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چکیده
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Ozone is an environmentally- friendly oxidant that is widely used for industrial applications, such as water disinfection, air purification, and medical use [1]. Ozone that kills microorganisms, decomposes organic molecules, and removes unwanted components including coloration, cyanide, phenols, iron, and manganese. It can be used to disinfect portable water, food, surgical equipment, and sewage [1]. Ozonation was (removed) carried out for COD removal of water [2,3,5,7]. Additionally, ozone is safer than many other disinfectants because it decays to oxygen relatively quickly and leaves no harmful residuals. The efficiency for the oxygen → ozone conversion process (O2 + O° →O3) taking place during silent electric discharge (corona process) depends on several factors: oxygen source (O2or air); gas temperature and presence of impurities in the gaseous phase. The efficiency presented by most of the commercially available corona devices, using air as the O2 source, is l0.4 – 2.0 wt% and requires an “apparent” energy demand (where costs concerning gas refrigeration and heat exchange are not considered) of l14–28 Wh/g. Considering that nitrogen is not an inert gas inside the corona device, this experimental approach using air presents the environmental inconvenience of releasing strong pollutants such as NOx compounds and HNO3 into the atmosphere. Another commercially available technology for ozone generation is based on electrochemistry (water electrolysis: 3H2O→O3 + 6H+ + 6e–) [3]. This approach can be achieved by suitable choice of the anode material to have a high over potential for OER. In addition to, the material electrode in anode should have good conductance, high durability under drastic operating conditions, and particularly good electrocatalytic activity for ozone production. Different electrodes contain β-PbO2, Pt, Pt composites, boron-doped diamond, TiO2 thin films on Si/TiOx/Pt substrate, and Ti/Ni-Sb-SnO2 catalysts are among the materials that have been used for EOP.[1-5] In this work, a high-performance porous titanium oxide electrode (Ti/TiO2/Ni-Sb-SnO2) has been developed for electrochemical production of ozone. The Ti/TiO2 electrode was prepared using anodizing method at high voltage for forming a layer of porous TiO2 on the surface of Ti mesh, then followed by depositing a layer of Ni-Sb-SnO2 under deep eutectic solvent on the Ti/TiO2 surface. The deep eutectic solvent was used for electrodepositing, because its great effect on electrode performance. Ozone was electro generated from tap water on Ti/TiO2/ Ni-Sb-SnO2 electrodes at different operating conditions. Higher efficiency of O3 generation was obtained at 3 V in tap water (Fig. 1a).other electrode only with acidic electrolyte exponent to ozone generation but These electrodes were used in electrochemical ozone production (EOP) carried out during the electrolysis of electrolyte-free water in order to obtain an environmentally friendly technology for water treatment . Figure1b show the influence of COD removal as functions of the ozonation time.
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