Aerogel Materials For Photocatalytic Detoxification Of Cyanide Wastes In Water
Ultraviolet-irradiated titania-silica (TiO2-SiO 2) aerogels were used as photocatalysts to oxidize/degrade aqueous cyanide species to CO 2 and N 2. TiO2-SiO 2 aerogel photocatalysts were prepared by the sol-gel technique and supercritical drying. Three types of TiO2-SiO 2 aerogel were prepared with different SiO 2 contents (i.e., TiO 2 : SiO 2 molar ratio = 1 : 1.3, 1:2.6 and 1:3.9). It was observed that, with increased SiO 2 content, shrinkage and apparent density decreased and translucency increased. This resulted in higher photocatalytic activity for oxidation of CN in dilute solutions (1000 and 522 ppm) of ferric cyanide.
Aerogel Materials For Photocatalytic Detoxification Of Cyanide Wastes In Water
Ultraviolet-irradiated titania-silica (TiO2-SiO 2) aerogels were used as photocatalysts to oxidize/degrade aqueous cyanide species to CO 2 and N 2. TiO2-SiO 2 aerogel photocatalysts were prepared by the sol-gel technique and supercritical drying. Three types of TiO2-SiO 2 aerogel were prepared with different SiO 2 contents (i.e., TiO 2 : SiO 2 molar ratio = 1 : 1.3, 1:2.6 and 1:3.9). It was observed that, with increased SiO 2 content, shrinkage and apparent density decreased and translucency increased. This resulted in higher photocatalytic activity for oxidation of CN in dilute solutions (1000 and 522 ppm) of ferric cyanide.
Advanced Technologies In Water And Wastewater Treatment
The use of conventional water and wastewater treatment processes becomes increasingly challenged with the identification of more and more contaminants, rapid growth of population and industrial activities, and diminishing availability of water resources. Three emerging treatment technologies, including membrane filtration, advanced oxidation processes (AOPs), and UV irradiation, hold great promise to provide alternatives for better protection of public health and the environment and thus are reviewed in this paper.
Advanced Technologies In Water And Wastewater Treatment
The use of conventional water and wastewater treatment processes becomes increasingly challenged with the identification of more and more contaminants, rapid growth of population and industrial activities, and diminishing availability of water resources. Three emerging treatment technologies, including membrane filtration, advanced oxidation processes (AOPs), and UV irradiation, hold great promise to provide alternatives for better protection of public health and the environment and thus are reviewed in this paper.
A Study On Modeling And Simulation Of Capacitive Deionization Process For Wastewater Treatment
Wastewater treatment is an important issue in the era when water resources are continuously decreasing world-wide in the face of increasing demand. The need for cheap and energy efficient wastewater utilization technologies is thus drawing continuous attention.
A Study On Modeling And Simulation Of Capacitive Deionization Process For Wastewater Treatment
Wastewater treatment is an important issue in the era when water resources are continuously decreasing world-wide in the face of increasing demand. The need for cheap and energy efficient wastewater utilization technologies is thus drawing continuous attention.
A Study Of The Electrodeionization Process High-Purity Water Production With A RO/EDI System
An electrodeionization post-reverse osmosis (RO/EDI) system was developed for the continuous production of high-purity water without the use of chemicals. The study was carried out with a laboratory pilot. The ion-exchange membrane stack has eight cell-pairs of which four dilute compartments were filled with mixed-bed ion-exchange resins. The feed is tap water with a conductivity of about 400 ~ts/cm, and the RO permeate with a conductivity less than 20pas/cm. The EDI was achieved with a productivity of 201/h and a resistivity of 12-18M-Q-cm. In addition, the V-I and pH-I characteristics of the EDI process were studied. It indicates that there are differences between the ED and the EDI in the concentration polarization.
A Study Of The Electrodeionization Process High-Purity Water Production With A RO/EDI System
An electrodeionization post-reverse osmosis (RO/EDI) system was developed for the continuous production of high-purity water without the use of chemicals. The study was carried out with a laboratory pilot. The ion-exchange membrane stack has eight cell-pairs of which four dilute compartments were filled with mixed-bed ion-exchange resins. The feed is tap water with a conductivity of about 400 ~ts/cm, and the RO permeate with a conductivity less than 20pas/cm. The EDI was achieved with a productivity of 201/h and a resistivity of 12-18M-Q-cm. In addition, the V-I and pH-I characteristics of the EDI process were studied. It indicates that there are differences between the ED and the EDI in the concentration polarization.
A Carbon Electrode Fabricated Using A Poly(Vinylidene Fluoride) Binder Controlled The Faradaic Reaction Of Carbon Powder
A carbon electrode for capacitive deionization (CDI) was fabricated by casting a slurry that was a mixture of activated carbon powder (ACP) and poly(vinylidene fluoride) (PVdF) dissolved in di-methylacetamide (DMAc) on the current collector. Electrochemical properties and adsorption/desorption behaviors of the
carbon electrodes prepared with different PVdF contents (9–18 wt%) were characterized using cyclic voltammetry, chronoamperometry, and impedance spectroscopy methods. From the SEM images, carbon powders were coated with the PVdF binder and bound together. Capacitances of carbon electrodes were estimated in the range of 75.3–69.6 F/g, decreasing in tandem with PVdF contents, but the decrease was not significant. From cyclic voltammetric and chronoamperometricmeasurements, the electrochemical behaviors of the carbon electrodes were dependent not only on the electric double layer capacitance, but also on Faradaic reactions. However, Faradaic currents resulted from an electrochemical redox reaction of carbon surface controlled by the polymer binder. These results indicate that the electrochemical reaction on the carbon surface was suppressed due to the PVdF binder. 2010 The Korean Society of Industrial and Engineering Chemistry.
A Carbon Electrode Fabricated Using A Poly(Vinylidene Fluoride) Binder Controlled The Faradaic Reaction Of Carbon Powder
A carbon electrode for capacitive deionization (CDI) was fabricated by casting a slurry that was a mixture of activated carbon powder (ACP) and poly(vinylidene fluoride) (PVdF) dissolved in di-methylacetamide (DMAc) on the current collector. Electrochemical properties and adsorption/desorption behaviors of the
carbon electrodes prepared with different PVdF contents (9–18 wt%) were characterized using cyclic voltammetry, chronoamperometry, and impedance spectroscopy methods. From the SEM images, carbon powders were coated with the PVdF binder and bound together. Capacitances of carbon electrodes were estimated in the range of 75.3–69.6 F/g, decreasing in tandem with PVdF contents, but the decrease was not significant. From cyclic voltammetric and chronoamperometricmeasurements, the electrochemical behaviors of the carbon electrodes were dependent not only on the electric double layer capacitance, but also on Faradaic reactions. However, Faradaic currents resulted from an electrochemical redox reaction of carbon surface controlled by the polymer binder. These results indicate that the electrochemical reaction on the carbon surface was suppressed due to the PVdF binder. 2010 The Korean Society of Industrial and Engineering Chemistry.
