化学学报 ›› 2019, Vol. 77 ›› Issue (2): 160-165.DOI: 10.6023/A18090401 上一篇    下一篇

研究论文

NH3与Cl2γ-Al2O3颗粒物表面的非均相反应

唐思群a,b, 马玲玲a, 罗敏a, 张朝晖c, 邱烨c, 冯烁c, 夏传琴b, 金永东b, 徐殿斗a   

  1. a 中国科学院高能物理研究所核技术应用研究中心 北京 100049;
    b 四川大学化学学院 成都 610064;
    c 北京出入境检验检疫局检验检疫技术中心 北京 100026
  • 投稿日期:2018-09-25 发布日期:2018-12-05
  • 通讯作者: 马玲玲,E-mail:malingling@ihep.ac.cn;徐殿斗,E-mail:xudd@ihep.ac.cn E-mail:malingling@ihep.ac.cn;xudd@ihep.ac.cn
  • 基金资助:

    项目受国家自然科学基金(Nos.U1832212,11405184,11575210,91643206)和中科院重点部署项目(No.ZDRW-CN-2018-1)资助.

Heterogeneous Reaction of NH3 and Cl2 on the Surface of γ-Al2O3 Particles

Tang Siquna,b, Ma Linglinga, Luo Mina, Zhang Zhaohuic, Qiu Yec, Feng Shuoc, Xia Chuanqinb, Jin Yongdongb, Xu Diandoua   

  1. a Division of Nuclear Technology and Applications, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049;
    b College of Chemistry, Sichuan University, Chengdu 610064;
    c Beijing Entry-Exit Inspection and Quarantine Bureau Technology Centre, Beijing 100026
  • Received:2018-09-25 Published:2018-12-05
  • Contact: 10.6023/A18090401 E-mail:malingling@ihep.ac.cn;xudd@ihep.ac.cn
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Nos. U1832212, 11405184, 11575210, 91643206) and the Key Deployment Projects of Chinese Academy of Sciences (No. ZDRW-CN-2018-1).

使用离子色谱分析了常温、常压、湿润和氧气存在条件下,NH3和Cl2γ-Al2O3颗粒物表面非均相反应的产物及其受NH3浓度、反应时间等的影响;并定量分析了NH3、Cl2、SO2和NO2单独及共存条件下,γ-Al2O3表面Cl-、NO3-和SO42-等二次无机颗粒物的生成总量.结果表明:NH3和Cl2γ-Al2O3表面具有协同作用,2 h后Cl-的生成总量可达589.65 μg,其生成量随时间延长而不断增加.表面氯化物的生成量在NH3浓度为400 ppm时达到峰值,且随NH3浓度的增加呈先增加而后减少的趋势.活性氯存在下,NH3对颗粒物表面Cl-、NO3-和SO42-的生成有促进作用,且四种气体共存时复合正反馈效应最明显.同时,本研究对NH3和Cl2在颗粒物表面的非均相反应机理及活性氯和氨的排放对大气中二次无机颗粒物的贡献进行了探讨.

关键词: 非均相反应, 二次无机颗粒物, NH3, Cl2

The effect of NH3 concentration, reaction time and other conditions on the heterogeneous reaction of NH3 and Cl2 on the surface of γ-Al2O3 particles was investigated at the room temperature, pressure and in the presence of oxygen by ion chromatography (IC). The formation of the surface species (Cl-, NO3-, and SO42-) via both individual reaction and co-existing reaction of NH3, Cl2, SO2 and NO2 on the surface of γ-Al2O3 was investigated as well. The results revealed that NH3 (400 ppm) and Cl2 (400 ppm) had synergistic effect on the surface γ-Al2O3, and the total yield of Cl- was 589.65 μg after reaction of 2 h. The formation of the surface chlorides increased firstly and then decreased with the increase of ammonia concentration, and the maximum yield of Cl- was reached at 400 ppm of NH3. In the presence of active chlorine, NH3 significantly promoted the generation of the adsorptive species on the surface, such as Cl-, NO3- and SO42-, and the most obvious synergistic effect was induced to form on the conditions of four gases co-existence. The heterogeneous reaction mechanism of NH3 with Cl2 and the influence on the atmospheric environment were also discussed as well. Additionally, the mixing ratios used in the study are extremely high compared with ambient levels, which could be as a simulation to explore whether the synergistic effect obtained in this paper are also present in the real ambient conditions. We have studied a relatively low mixing ratios for heterogeneous reaction experiments, but the content of nitrate and chloride on the surface of γ-Al2O3 were lower than the limit of detection of ion chromatography. Therefore, other researches such as Knudsen cell and smog chamber study, field monitoring, and mode study are also worth for exploring in future study. The results of this study could provide reference data for the study of the contribution of active chlorine and ammonia to the formation of secondary inorganic particles.

Key words: heterogeneous reaction, secondary inorganic particles, NH3, Cl2