Active Carbon Microspheres / TiO₂ Composite Photocatalyst Prepared And Its Degradation Of Cationic Red Research

(ACMB)/TiO2 composite material prepared by steam thermal method was used as photocatalyst for the photodegradation of cationic red(X-GTL) wastewater. The as- prepared catalysts were characterized by scanning electron microscopy(SEM) and X-ray power diffraction(XRD). The conditions of X-GTL photodegradation were investigated. The optimal degradation condition of X-GTL was obtained though P-B and BBD experiment, in addition the degradation products of X-GTL were identified by ultraviolet-visible spectrum(UV-VIS), infrared spectrum(FI-IR), ion chromatography and liquid chromatography, and then the photodegredation pathway of X-GTL was obtained. Moreover, the photocatalytic mechanism of(ACMB)/TiO2 was analyzed via capturing free radicals experiment. The main research results are as follows:(1)The morphology and structure of catalyst were comprehensively characterized by SEM and XRD. The resulted showed that ACMB was of regular spherical morphology, perfect dispersion and mobility, and the diameter of ACMB was about 300 nanometer. The composite material not only kept the regular spherical morphology, but also nano-sized TiO2 particles homogenously encapsulated on the surface of the ACMB, and TiO2 was anatase crystal with high catalytic performance.(2)The influence which affect the X-GTL degradation such as the amount of catalyst,initial X-GTL concentration,pH and irradiation time was investigated. P-B and BBD experiment revealed that catalyst dosage, initial X-GTL concentration and pH were the main factors for removaling X-GTL, furthermore the removal rate of X-GTL was up to 98.65 % at the optical condition of 0.4 g/L catalyst, 50 mg/L initial X-GTL concentration, and pH was 4.(3)The degradation intermediate products and degradation path of X-TGL were investigated by UV-Vis, FT-IR, ion chromatography and liquid chromatography. The results showed that de-auxochrome was fall off firstly, then cleavage of azo bond was broken up, benzene of ring was opened following formation of small molecular organic acid. The main intermediate products of degradation were hydroquinone,phenol,3-chlorphenol,p-nitrophenol,nitrophenoland 3-chlornitrophenol.(4)The photocatalytic mechanism of the composite materials was discussed by analyzing, FT-IR and XRD of(ACMB)/TiO2 before and after, combing with the free radical capture experiments. Results indicated that O2- played a leading role in photocatalytic degradation and TiO2 still kept anatase after recycling for 5 times, thus the composite photocatalyst demonstrated good stability and high photocatalyst activity.