Non-methane hydrocarbons(NMHCs)are a common type of volatile organic compounds(VOCs)pollutant in the petrochemical industry and have attracted widespread attention because of their adverse health effects and environme...Non-methane hydrocarbons(NMHCs)are a common type of volatile organic compounds(VOCs)pollutant in the petrochemical industry and have attracted widespread attention because of their adverse health effects and environmental impacts.In this paper,we report a new porous slurry formed with zeolitic imidazolate framework-8(ZIF-8)and iso-hexadecane to capture the low-concentration and multi-component NMHCs(mainly ethane(C_(2)H_(6)),propane(C_(3)H_(8)),and n-butane(n-C_(4)H_(10)))from the oil field exhaust.The sorption capacity of C_(2)H_(6)in the slurry is significantly higher than that of nitrogen(N_(2))and methane(CH_(4)).Moreover,the slurry demonstrated a clear advantage for C_(2)H_(6)over N_(2)and CH_(4)in competitive adsorption through the pressure-drop curves.In the NMHCs capture experiments,the C_(3)H_(8)and n-C_(4)H_(10)concentrations after purification can be reduced to below 100 ppm,while the C_(2)H_(6)concentration can reach approximately 180 ppm.More encouragingly,in the breakthrough tests,the slurry exhibits a perfect kinetic separation selectivity for multi-component NMHCs.Furthermore,to avoid structural collapse of ZIF-8 material during long-term use in acidic and wet environments,a certain amount of 2-methylimidazole was retained in the slurry as a protective agent in the material synthesis process.In this way,the ZIF-8 materials in the slurry can retain the stable characteristic structure in an aqueous and acidic environment and keep the capture capacity for NMHCs without degradation.We believe the porous ZIF-8/iso-hexadecane slurry is a promising capture agent for low-concentration and multi-component NMHCs with strong purification capacity and stability.展开更多
In order to study the variation characteristics of concentration of the atmospheric non-methane hydrocarbons （NMHCs） in background area of China, the atmospheric concentrations of NMHCs were measured at Lin＇an （LA...In order to study the variation characteristics of concentration of the atmospheric non-methane hydrocarbons （NMHCs） in background area of China, the atmospheric concentrations of NMHCs were measured at Lin＇an （LA） regional GAW （Global Atmosphere Watch） Station （30°25＇N, 119°44＇E; 132.0 m ASL） and Shangdianzi （SDZ） regional GAW Station （40°19＇N, 117°07＇E; 286.5 m ASL） with the sorbent sorption/thermal desorption/gas chromatographic method. Totally 145 samples were collected during the period of October 2003 and July 2004. Among the 52 NMHC species of C2-C10 detected there were 26 alkanes, 17 alkenes, and 9 aromatics. The average concentrations of total NMHCs （TNMHCs） at LA and SDZ were （238.5±126.0） ×10^-9C and （278.7±185.5）×10^-9C, respectively. The results showed the ambient concentrations of TNMHCs at LA regional GAW Station increased notably over the last decade. The compositions of NMHCs at SDZ and LA were relatively similar. The proportions of alkanes, alkenes, and aromatics for SDZ and LA were in ranges of （27.3±4.0）%, （10.3±3.5）%, and （62.5±4.8）%, respectively, with features of vehicle exhaust emissions. The concentrations of NMHCs at the two sites showed obvious diurnal and seasonal variations. The TNMHC concentrations in October-November were high at the two sites, and relatively low in April and July. The diurnal variation patterns at the sites were different. The high TNMHC concentrations at SDZ normally appeared in evening and night, but appeared in morning at LA. The TNMHCs concentrations at the two sites were significantly influenced by the meteorological condition. The high TNMHC concentration associated with the local wind from the urban areas or traffic in upper reaches.展开更多
基金supported by the National Natural Science Foundation of China(Nos.22278429 and 22127812)Beijing Science and Technology Program,China(No.Z181100005118010)+1 种基金Science Foundation of China University of Petroleum,Beijing(No.2462021QNXZ011)State Key Laboratory of Heavy Oil Processing,China University of Petroleum
文摘Non-methane hydrocarbons(NMHCs)are a common type of volatile organic compounds(VOCs)pollutant in the petrochemical industry and have attracted widespread attention because of their adverse health effects and environmental impacts.In this paper,we report a new porous slurry formed with zeolitic imidazolate framework-8(ZIF-8)and iso-hexadecane to capture the low-concentration and multi-component NMHCs(mainly ethane(C_(2)H_(6)),propane(C_(3)H_(8)),and n-butane(n-C_(4)H_(10)))from the oil field exhaust.The sorption capacity of C_(2)H_(6)in the slurry is significantly higher than that of nitrogen(N_(2))and methane(CH_(4)).Moreover,the slurry demonstrated a clear advantage for C_(2)H_(6)over N_(2)and CH_(4)in competitive adsorption through the pressure-drop curves.In the NMHCs capture experiments,the C_(3)H_(8)and n-C_(4)H_(10)concentrations after purification can be reduced to below 100 ppm,while the C_(2)H_(6)concentration can reach approximately 180 ppm.More encouragingly,in the breakthrough tests,the slurry exhibits a perfect kinetic separation selectivity for multi-component NMHCs.Furthermore,to avoid structural collapse of ZIF-8 material during long-term use in acidic and wet environments,a certain amount of 2-methylimidazole was retained in the slurry as a protective agent in the material synthesis process.In this way,the ZIF-8 materials in the slurry can retain the stable characteristic structure in an aqueous and acidic environment and keep the capture capacity for NMHCs without degradation.We believe the porous ZIF-8/iso-hexadecane slurry is a promising capture agent for low-concentration and multi-component NMHCs with strong purification capacity and stability.
基金Ministry of Science and Technology(Project No.2001DIA10009).
文摘In order to study the variation characteristics of concentration of the atmospheric non-methane hydrocarbons （NMHCs） in background area of China, the atmospheric concentrations of NMHCs were measured at Lin＇an （LA） regional GAW （Global Atmosphere Watch） Station （30°25＇N, 119°44＇E; 132.0 m ASL） and Shangdianzi （SDZ） regional GAW Station （40°19＇N, 117°07＇E; 286.5 m ASL） with the sorbent sorption/thermal desorption/gas chromatographic method. Totally 145 samples were collected during the period of October 2003 and July 2004. Among the 52 NMHC species of C2-C10 detected there were 26 alkanes, 17 alkenes, and 9 aromatics. The average concentrations of total NMHCs （TNMHCs） at LA and SDZ were （238.5±126.0） ×10^-9C and （278.7±185.5）×10^-9C, respectively. The results showed the ambient concentrations of TNMHCs at LA regional GAW Station increased notably over the last decade. The compositions of NMHCs at SDZ and LA were relatively similar. The proportions of alkanes, alkenes, and aromatics for SDZ and LA were in ranges of （27.3±4.0）%, （10.3±3.5）%, and （62.5±4.8）%, respectively, with features of vehicle exhaust emissions. The concentrations of NMHCs at the two sites showed obvious diurnal and seasonal variations. The TNMHC concentrations in October-November were high at the two sites, and relatively low in April and July. The diurnal variation patterns at the sites were different. The high TNMHC concentrations at SDZ normally appeared in evening and night, but appeared in morning at LA. The TNMHCs concentrations at the two sites were significantly influenced by the meteorological condition. The high TNMHC concentration associated with the local wind from the urban areas or traffic in upper reaches.
