Heterogeneous reaction of NO_(2) with mineral dust aerosol may play important roles in troposphere chemistry,and has been investigated by a number of laboratory studies.However,the influence of mineralogy on this reac...Heterogeneous reaction of NO_(2) with mineral dust aerosol may play important roles in troposphere chemistry,and has been investigated by a number of laboratory studies.However,the influence of mineralogy on this reaction has not been well understood,and its impact on aerosol hygroscopicity is not yet clear.This work investigated heterogeneous reactions of NO_(2)(∼10 ppmv)with K-feldspar,illite,kaolinite,montmorillonite and Arizona Test Dust(ATD)at room temperature as a function of relative humidity(<1%to 80%)and reaction time(up to 24 hr).Heterogeneous reactivity towards NO_(2) was low for illite,kaolinite,montmorillonite and ATD,and uptake coefficients of NO_(2),γ(NO_(2)),were determined to be around or smaller than 1×10^(−8);K-feldspar exhibited higher reactivity towards NO_(2),and CaCO_(3) is most reactive among the nine mineral dust samples considered in this and previous work.After heterogeneous reaction with NO_(2) for 24 hr,increase in hygroscopicity was nearly insignificant for illite,kaolinite and montmorillonite,and small but significant for K-feldspar;in addition,large increase in hygroscopicity was observed for ATD,although the increase in hygroscopicity was still smaller than CaCO_(3).展开更多
基金supported by the National Natural Science Foundation of China(No.42022050)Guangdong Foundation for Program of Science and Technology Research(Nos.2019B121205006 and 2020B1212060053)+1 种基金the Guangdong Science and Technology Department(No.2017GC010501)CAS Pioneer Hundred Talents program.
文摘Heterogeneous reaction of NO_(2) with mineral dust aerosol may play important roles in troposphere chemistry,and has been investigated by a number of laboratory studies.However,the influence of mineralogy on this reaction has not been well understood,and its impact on aerosol hygroscopicity is not yet clear.This work investigated heterogeneous reactions of NO_(2)(∼10 ppmv)with K-feldspar,illite,kaolinite,montmorillonite and Arizona Test Dust(ATD)at room temperature as a function of relative humidity(<1%to 80%)and reaction time(up to 24 hr).Heterogeneous reactivity towards NO_(2) was low for illite,kaolinite,montmorillonite and ATD,and uptake coefficients of NO_(2),γ(NO_(2)),were determined to be around or smaller than 1×10^(−8);K-feldspar exhibited higher reactivity towards NO_(2),and CaCO_(3) is most reactive among the nine mineral dust samples considered in this and previous work.After heterogeneous reaction with NO_(2) for 24 hr,increase in hygroscopicity was nearly insignificant for illite,kaolinite and montmorillonite,and small but significant for K-feldspar;in addition,large increase in hygroscopicity was observed for ATD,although the increase in hygroscopicity was still smaller than CaCO_(3).
