外加H_(2)O和H_(2)对氩气介质阻挡放电降解硫酰氟的影响

Effect of Adding H_(2)O and H_(2) on Degradation of Sulfuryl Fluoride by Argon Dielectric Barrier Discharge

硫酰氟(SO_(2)F_(2))是一种常用的熏蒸杀虫剂,然而其具有强温室效应,且目前缺乏针对性手段处理其废气,随意排放会对大气环境造成巨大危害。介质阻挡放电(dielectric barrier discharge,DBD)低温等离子体(non-themal plasma,NTP)技术是一种良好的气体污染物处理手段,而外加气体能有效改善其处理效果。为此基于NTP技术研究了外加H_(2)O和H_(2)对DBD降解SO_(2)F_(2)的影响。发现NTP协同活性气体降解SO_(2)F_(2)具有显著优势,外加H_(2)O和H_(2)均能够显著促进SO_(2)F_(2)降解,在该实验条件下,对于体积分数为2%的SO_(2)F_(2),外加H_(2)O或H_(2)体积分数为1%时,降解率分别达到最大值86.26%和80.29%,而过量的H_(2)O和H_(2)反而会限制降解;外加H_(2)O和H_(2)主要气体降解产物均为SO_(2)、SOF_(2)和HF,而外加H_(2)时还会生成固体S单质,H_(2)体积分数越高,S单质生成更为明显,有利于产物的回收处理,但H_(2)体积分数过量时少量S单质会进一步还原生成H_(2)S,不利于降解尾气处理。该研究结果能够为SO_(2)F_(2)废气无害化降解提供理论支撑。

Sulfuryl fluoride(SO_(2)F_(2)) is a commonly used fumigant pesticide.However,it has a strong greenhouse effect,and there is currently no pertinent means to treat its waste gas;meanwhile,random emissions will cause great harm to the atmosphere.Dielectric barrier discharge(DBD) low temperature plasma technology is a good method for gas pollutant treatment,and the addition of gas can effectively improve its treatment effect.In this paper,the effect of adding H_(2)O and H_(2)on degradation of SO_(2)F_(2)by DBD was investigated based on the non-themal plasma(NTP) technology.It is found that NTP has significant advantages in synergistic reactive gas degradation of SO_(2)F_(2).The addition of H_(2)O and H_(2)can significantly promote the degradation of SO_(2)F_(2).For 2% SO_(2)F_(2),when the concentration of H_(2)O or H_(2)is 1%,the degradation rate reaches the maximum value of 86.26%and 80.29%,respectively,while the excess H_(2)O and H_(2)will limit the degradation.With the addition of H_(2)O and H_(2),the main gas degradation products are SO_(2),SOF_(2),and HF,and the H_(2)system will also generate solid S element.The higher the H_(2)concentration is,the more obvious S elemental generation will be.In the meantime,a small amount of S element will be further reduced to form H_(2)S,which is not conducive to the degradation of exhaust gas treatment.The results of this study can provide theoretical support for the harmless degradation of SO_(2)F_(2)waste gas.