The ozonation of pyrene: Pathway and product identification

Atmospheric Environment

Yang

Meng

et al. 2010

a b s t r a c tThe reactions of gas-phase phenanthrene and suspended phenanthrene particles with ozone were conducted in a 200l chamber. The secondary organic aerosol formation was observed in the reaction of gas-phase phenanthrene with ozone and simultaneously the size distribution of the secondary organic aerosol was monitored with a scanning mobility particle sizer during the formation process. The particulate ozonation products from both reactions were analyzed with a vacuum ultraviolet photoionization aerosol time-of-flight mass spectrometer. 2,2 0 -Diformylbiphenyl was identified as the dominant product in both homogeneous and heterogeneous reactions of phenanthrene with ozone. GC/MS analysis of ozonation products of phenanthrene in glacial acetic acid was carried out for assigning time-of-flight mass spectra of reaction products formed in the homogeneous and heterogeneous reactions of phenanthrene with ozone.

Section: Resultsmentioning

confidence: 99%

Homogeneous and heterogeneous reactions of phenanthrene with ozone

Atmospheric Environment

Yang

Meng

et al. 2010

“…The degradation pathways are such that the oxidation reaction involving hydroxyl radicals or O 3 react with aromatic compounds such as PAHs at near diffusion-controlled rates by abstracting hydrogen atoms or by addition to double bonds (Haag & Yao, 1992). Ozone may attack double bonds directly or it can form reactive hydroxyl radicals (which attack double bonds) by decomposing water (Legrini, Oliveros, & Braun, 1993;Gurol & Singer, 1982;Yao, Huang, & Masten, 1998a, 1998b. The reaction proceeds with complex pathways producing numerous intermediates.…”

Section: Chemical Degradationmentioning

confidence: 99%

Polycyclic Aromatic Hydrocarbons Degradation Techniques: A Review

Ukiwe¹,

Egereonu²,

Njoku³

et al. 2013

IJC

The demand for processed petroleum products and agricultural produce has exposed our environment to polycyclic aromatic hydrocarbons (PAHs) contamination. PAHs stick to solid sediments and are ubiquitous including soil, water and air. Their presence in these media creates problems because consuming products obtained from these sources could be deleterious to human health since several of these compounds (benz(a)anthracene, benzo(a)pyrene, chrysene etc) have been implicated in causing tumors in animals and cancer in humans. The present review describes several remediation techniques which are efficient and cost effective in removing PAHs from the environment. Some of these conventional clean-up methods are not only environmental friendly; they also present a novel approach in reducing the ability of PAHs to cause prospective risk to humans and the ecosystem.

“…The attack on C atom usually leads to substitution of H atoms followed by formation of phenol-or quinoid-type products, whereas the attack on C= =C double bond results in the ring cleavage followed by formyl-and carboxy-type products formation (Bailey, 1982;Perraudin et al, 2007;Wang et al, 2007;Yao et al, 1998aYao et al, , 1998b. It has been reported that position 9(10)-of An is more susceptible to be attacked to produce anthrone and thereby further forming anthraquinone (Mmereki et al, 2004;Perraudin et al, 2007).…”

Section: Reaction Pathwaymentioning

confidence: 99%

“…In the last decade, the reactions of gas phase oxidants with PAHs dissolved in organic solvents or coated on various kinds of nucleus were studied intensively. Lots of investigations on the product identifications of the gas-liquid and gas-solid reactions of atmospheric oxidants with PAHs have been carried out (Ma et al, 2011;Miet et al, 2009aMiet et al, , 2009bMiet et al, , 2009cMmereki and Donaldson, 2003;Mmereki et al, 2004;Nájera et al, 2011;Pöschl et al, 2001;Perraudin et al, 2007aPerraudin et al, , 2007bRaja and Valsaraj, 2006;Yao et al, 1998b;Zhang et al, 2010Zhang et al, , 2011.…”

Section: Introductionmentioning

confidence: 99%

Homogeneous and heterogeneous reactions of anthracene with selected atmospheric oxidants

Shu

Journal of Environmental Sciences

et al. 2013

The reactions of gas-phase anthracene and suspended anthracene particles with O 3 and O 3 -NO were conducted in a 200-L reaction chamber, respectively. The secondary organic aerosol (SOA) formations from gas-phase reactions of anthracene with O 3 and O 3 -NO were observed. Meanwhile, the size distributions and mass concentrations of SOA were monitored with a scanning mobility particle sizer (SMPS) during the formation processes. The rapid exponential growths of SOA reveal that the atmospheric lifetimes of gas-phase anthracene towards O 3 and O 3 -NO are less than 20.5 and 4.34 hr, respectively. The particulate oxidation products from homogeneous and heterogeneous reactions were analyzed with a vacuum ultraviolet photoionization aerosol time-of-flight mass spectrometer (VUV-ATOFMS). Gas chromatograph/mass spectrometer (GC/MS) analyses of oxidation products of anthracene were carried out for assigning the time-of-flight (TOF) mass spectra of products from homogeneous and heterogeneous reactions. Anthrone, anthraquinone, 9,10-dihydroxyanthracene, and 1,9,10-trihydroxyanthracene were the ozonation products of anthracene, while anthrone, anthraquinone, 9-nitroanthracene, and 1,8-dihydroxyanthraquinone were the main products of anthracene with O 3 -NO.