Aqueous ozonolysis products of methyl- and dimethylnaphthalenes

Gaul, Michael D.; Junk, Gregor A.; Svec, Harry J.

doi:10.1021/es00162a008

Cited by 8 publications

(5 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Products found or identified from UV radiation alone and UV/H 2 O 2 oxidation of PAHs and their corresponding mass spectrum are listed in Tables 1 and 2, respectively. Results from low reaction times (approximately 90% disappearance of PAH) present the following features: (a) most of the identified products like 9-fluoren-9-one (case of fluorene), 9,10-phenanthrenedione (case of phenanthrene), or 4-ethoxy-3-methoxyphenol (case of acenaphthene) appear from both processes: UV radiation alone and UV/H 2 O 2 oxidation; (b) other products identified such as some dibenzofuran, 9-fluoren-9-one, and 9,10phenanthrenedione have also been found by different authors (Helleur et al, 1979;Bailey, 1982;Legube et al, 1986;Gaul et al, 1987;Tuhkanen, 1994) during the ozonation or UV/H 2 O 2 oxidation of fluorene, naphthalene, and other PAHs; (c) some of the compounds identified at low reaction times, like dibenzofuran or 2-methyl-1,1′-biphenyl, are potentially hazardous but they disappear at higher reaction times; (d) although only oxalic acid was identified, other carboxylic acids not identified were also found as observed in the chromatograms of derivatized samples (see Table 2 for mass spectrum data). This was especially important during the UV/H 2 O 2 oxidation of fluorene.…”

Section: Resultsmentioning

confidence: 87%

Oxidation of Polynuclear Aromatic Hydrocarbons in Water. 3. UV Radiation Combined with Hydrogen Peroxide

Beltrán

Ovejero

Rivas

1996

Ind. Eng. Chem. Res.

View full text Add to dashboard Cite

Oxidation in water of three polynuclear aromatic hydrocarbons (PAHs), fluorene, phenanthrene, and acenaphthene, with UV radiation combined with hydrogen peroxide has been studied. The effect of hydrogen peroxide concentration, pH, and bicarbonate ion has been investigated. Disappearance rates of PAHs are substantially increased with respect to those from UV radiation alone if proper conditions of hydrogen peroxide concentration and pH are established. Direct photolysis contribution decreases with the increasing hydrogen peroxide concentration and is the main way of degradation at acid pH (76% at pH 2 with 10 -3 M hydrogen peroxide concentration, for fluorene oxidation). Rate constants of reactions between the hydroxyl radical and PAHs were found to be 9.9 × 10 9 , 8.8 × 10 9 , and 13.4 × 10 9 M -1 s -1 , for fluorene, acenaphthene, and phenanthrene, respectively. Both UV radiation and UV/H 2 O 2 oxidation of PAHs yield numerous intermediate compounds. Most of these compounds disappear as oxidation time is increased.

show abstract

Section: Resultsmentioning

confidence: 87%

Oxidation of Polynuclear Aromatic Hydrocarbons in Water. 3. UV Radiation Combined with Hydrogen Peroxide

Beltrán

Ovejero

Rivas

1996

Ind. Eng. Chem. Res.

View full text Add to dashboard Cite

show abstract

“…Photochemical formation of phthalic acid from naphthalene and substituted naphthalenes has also been observed on silica surfaces () and in water in the presence of hydrogen peroxide (). Phthalic acid, phthalic anhydride, and 1,2-benzenedicarboxyaldehyde have been observed as products of the reaction of ozone with naphthalene or alkylnaphthalenes in solution ( − ). The observation of phthalic acid and related compounds from benz[ a ]anthracene photodegradation in the presence of organic aerosol constituents suggests that other mechanisms besides ozone attack can also lead to the production of phthalic acid and related compounds from benz[ a ]anthracene and possibly from other PAHs.…”

Section: Discussionmentioning

confidence: 99%

Products of Benz[a]anthracene Photodegradation in the Presence of Known Organic Constituents of Atmospheric Aerosols

Jang

McDow

1997

Environ. Sci. Technol.

115

View full text Add to dashboard Cite

Little is known about atmospheric reaction mechanisms or products of polycyclic aromatic hydrocarbons associated with aerosol particles. Products of benz[a]anthracene photodegradation were determined after irradiation of benz[a]anthracene in the presence of three common constituents of atmospheric aerosols previously found to accelerate benz[a]anthracene photodegradation; 9,10-anthraquinone, 9-xanthone, and vanillin. Irradiation was carried out in toluene, benzene, and benzene-d 6, and products were analyzed by GCMS, FTIR, and NMR. Among the major tentatively identified products were benz[a]anthracene-7,12-dione, phthalic acid, phthalic anhydride, and 1,2-benzenedicarboxaldehyde. Evidence for production of polycylic dicarboxylic acids and dialdehydes was also obtained. Product distribution was strongly influenced by solvent effects and dissolved aerosol constituents. The results suggest that products of PAH photodegradation in atmospheric aerosols are likely to be quite complex and strongly influenced by the organic composition of PAH-containing aerosol particles.

show abstract

“…5, 19951601 that intermediate steps of the ozonation of phenanthrene take place at a very rapid rate so that the ozonation is controlled by the initial step, that is, the ozone-phenanthrene reaction. It should be noted, however, that depending on the ozone concentration applied and the nature of the initial PAH other compounds like polyhydroxylated aromatics, unsaturated oxygenated aliphatics, and aromatic aldehydes can also be formed in significant amounts (Decoret et al, 1984;Legube et al, 1986a;Gaul et al, 1987). As a consequence, it is foreseen to continue this work with studies on the identification and kinetics of intermediate compounds.…”

Section: Ozonationmentioning

confidence: 99%