工艺参数对电氧化合成五氧化二氮的影响

采用RuO2-IrO2/Ti阳极和IrO2/Ti阴极、聚四氟乙烯隔膜和半连续板框式电解槽,在恒电压条件下研究了工艺参数对N2O4电氧化合成N2O5过程的影响。结果表明,阳极液中N2O4初始浓度低于45%时,电流效率随N2O4初始浓度增大而增大,比能随N2O4初始浓度增大而降低;当N2O4初始浓度超过45%时,两者均趋于恒定。阳极液中N2O4初始浓度对N2O5收率影响很小。电解液流量越高,电流效率和N2O5收率越高、比能越低。随反应温度增高,电流效率和N2O5收率先增大而后减少,比能的变化趋势则相反。适宜的反应条件为:阳极液中N2O4初始浓度45%、反应温度6℃、电解液流量63 mL.min-1。

Influence of Technological Parameters on Electro-oxidation of Tetroxide Dinitrogen to Form Pentoxide Dinitrogen

The electrosynthesis of pentoxide dinitrogen from tetroxide dinitrogen with RuO2-IrO2 coatings on the Ti substrate as anode and IrO2 coatings on the Ti substrate as cathode,and PTFE membrane as separator was carried out in a semi-continuous plate-and-frame electrolyzer at a constant voltage.Influences of technological parameters such as the initial concentration of tetroxide dinitrogen in anolyte solution,the flow rate of the anolyte and temperature on the electro-oxidation of tetroxide dinitrogen to form pentoxide dinitrogen were investigated.At an initial concentration of tetroxide dinitrogen in anolyte solution below 45% the current efficiency and specific energy improved with increasing the initial concentration of tetroxide dinitrogen in anolyte.At an initial concentration of tetroxide dinitrogen in anolyte solution above 45% the current efficiency tended to a constant value.However,there no significant change in the yield of pentoxide dinitrogen was found with increasing the initial concentration of tetroxide dinitrogen in anolyte solution.The higher the flow rate of the anolyte is,the higher the current efficiency and yield of pentoxide dinitrogen are and the lower the specific energy.There was an initial increase in both the current efficiency and yield of pentoxide dinitrogen with increasing temperature up to a maximum at 6 ℃,followed by a decrease in both the current efficiency and yield of pentoxide dinitrogen as temperature further increased.The tendency of the change in the specific energy was inverse with that both the current efficiency and yield of pentoxide dinitrogen.The optimized technological parameters for the electro-oxidation of tetroxide dinitrogen are initial concentration of tetroxide dinitrogen in anolyte solution of 45%,electrochemical reaction temperature of 6 ℃ and flow rate of the anolyte of 63 mL·min-1.