Preparation Of Modified TiO₂ Nanotube Arrays And Their Photoelectrocatalytic Degradation Of Polyacrylamide

Owing to the excellent water solubility and thickening ability, the application of polyacrylamide(HPAM) has been increasingly widespread in the tertiary oil recovery phase of oilfields. In order to enhance the oil recovery, the treated oilfield-produced water was reinjected into the oil layer, which can recyle crude oil from the water and realize the water cyclic utilization as well. However, the massive HPAM from the produced water has caused great damage on the environment along with the increasing amount of the water reinjection.There exist many problems such as the high cost, inefficiency and the secondary pollution in processing the the produced water presently. Therefore, it has become one of the most urgent matters to look for an effective, low cost and pollution free processing method for the sewage containing HPAM to realize continuous high yield of the oil field.Highly ordered honeycombed TiO2 nanotube arrays(TiO2 NTs) were produced via a two-step electrochemical anodic oxidation process in this paper. Using honeycombed TiO2 NTs as the anode, the advantages of photoelectrocatalysis were carried out by comparision on the HPAM degradation under UV-irradiation at room temperature. Effects of paramaters such as bias voltage, supporting electrolyte concentration, initial pH value and intensity of light source were also investigated to optimize the experimental conditions.For the defects of the low utilization rate of solar energy and high photogenerated charge recombination rate on the surface of TiO2 NTs, noble metal nanoparticles such as Au, Pt and Fe3+ were loaded onto the honeycombed hierarchical structured TiO2 NTs surface via methods of photoelectro-deposition process and simple impregnation method respectively. The modified TiO2 NTs were characterized by means of SEM, EDS, XRD, XPS, etc. Taking HPAM as the target degradation product, the optimum doping conditions were confirmed through the evaluation of photoelectrocatalytic performances of TiO2 NTs before and after decoration with different paramaters.The products of HPAM degradation were detected by the High Performance Liquid Chromatography(HPLC). Basing on the results of HPLC detection, the possible photoelectrocatalytic degradation mechanism of HPAM was speculated preliminarily...