Nitrogen dioxide, photolytic

Figure 8, Photolytic generation of nitrogen dioxide and an aryl nitrite ester from a nitro compound, as formulated by Lippert and Kelm (27),...

Photolytic. Photolysis of acetone in air yields carbon monoxide and free radicals, but in isopropanol, pinacol is formed (Calvert and Pitts, 1966). Photolysis of acetone vapor with nitrogen dioxide via a mercury lamp gave peroxyacetyl nitrate as the major product with smaller quantities of methyl nitrate (Warneck and Zerbach, 1992). 

Photolytic. Products identified from the photoirradiation of 1-butene with nitrogen dioxide in air are epoxybutane, 2-butanone, propanal, ethanol, ethyl nitrate, carbon monoxide, carbon dioxide, methanol, and nitric acid (Takeuchi et ah, 1983). 

Photolytic. Photooxidation of 1,1-dichloroethylene in the presence of nitrogen dioxide and air yielded phosgene, chloroacetyl chloride, formic acid, HCl, carbon monoxide, formaldehyde, and ozone (Gay et al, 1976). At 298 K, 1,1-dichloroethylene reacts with ozone at a rate of 3.7 x 10 cmVmolecule-sec (Hull et al., 1973). 

Photolytic. Methyl vinyl ketone and methacrolein were reported as major photooxidation products for the reaction of 2-methyl-l,3-butadiene with OH radicals. Formaldehyde, nitrogen dioxide, nitric oxide, and HO2 were reported as minor products (Lloyd et al, 1983). Synthetic air containing gaseous nitrous acid and exposed to artificial sunlight (X = 300-450 nm) photo-oxidized 2-methyl-1,3-butadiene into formaldehyde, methyl nitrate, peroxyacetal nitrate, and a compound tentatively identified as methyl vinyl ketone (Cox et al, 1980). 

Photolytic. Glyoxal, methylglyoxal, and biacetyl were produced from the photooxidation of 1,2,3-trimethylbenzene by OH radicals in air at 25 °C (Tuazon et al., 1986a). The rate constant for the reaction of 1,2,3-trimethylbenzene and OH radicals at room temperature was 1.53 x 10 " cmVmolecule-sec (Hansen et al., 1975). A rate constant of 1.49 x 10 L/molecule-sec was reported for the reaction of 1,2,3-trimethylbenzene with OH radicals in the gas phase (Darnall et al., 1976). Similarly, a room temperature rate constant of 3.16 x 10 " cm /molecule-sec was reported for the vapor-phase reaction of 1,2,3-trimethylbenzene with OH radicals (Atkinson, 1985). At 25 °C, a rate constant of 2.69 x lO " cm /molecule-sec was reported for the same reaction (Ohta and Ohyama, 1985). 2,3-Butanedione was the only products identified from the OH radical-initiated reaction of 1,2,4-trimethylbenzene in the presence of nitrogen dioxide. The amount of 2,3-butanedione formed decreased with increased concentration of nitrogen dioxide (Bethel et al., 2000). 

Photolytic. Irradiation of vinyl chloride in the presence of nitrogen dioxide for 160 min produced formic acid, HCl, carbon monoxide, formaldehyde, ozone, and trace amounts of formyl chloride and nitric acid. In the presence of ozone, however, vinyl chloride photooxidized to carbon monoxide, formaldehyde, formic acid, and small amounts of HCl (Gay et al, 1976). Reported photooxidation products in the troposphere include hydrogen chloride and/or formyl chloride (U.S. EPA, 1985). In the presence of moisture, formyl chloride will decompose to carbon monoxide and HCl (Morrison and Boyd, 1971). Vinyl chloride reacts rapidly with OH radicals in the atmosphere. Based on a reaction rate of 6.6 x lO" cmVmolecule-sec, the estimated half-life for this reaction at 299 K is 1.5 d (Perry et al., 1977). Vinyl chloride reacts also with ozone and NO3 in the gas-phase. Sanhueza et al. (1976) reported a rate constant of 6.5 x 10 cmVmolecule-sec for the reaction with OH radicals in air at 295 K. Atkinson et al. (1988) reported a rate constant of 4.45 X 10cmVmolecule-sec for the reaction with NO3 radicals in air at 298 K. 

