摘要
采用电沉积法和涂刷热分解法制备钛基二氧化铅阳极(Ti/PbO2)、钛基锡锑金属氧化物涂层阳极(Ti/SnO2-Sb2O3)和带有锡锑金属氧化物中间层的改性钛基二氧化铅阳极(Ti/SnO2-Sb2O3/PbO2)。通过SEM及EDX分析,当涂液中溶质摩尔比n(Sn)∶n(Sb)=9∶1,溶剂为乙醇,烘干温度为110℃,烘干时间为10min,热分解温度为500℃,氧化时间为15 min,电流密度为20 mA/cm2时,制备出的Ti/SnO2-Sb2O3/PbO2阳极涂层表面晶体完整、致密均匀,且结晶比Ti/PbO2和Ti/SnO2-Sb2O3阳极明显细化,涂层不易脱落,电极的工作寿命更长;同时PbO2表层晶体结构的改善,不仅使电极具有更好的电化学活性,在酸性介质中也具有更好的耐腐蚀性。以3种尺寸稳定钛基金属氧化物涂层电极(Dimensionally Stable Anode,DSA)和石墨为阳极,不锈钢为阴极,采用DF120型均相阴离子交换膜,电渗析处理盐酸酸洗废水,240min时的铁回收率分别为75.1%、90.3%、91.7%和54.5%,耗电量分别为3.17 kW.h/kgFe、2.84 kW.h/kgFe、2.57 kW.h/kgFe、5.95kW.h/kgFe,DSA阳极的处理效果明显优于传统石墨阳极,Ti/SnO2-Sb2O3/PbO2阳极的处理效果最好。
The paper is dedicated to the discussion of the methods of preparing and characterizing Ti-Based Sn, Sb and Pb Oxide-Elec- trodes and their application to treating HC1 pickling sewage. As is known, the surface water on the ground has been seriously polluted by the untreated pickling sewage for its high concentration of Fe2 ＋ and H ＋ , particularly at high temperatures. Traditional treating methods have not been unable to achieve satisfactory results for it is only to neutralize the pickling sewage combined with solid-liquid separation. Besides, it was time-consuming. It is just for the above reasons that much has been talked about the method of zero-emission of the pick- ling sewage in recent years. In this paper, we would like to introduce the eletrodialysis method we have developed, in which we adopt the dimensionally stable anodes （ DSA）. With our method, the electrodes of Ti/SnO2 - Sb203, Ti/PbO2 and Ti/SnO2 - Sb203/PbO2 can be made through electrodeposition and thermal decomposition, respec- tively. The electrodes under discussion can be characterized in spec- tral ways. The results of our method by SEM and EDX indicate that the crystallization on the surface of the Ti/SnO2 - Sb2O3/PbO2 anode is integrated, uniformed, and much finer than those of Ti/SnO2 - Sb2O3 and Ti/PbO2 anode. The electrodes we have prepared are made under the following conditions ： Sn ： Sb = 9 ： 1 （ mole ratio） ; the solvent （ethanol; their drying temperature should be 110 ℃, drying time（ 10 min, the thermal decomposition temperature（500 ℃, oxidation time （15min, and, the current density is 20 mA/cm2. Our improvement of the crystal structure lies in that the Ti/SnO2 - Sb2O3/PbO2 anode enjoys a better conductivity and corrosion resistance in the acid medi- um. In the static eclctrodialysis system, the above said anodes can all be used for treating HC1 pickling sewage, respectively. In addition, the stainless steel cathode and the DF120 anion-exchange membrane can both be employed. The results of our experiments with the simu- lated sewage demonstrate that the Fe recovery rate can be as high as 75.1%, 90.3%, 91.7% and 54.5%, whose energy consumption only takes 3.17 kW h/kgFe, 2.84 kW h/kgFe, 2.57 kW h/kgFe, 5.95 kW h/kgFe, respectively. The experiments can be easily oper- ated under the conditions when the cell voltage = 10 V, reaction time = 240 min, pH of the cathode electrolyte solution = 2.50 - 3.00, Fe2 ＋ concentration of the cathode electrolyte solution = 1 000 - 1 300 mg/L, pH of the anode electrolyte solution = 3.00.
出处
《安全与环境学报》
CAS
CSCD
北大核心
2012年第6期53-56,共4页
Journal of Safety and Environment
关键词
环境工程学
电极
氧化物涂层
电渗析
酸洗废水
environmental engineering
electrode
metal oxide coat- ings
eletrodialysis
pickling sewage
