Heterogeneous reactions of mineral dust aerosol: implications for tropospheric oxidation capacity

Abstract

Abstract. Heterogeneous reactions of mineral dust aerosol with trace gases in the atmosphere could directly and indirectly affect tropospheric oxidation capacity, in addition to aerosol composition and physicochemical properties. In this article we provide a comprehensive and critical review of laboratory studies of heterogeneous uptake of OH, NO 3 , O 3 , and their directly related species as well (including HO 2 , H 2 O 2 , HCHO, HONO, and N 2 O 5 ) by mineral dust particles. The atmospheric importance of heterogeneous uptake as sinks for these species is assessed (i) by comparing their lifetimes with respect to heterogeneous reactions with mineral dust to lifetimes with respect to other major loss processes and (ii) by discussing relevant field and modeling studies. We have also outlined major open questions and challenges in laboratory studies of heterogeneous uptake by mineral dust and discussed research strategies to address them in order to better understand the effects of heterogeneous reactions with mineral dust on tropospheric oxidation capacity.

Hygroscopic Properties of Saline Mineral Dust From Different Regions in China: Geographical Variations, Compositional Dependence, and Atmospheric Implications

“…Aerosol liquid water (or surface‐adsorbed water) largely determines kinetics, mechanisms, and products of heterogeneous reactions (Rubasinghege & Grassian, ; Tang et al, ; Wu et al, ). Mitroo et al () found that at a given RH, N 2 O 5 uptake coefficients decreased whereas ClNO 2 production yield increased with soluble ion fractions in saline mineral dust samples.…”

An in situ flow tube system for direct measurement of N<sub>2</sub>O<sub>5</sub> heterogeneous uptake coefficients in polluted environments

“…The latter treatment is suitable when ambient concentrations are low and the air mass is relatively stable, but it may be problematic in polluted environments with high fresh NO x emissions, high O 3 concentrations, and rapidly changing air mass. Several recent studies have revealed active N 2 O 5 heterogeneous processes on aerosols at polluted sites and its significant impacts on photochemistry and secondary aerosol formation due to abundant NO x , O 3 , and aerosols (e.g., Li et al, 2016;Tham et al, 2016;Wang et al, 2016;Yun et al, 2018). The γ N 2 O 5 derived from ambient concentration measurements showed different characteristics and dependence compared to previous measurements in relatively clean environments (Morgan et al, 2015;.…”

Atmospheric Processing of Loess Particles in a Polluted Urban Area of Northwestern China

“…In this study, as shown in Figure g, Oxalate/Ca + showed a three‐spike diurnal pattern peaking at 3:00, 5:00, and 17:00. The aqueous oxidation of glyoxal by OH, H 2 O 2 , and other peroxides could drive the nighttime elevation of oxalate in the dust droplets (Tang et al, ). The nighttime peak of oxalate has been observed by Sullivan and Prather (), but they proposed that the peak was majorly caused by long‐range transport.…”