O₄nanoparticles as carrier, magneticrespectively coated on the surface the inert SiO₂layer and the conductive layer of C, thenrespectively on the TiO₂and CdS semiconductor material coating, prepared withphotocatalytic activity, and magnetic separation characteristics of composite photocatalyst.The experimental result shows that the preparation of magnetic compositeTiO₂@SiO₂@Fe₃O₄photocatalyst has high degradation activity to enrofloxacinhydrochloride, CdS@C@Fe₃O₄also has very high degradation activity to ciprofloxacin,but there is no selectivity.（2）Selective degradation to enrofloxacin hydrochloride wastewater based on the surfaceof TiO₂@SiO₂@Fe₃O₄molecular imprinting technique TiO₂@SiO₂@Fe₃O₄as scaffold material, enrofloxacin hydrochloride （ENRH） astemplate molecule, with different functional monomer （methyl methacrylate, acrylamide,o-phenylendiamine, methyl acrylic acid,4-vinyl pyridine） and trimethylolpropane threeacrylate （TRIM） as crosslinking agent, azodiisobutyronitrile （AIBN） as initiator, and wasprepared by microwave polymerization of magnetic molecularly imprinted on the surfaceof TiO₂composite photocatalyst. Structure and characteristics of molecularly imprintedpolymer by X-ray diffraction （XRD）, transmission electron microscope （TEM） and Fourierinfrared spectroscopic analysis （FT-IR）, vibrating sample magnetometer （VSM） and so onwere characterized. Judge selectivity of catalyst with high performance liquidchromatography （HPLC）.The results showed that with the methyl methacrylate, templatemolecule and functional monomer ratio of1:8, preparation of magnetic molecularlyimprinted on the surface of composite photocatalyst TiO₂photocatalytic activity is best,and has good magnetic separation properties, high selectivity and reuse value.（3）Selective degradation to ciprofloxacin wastewater based on the surface ofCdS@C@Fe₃O₄the surface molecular imprinting techniqueCdS@C@Fe₃O₄as scaffold material, ciprofloxacin as template molecule, withdifferent functional monomer acrylamide, methyl acrylic acid, methyl methacrylate,pyrrole) was prepared by UV irradiation new type of magnetic composite polymer surfacemolecular imprinting CdS. Structure and characteristics of molecularly imprinted polymerby X-ray diffraction （XRD）, scanning electron microscope （SEM）, transmission electronmicroscope （TEM） and Fourier infrared spectroscopic analysis （FT-IR） were characterized.The results showed that the methyl acrylic acid, template molecule and functionalmonomer ratio is1:6,3h of polymerization synthesis of the surface of the magneticmolecularly imprinted composite photocatalyst optimal CdS, good photocatalytic activity,magnetic separation characteristics, higher selectivity and reuse value.