Preparation Of Modified Hemin Photocatalyst As Photocatalyst For Photocatalysis

Metalloporphyrins are senior photocatalytic oxidizers, which has the properties to activate molecular oxygen under mild conditions and catalytic degradate organic pollutants. But they are difficult to prepare and the yield is about 30 percent. Economic hemin is readily available raw material, by inducing ligand to its axial position or changing the central metal ion species after introducing electron withdrawing nitro substituent to the porphyrin ring meso-position can prepare two types of modified hemin. Its ability to absorb visible light and oxidation live can be improved through modifying.Meanwhile, the metal porphyrin molecules in aqueous prone to agglomeration, so the catalytic activity of the point can not be fully used. In this paper, modified hemin was bonded to a carrier having magnetic properties to prepare catalysts which are stability, high catalytic activity and ease of separation and recovery. And the catalysts were characterized by UVvisible spectrophotometer scanner, transmission electron microscopy, scanning electron microscope and thermo gravimetric.The catalyst performance evaluation showed that the catalyst can take full advantage of visible light, bisphenol A, p-nitrophenol and other organic matter all have degradation rate that higher than 90%, reactive red industrial wastewater can achieve 83.67% removal after 6h. After 5 recycling, the decline of degradation rate is only about 7%. Research results show that the catalyst has a practical value for the treatment of industrial wastewater containing biodegradable organic pollutants.Finally, UV-visible spectrophotometer scanner, high performance liquid chromatograph and gas chromatography-mass analyzer were used in catalytic degradation mechanism and process of in-depth research, the results show the modified heme photocatalyst prepared can make the organic matter broken down into smaller molecules and eventually mineralized to CO2 and H2 O without secondary pollution. Kinetic study of the catalytic reaction found that the reaction was first order reaction kinetics.