| In this paper,according to the current situation that the high-concentration chlorine ion wastewater degradation efficiency needs to be improved,the electrochemical oxidation technology and chlor-alkali industry anode technology were combined to prepare two new types of catalytic electrode materials,which were AC(activated carbon)supported Ru/Ti catalyst and AC supported Ru/Ti/Co catalyst,respectively.The catalytic performance of these two different electrode catalytic materials for degrade simulating high-concentration chloride ion wastewater was studied.And the chloride ions'removal rate was effectively improved by optimizing the process parameters of preparation and of electrochemical degradation.Based on the laboratory investigation,we chose desulfurization wastewater as an example to do the pilot experiment,and achieved a satisfied pilot result.Firstly,active carbon(AC)was activated by nitric acid soaking and ultrasonic treatment,and then AC-supported Ru/Ti oxide catalytic electrode material was prepared by a sol-gel method.This electrode was used as anode for the electrocatalytic oxidation degradation of high concentration chloride ion wastewater.The effects of pretreatment on activated carbon and Ru/Ti ratio,pH of simulated wastewater,and current density used for oxidative degradation of chloride ion wastewater were investigated.Electrodes were characterized by SEM,EDS,and BET.It was found that activated carbon had a larger mesopore area after activation treatment,and the dispersed catalytic material on it was more uniform;Treatment for simulated wastewater by Ru/Ti/AC anode showed greatly improved performance compared to AC electrode.The best preparation parameters were Ru/Ti ratio 3:7,calcination temperature 400?;calcination time 4h;pH=7.At this condition,120min electrocatalytic oxidation degradation treatment for simulated chloride wastewater,CaCl2 solution with Cl-concentration 12000mg/L,could obtained chlorine ion removal rate of 83.1%.Ruthenium is a kind of precious metal,its cost is expensive.On the basis of Ru/Ti/AC anode material,a part of Co was added instead of Ru,and a Ru/Ti/Co/AC composite electrode was prepared to study the electrode performance.The electrode particles were characterized by SEM,EDS and XRD.Co was successfully loaded on the catalytic material,and with the increase of Co content,the particle size of the material decreased.when the CaC12 solution with pH of 7 and Cl-concentration of 12000mg/L was treated by the electrocatalytic oxidation degradation for 120min,chloride ion degradation efficiency of the Ruo.2Ti0.7Co0.1-AC is greater than Ru0.3Ti0.7-AC electrode,91.25%of chloride ion removal was achieved.AST accelerated life test found that Ruo.2Ti0.7Co0.1-AC had better service life while keeping the highest chloride ion degradation efficiency than samples with other lanthanum titanium-cobalt ratios.According to the characteristics of desulfurization wastewater of the power plant,namely containing a large amount of chloride ions,a set of pilot plant for the treatment of chloride ion wastewater was self-esigned.The pilot test results show that for the initial desulfurization wastewater,with a chlorine ion concentration of 12818 mg/L,120 min electrochemical degradation treatment with Ru/Ti/Co oxide as the anode catalyst materialwith the current density is 400 mA/dm2,chlorine ion concentration could be reduced to 978.42mg/L and the removal rate was 92.37%.It reached the national first-class emission standard,and catalytic material coluld be replaced onetime in two months.The integrated treatment cost was about 1 yuan/m2,and the running cost was low.The shortcoming of the present technology has also been discovered through pilot tests.The ion-permeable membranes between the anode and cathode compartments in electrolyzers for desulphurization wastewater electrochemical treatment are susceptible to obstruction and failure.The engineering design and technical solutions for the shortcoming could be the main direction for this technology in the future. |
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