A novel high gravity multi-concentric cylinder electrodes-rotating bed(MCCE-RB) was developed for the electrocatalytic degradation of phenol wastewater in order to enhance the mass transfer with the self-made RuO_2-Ir...A novel high gravity multi-concentric cylinder electrodes-rotating bed(MCCE-RB) was developed for the electrocatalytic degradation of phenol wastewater in order to enhance the mass transfer with the self-made RuO_2-IrO_2-SnO_2/Ti anodes. The influences of electric current density, inlet liquid circulation flowrate, high gravity factor, sodium chloride concentration,and initial pH value on phenol degradation efficiency were investigated, with the optimal operating conditions determined. The results showed that under the optimal operating conditions covering a current density of 35 mA/cm^2, an inlet liquid circulation flowrate of 48 L/h, a high gravity factor of 20, a sodium chloride concentration of 8.5 g/L, an initial pH value of 6.5, a reaction time of 100 min, and an initial phenol concentration of 500 mg/L, the efficiency for removal of phenol reached 99.7%, which was improved by 10.4% as compared to that achieved in the normal gravity field. The tendency regarding the change in efficiency for removal of phenol, total organic carbon(TOC), and chemical oxygen demand(COD)over time was studied. The intermediates and degradation pathway of phenol were deduced by high performance liquid chromatography(HPLC).展开更多
Both Ti foil and porous Ti were anodized in 0.5%HF and in ethylene glycol electrolyte containing 0.5%NH4F(mass fraction) separately. The results show that TiO2 nanotubes can be formed on Ti foil by both processes, whe...Both Ti foil and porous Ti were anodized in 0.5%HF and in ethylene glycol electrolyte containing 0.5%NH4F(mass fraction) separately. The results show that TiO2 nanotubes can be formed on Ti foil by both processes, whereas TiO2 nanotubes can be formed on porous Ti only in the second process. The overhigh current density led to the failure of the formation nanotubes on porous Ti in 0.5%HF electrolyte. TiO2 nanotubes were characterized by SEM and XRD. TiO2 nanotubes on porous Ti were thinner than those on Ti foil. Anatase was formed when TiO2 nanotubes were annealed at 400 °C and fully turned into rutile at 700 °C. To obtain good photodegradation, the optimal heat treatment temperature of TiO2 nanotubes was 450 °C. The porosity of the substrates influenced photodegradation properties. TiO2 nanotubes on porous Ti with 60% porosity had the best photodegradation.展开更多
基金financially supported by the Nature Science Foundation of China (Grant No.U1610106)the Nature Science Foundation of China (Grant No.21703208)
文摘A novel high gravity multi-concentric cylinder electrodes-rotating bed(MCCE-RB) was developed for the electrocatalytic degradation of phenol wastewater in order to enhance the mass transfer with the self-made RuO_2-IrO_2-SnO_2/Ti anodes. The influences of electric current density, inlet liquid circulation flowrate, high gravity factor, sodium chloride concentration,and initial pH value on phenol degradation efficiency were investigated, with the optimal operating conditions determined. The results showed that under the optimal operating conditions covering a current density of 35 mA/cm^2, an inlet liquid circulation flowrate of 48 L/h, a high gravity factor of 20, a sodium chloride concentration of 8.5 g/L, an initial pH value of 6.5, a reaction time of 100 min, and an initial phenol concentration of 500 mg/L, the efficiency for removal of phenol reached 99.7%, which was improved by 10.4% as compared to that achieved in the normal gravity field. The tendency regarding the change in efficiency for removal of phenol, total organic carbon(TOC), and chemical oxygen demand(COD)over time was studied. The intermediates and degradation pathway of phenol were deduced by high performance liquid chromatography(HPLC).
基金Project(1254G024)supported by the Young Core Instructor Foundation from Heilongjiang Educational Committee,ChinaProject(2012RFQXS113)supported by Scientific and Technological Innovation Talents of Harbin,China
文摘Both Ti foil and porous Ti were anodized in 0.5%HF and in ethylene glycol electrolyte containing 0.5%NH4F(mass fraction) separately. The results show that TiO2 nanotubes can be formed on Ti foil by both processes, whereas TiO2 nanotubes can be formed on porous Ti only in the second process. The overhigh current density led to the failure of the formation nanotubes on porous Ti in 0.5%HF electrolyte. TiO2 nanotubes were characterized by SEM and XRD. TiO2 nanotubes on porous Ti were thinner than those on Ti foil. Anatase was formed when TiO2 nanotubes were annealed at 400 °C and fully turned into rutile at 700 °C. To obtain good photodegradation, the optimal heat treatment temperature of TiO2 nanotubes was 450 °C. The porosity of the substrates influenced photodegradation properties. TiO2 nanotubes on porous Ti with 60% porosity had the best photodegradation.
