摘要
Unsaturated alcohols are important components in complex mixtures of oxygenated volatile organic compounds,and play a significant role in atmospheric chemistry.The uptake kinetics of 3-buten-1-ol (BO31),4-penten-1-ol (PO41) and 3-methyl3-buten-1-ol (MBO331) into 20 wt%-80 wt% H2SO4 solutions were studied,using a rotated wetted-wall reactor coupled to a differentially pumped single-photon ionization time of flight mass spectrometer (SPI-TOFMS).With increasing acidity,the uptake processes changed from reversible to irreversible (reactive).Reactive uptake was observed in 60 wt%-80 wt%,50 wt%-80 wt% and 30 wt%-80 wt% H2SO4 solutions for BO31,PO41 and MBO331,respectively.Reactive uptake coefficients were acquired and are reported here for the first time.Reactivity order followed the trend:BO31<PO41<MBO331.An electrophilic addition mechanism of H2SO4 to the C==C double bond was used to explain this trend.Atmospheric implications were discussed,based on the reactive uptake coefficients.This heterogeneous reaction with sulfuric acid aerosols may be a potential degradation pathway of unsaturated alcohols,and should not be neglected.
Unsaturated alcohols are important components in complex mixtures of oxygenated volatile organic compounds, and play a significant role in atmospheric chemistry. The uptake kinetics of 3-buten-1-ol （BO31）, 4-penten-1-ol （PO41） and 3-methyl- 3-buten-1-ol （MBO331） into 20 wt%-80 wt% H2SO4 solutions were studied, using a rotated wetted-wall reactor coupled to a differentially pumped single-photon ionization time of flight mass spectrometer （SPI-TOFMS）. With increasing acidity, the uptake processes changed from reversible to irreversible （reactive）. Reactive uptake was observed in 60 wt%-80 wt%, 50 wt%-80 wt% and 30 wt%-80 wt% H2SO4 solutions for BO31, PO41 and MBO331, respectively. Reactive uptake coefficients were acquired and are reported here for the first time. Reactivity order followed the trend： BO31〈PO41〈MBO331. An electrophilic addition mechanism of H2SO4 to the C=C double bond was used to explain this trend. Atmospheric implications were discussed, based on the reactive uptake coefficients. This heterogeneous reaction with sulfuric acid aerosols may be a potential degradation pathway of unsaturated alcohols, and should not be neglected.
基金
supported by the Knowledge Innovation Program of Chinese Academy of Sciences (KJCX2-YW-N24,KZCX2-YW-205)
the National Natural Science Foundation of China (40925016,40830101)