CASRN 75-18-3 molecular formula C2H0S FW 62.14 Photolytic. Sunlight irradiation of a mixture of methyl sulfide (initial concentrations 0.2-2.5 ppm) and oxides of nitrogen (86-580 ppb) in an outdoor chamber at various time intervals (2-7 h) yielded nitrogen dioxide, ozone, sulfur dioxide, nitric acid, formaldehyde, and methyl nitrate, a sulfate aerosol, and methane sulfonic acid (Grosjean, 1984a). 

Such information can be found in the work of Jaffe and Klein on the photolysis of NO2 in the presence of SO2. They measured the quantum yield of nitrogen dioxide decomposition by in situ NO2 absorptiometry. In the absence of SOj the quantum yield is 2, since each atom of oxygen formed in the primary photolytic process can react with another molecule of NO2... 

Photolytic nitrogen extrusion from tetrazoline derivatives (283) and (284) permits further syntheses of diaziridin-ones (285a) and -imines (285b) respectively (75AG(E)428). Thermal carbon dioxide extrusion from a five-membered precursor can also give a diaziridinimine (75JOC3112). 

Recently, results of careful experiments were reported by Ito et a/.101 They claimed that formic acid, formaldehyde, and methanol, which had been previously reported as photoelectrochemical reduction products of carbon dioxide, were observed also by photolysis of cell materials, such as electrolytes, including 15-crown-5 ether, and epoxy resin, which has often been used as the molding material of semiconductor electrodes in aqueous solutions. Previously reported reduction products were obtained also under nitrogen with (Table 4) and without (Table 5) a p-GaP photocathode under illumination. These precise experiments under improved conditions, where no photolytic products were observed, gave the result that the main reduction product of carbon dioxide at a p-GaP photocathode in aqueous electrolytes was formic acid. Thus, many kinds of products reported in previous papers83,97,100 were suggested to be due to photolysis of cell materials. 

Photolytic. A carbon dioxide yield of 19.7% was achieved when bromobenzene adsorbed on silica gel was irradiated with light (X >290 nm) for 17 h (Freitag et al., 1985). Irradiation of bromobenzene in air containing nitrogen oxides gave phenol, 4-nitrophenol, 2,4-dinitrophenol, 4-bromophenol, 3-bromonitrobenzene, 3-bromo-2-nitrophenol, 3-bromo-4-nitrophenol, 3-bromo-6-... 

Photolytic. Major products reported from the photooxidation of butane with nitrogen oxides under atmospheric conditions were acetaldehyde, formaldehyde, and 2-butanone. Minor products included peroxyacyl nitrates and methyl, ethyl and propyl nitrates, carbon monoxide, and carbon dioxide. Biacetyl, tert-butyl nitrate, ethanol, and acetone were reported as trace products (Altshuller, 1983 Bufalini et al, 1971). The amount of sec-butyl nitrate formed was about twice that of n-butyl nitrate. 2-Butanone was the major photooxidation product with a yield of 37% (Evmorfopoulos and Glavas, 1998). Irradiation of butane in the presence of chlorine yielded carbon monoxide, carbon dioxide, hydroperoxides, peroxyacid, and other carbonyl compounds (Hanst and Gay, 1983). Nitrous acid vapor and butane in a smog chamber were irradiated with UV light. Major oxidation products identified included 2-butanone, acetaldehyde, and butanal. Minor products included peroxyacetyl nitrate, methyl nitrate, and unidentified compounds (Cox et al., 1981). 

Photolytic. Sunlight irradiation of a methyl mercaptan-nitrogen oxide mixture in an outdoor chamber yielded formaldehyde, sulfur dioxide, nitric acid, methyl nitrate, methanesulfonic acid, and an inorganic sulfate (Grosjean, 1984a). 

Photolytic. Photolysis products include carbon monoxide, ethylene, free radicals and a polymer (Calvert and Pitts, 1966). Anticipated products from the reaction of acrylonitrile with ozone or hydroxyl radicals in the atmosphere are glyoxal, formaldehyde, formic acid and carbon dioxide (Cupitt, 1980). The major product reported from the photooxidation of acrolein with nitrogen oxides is formaldehyde with a trace of glyoxal (Altshuller, 1983). Osborne et al. (1962) reported that acrolein was stable at 30°C and UV light (2. = 313 nm) in the presence and absence of oxygen. 

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