Efficient photochemical generation of peroxycarboxylic nitric anhydrides with ultraviolet light-emitting diodes

Abstract

Abstract. Photochemical sources of peroxycarboxylic nitric anhydrides (PANs) are utilized in many atmospheric measurement techniques for calibration or to deliver an internal standard. Conventionally, such sources rely on phosphor-coated low-pressure mercury (Hg) lamps to generate the UV light necessary to photo-dissociate a dialkyl ketone (usually acetone) in the presence of a calibrated amount of nitric oxide (NO) and oxygen (O2). In this manuscript, a photochemical PAN source in which the Hg lamp has been replaced by arrays of ultraviolet light-emitting diodes (UV-LEDs) is described. The output of the UV-LED source was analyzed by gas chromatography (PAN-GC) and thermal dissociation cavity ring-down spectroscopy (TD-CRDS). Using acetone, diethyl ketone (DIEK), diisopropyl ketone (DIPK), or di-n-propyl ketone (DNPK), respectively, the source produces peroxyacetic (PAN), peroxypropionic (PPN), peroxyisobutanoic (PiBN), or peroxy-n-butanoic nitric anhydride (PnBN) from NO in high yield (> 90 %). Box model simulations with a subset of the Master Chemical Mechanism (MCM) were carried out to rationalize product yields and to identify side products. The present work demonstrates that UV-LED arrays are a viable alternative to current Hg lamp setups.

Leaf Stomatal Control over Acyl Peroxynitrate Dry Deposition to Trees

“…PAN and PPN were synthesized in real-time via the photolysis of excess acetone or 3-pentanone, respectively, in the presence of O 2 and NO 2 ( and ). , …”

Measurement of Henry's law and liquid-phase loss rate constants of peroxypropionic nitric anhydride (PPN) in deionized water and in n-octanol

“…The Varian GC-ECD described by Tokarek et al (2014) was used for most of the experiments (see schedule in Tables S1-S4 in the supporting information (S.I.) section), though some measurements were also carried out using the Hewlett Packard (HP) GC described in (Rider et al, 2015;Zborowska et al, 2021). The Varian GC-ECD was equipped with a 30 m 115 long megabore column (Restek RTX-1701, film thickness 1 μm) and a 0.5 mL stainless steel sample loop (VICI Cheminert).…”

“…It is clear that EN was emitted in this work, though only in minute quantities (Figure 2) that in all likelihood did not affect the solubility of PPN. In contrast, the photochemical source used by Kames and Schurath (1995) likely co-emitted, as they put it, "rather high mixing ratios" (~3000 ppmv) of 3-pentanone and would have also co-emitted a myriad of water-soluble photochemical by-products such as hydroperoxides, aldehydes and α,β-dicarbonyls such as glyoxal (Rider et al, 2015). Furthermore, formation 280 of photochemical side products would have been accentuated in their work since they utilized a 254 nm Hg lamp whose high operating temperature heightens undesired secondary photochemistry (Rider et al, 2015).…”

Furoyl peroxynitrate (fur-PAN), a product of VOC–NOxphotochemistry from biomass burning emissions: photochemical synthesis, calibration, chemical characterization, and first atmospheric observations

“…Several selective photochemical methods have been developed that use either ketones, diketones, or acid chlorides to yield the desired acyl radical. [33][34][35] These photochemical sources rely on rapid formation of an excess of the desired RC(O)OO radical to convert a calibrated amount of an NO standard to NO 2 through reaction (R3) and subsequent reactions of hydroperoxyl radicals with NO. The desired PAN compound is then formed through (R1).…”

“…Conditions can be devised such that a stable, highly efficient ($93%) conversion of the NO standard can be achieved and used as a stable calibrant. 33,35,36 The reaction of bromine atom (Br) with aldehydes in the presence of NO x has been used as relatively efficient method for making PAN compounds because of the selectivity of abstraction reactions with aldehyde hydrogens. 21,37 This paper presents a method for the photochemical synthesis of fur-PAN using the photolysis of Br 2 in the presence of furfural and nitric oxide (NO) in air.…”