192-97-2Relevant articles and documents
Novel Annelation Reaction: Synthesis of Polycyclic Hydrocarbons from o-Quinones
Sukumaran, Kutikat B.,Harvey, Ronald G.
, p. 2740 - 2745 (1981)
A novel general synthesis of polycyclic aromatic ring systems involving initial reaction of polycyclic o-quinone with lithium acetylide, reduction of the resulting diacetylenic diol with LiAlH4 to the corresponding divinyl diol, and finally cyclization and dehydration with HI or POCl3 to a polyarene having one more aromatic ring is reported.Syntheses of triphenylene, dibenzanthracene, benzopyrene, and benzochrysene by this means from phenanthrene-9,10-dione, benzanthracene-5,6-dione, pyrene-4,5-dione, and chrysene-5,6-dione, respectively, are described.Yields are high (94-97percent) in the initial two steps and good (52-74percent) in the final stage.The divinyl diol intermediates may be generated directly, though in lower yield, via direct reaction of the quinones with vinylmagnesium bromide or vinyllithium reagents.Various related reactions are also explored, and evidence concerning the stereochemistries of the intermediates and the mechanisms of these reactions is discussed.
Spectrometry and reactivity of benzanthrenyl and 1-hydroperylenyl anions
Van Dijk, Joost T. M.,Van De Panne, Berit J.,Bleeker, Annemarie C.,Lugtenburg, Johan,Cornelisse, Jan
, p. 2647 - 2662 (1996)
Charge distribution and reactivity of benzanthrenyl (1-) and 1-methyl-1-hydroperylenyl anion (2-) are examined by means of semiempirical calculations, NMR spectroscopy and reactions with electrophiles. Highest charge density and reactivity are located at position 7 of 1- and the comparable position 12b of 2-. A small degree of reactivity is located at positions 4 and 6 of 1-, as shown by reactions. Generally, a good correlation between calculated charge distribution and charge distribution obtained from 13C NMR is observed.
Emission factors for carbonaceous particles and polycyclic aromatic hydrocarbons from residential coal combustion in China
Chen, Yingjun,Sheng, Guoying,Bi, Xinhui,Feng, Yanli,Mai, Bixian,Fu, Jiamo
, p. 1861 - 1867 (2008/12/21)
Emission factors of carbonaceous particles, including black carbon (BC) and organic carbon (OC), and polycyclic aromatic hydrocarbons (PAHs) were determined for five coals, which ranged in maturity from sub-bituminous to anthracite. They were burned in the form of honeycomb briquettes in a residential coalstove, one of the most common fuel/stove combinations in China. Smoke samples were taken through dilution sampling equipment, with a high volume sampler that could simultaneously collect emissions in both particulate and gaseous phases, and a cascade impactor that could segregate particles into six fractions. Particulate BC and OC were analyzed by a thermal-optical method, and PAHs in emissions of both phases were analyzed by GC-MS. Burning of bituminous coals produced the highest emission factors of particulate matter (12.91 g/kg), BC (0.28 g/kg), OC (7.82 g/kg), and 20 PAHs (210.6 mg/kg) on the basis of burned dry ash-free (daf) coal, while the anthracite honeycomb-briquette was the cleanest household coal fuel. The size-segregated results show that more than 94% of the particles were submicron, and calculated mass median aerodynamic diameters (MMAD) of all particles were under 0.3 μm. Based on the coal consumption in the residential sector of China, 290.24 Gg (gigagrams) of particulate matter, 5.36 Gg of BC, 170.33 Gg of OC, and 4.72 Gg of 20 PAHs mass were emitted annually from household honeycomb-briquette burning during 2000. Anthracite coal should be selected preferentially and more advanced burning conditions should be applied in domestic combustion, from the viewpoint of both climate change and adverse health effects.
Semivolatile and volatile compounds in combustion of polyethylene
Font, Rafael,Aracil, Ignacio,Fullana, Andrés,Conesa, Juan A.
, p. 615 - 627 (2007/10/03)
The evolution of semivolatile and volatile compounds in the combustion of polyethylene (PE) was studied at different operating conditions in a horizontal quartz reactor. Four combustion runs at 500 and 850°C with two different sample mass/air flow ratios and two pyrolytic runs at the same temperatures were carried out. Thermal behavior of different compounds was analyzed and the data obtained were compared with those of literature. It was observed that α,ω-olefins, α-olefins and n-paraffins were formed from the pyrolytic decomposition at low temperatures. On the other hand, oxygenated compounds such as aldehydes were also formed in the presence of oxygen. High yields were obtained of carbon oxides and light hydrocarbons, too. At high temperatures, the formation of polycyclic aromatic hydrocarbons (PAHs) took place. These compounds are harmful and their presence in the combustion processes is related with the evolution of pyrolytic puffs inside the combustion chamber with a poor mixture of semivolatile compounds evolved with oxygen. Altogether, the yields of more than 200 compounds were determined. The collection of the semivolatile compounds was carried out with XAD-2 adsorbent and were analyzed by GC-MS, whereas volatile compounds and gases were collected in a Tedlar bag and analyzed by GC with thermal conductivity and flame ionization detectors.
Transient puffs of trace organic emissions from a batch-fed waste propellant incinerator
Hart, John R.
, p. 559 - 569 (2007/10/03)
Emissions data have been obtained from a waste propellant incinerator. The incinerator is a dual fixed hearth, controlled air incinerator equipped with acid gas and particulate scrubbing. Puffing has been evident in this waste propellant incinerator by spikes in the CO concentration. Transient puffs of organics may travel down the combustion chambers and lead to stack emissions. The major conclusions from this study are that (1) transient puffs are formed due to the semi-batch feed nature of the combustion process (causing a local oxygen deficiency) and high water content of the desensitized propellant; (2) in batch-fed combustors, puffs can contribute to most of the organic emissions (which are relatively low) measured with US EPA sampling and analytical methods; (3) it is estimated that batch-fed combustion contributes up to 7-18 times more emissions than steady-state combustion will generate; (4) by applying dispersion analyses to determine the amount of oxygen deficiency in the flame zone, the combustion zone concentration of CO during batch-fed operation could be as high as 160,000 ppm, compared to a measured peak stack concentration of 1200 ppm CO; and (5) an organic sample is collected and averaged over at least a 2-h period that smooths out the transient peaks of organics emissions during batch-fed operation. For emissions that are associated with long-term potential health impacts, this is an appropriate sampling method. However, if a compound has a short-term potential health impact, it may be important to measure the time-resolved emissions of the compound.
