纳米氧化锰负载钛基电催化膜制备及处理含酚废水性能研究

Preparations of Nano-Manganite Loaded Titanium Electocatalytic Membrane Electrode for Phenolic Wastewater Treatment

以多孔钛膜为基膜,醋酸锰为锰源,采用溶胶-凝胶法制备出负载纳米氧化锰的钛基电催化膜(nano-MnO_x/Ti膜).运用X射线衍射(XRD)、X射线光电子能谱(XPS)、场发射扫描电子显微镜(FESEM)、循环伏安法(CV)、交流阻抗法(EIS)和计时电流法(CA)等测试手段,对MnO_x/Ti膜电极的微观形貌、晶型、电化学性能等进行表征.结果表明,所得催化剂是由直径为50 nm的γ-Mn O2和Mn2O3纳米棒所组成,且均匀分布于Ti膜上,负载催化剂后钛膜电极电化学性能和催化性能明显提高,催化剂与基体之间键合的形成提高其稳定性.以棒状nano-MnO_x/Ti膜电极为阳极构建电催化膜反应器(ECMR)处理含酚废水,当苯酚溶液浓度为10 mmol·L-1、电流密度为0.25 m A·cm-2、停留时间为15 min时,COD去除率可达95.1%.

Nano-manganese oxide loaded on titanium electrocatalytic membrane electrodes（nano-Mn Ox/Ti） were synthesized by sol-gel method using porous Ti membrane as a substrate and the manganese acetate as a raw material without releasing NOx. X-ray diffraction（XRD）, X-ray photoelectron spectroscopy（XPS） and Field-emission scanning electron microscopy（FESEM） were employed to characterize crystal form, valence state and surface morphology of nano-Mn Ox, respectively. Cyclic voltammetry（CV）,electrochemical impedance spectroscopy（EIS） and chronoamperometry（CA） were used to investigate the electrochemical properties of nano-Mn Oxelectrode. The results indicated that the Mn Oxcatalysts consisted of γ-Mn O2 and Mn2 O3 nanorods with the diameter of50 nm, which distributed uniformly on the Ti membrane. The electrochemical performance and catalytic performance of the membrane electrode improved obviously after the loading of the catalyst. The formation of chemical bond between Ti and Mn Oxled a good stability of Mn Ox/Ti membrane electrode. The electrocatalytic membrane reactor（ECMR） was assmblied by using nanorods the Mn Ox/Ti membrane as an anode and a stainless steel mesh as a cathode for the phenolic wastewater treatment（10 mmol·L-1）. It was found that the COD removal rate of ECMR was up to 95.1% at current density of 0.25 m A·cm-2 and residence time of 15 min.