From coal to single-stage and two-stage products: A reactive model of coal structure

Shinn, John H.

doi:10.1016/0016-2361(84)90422-8

Cited by 390 publications

(201 citation statements)

References 23 publications

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“…In this range, a shift toward a fly ash pattern is also found. The initial decrease in the (20), and confirmed by Bruinsma (21) in the emission of benzofurans and dibenzofurans during coal combustion.…”

Section: Resultssupporting

confidence: 60%

Mechanism of formation of polychlorinated dibenzo-p-dioxins and dibenzofurans in the catalyzed combustion of carbon

Luijk¹,

Akkerman²,

Slot³

et al. 1994

Environ. Sci. Technol.

196

124

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Mechanism of formation of polychlorinated dibenzo-p-dioxins and dibenzfurans in the catalyzed combustion of carbon. Luijk, R.; Akkerman, D.M.; Slot, P.C.; Olie, K.; Kapteijn, F. Published in:Environmental Science and Technology DOI:10.1021/es00051a019Link to publication Citation for published version (APA):Luijk, R., Akkerman, D. M., Slot, P. C., Olie, K., & Kapteijn, F. (1994). Mechanism of formation of polychlorinated dibenzo-p-dioxins and dibenzfurans in the catalyzed combustion of carbon. Environmental Science and Technology, 28, 312-321. DOI: 10.1021/es00051a019 General rightsIt is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), other than for strictly personal, individual use, unless the work is under an open content license (like Creative Commons). Disclaimer/Complaints regulationsIf you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the Library know, stating your reasons. In case of a legitimate complaint, the Library will make the material inaccessible and/or remove it from the website. Please Ask the Library: http://uba.uva.nl/en/contact, or a letter to: Library of the University of Amsterdam, Secretariat, Singel 425, 1012 WP Amsterdam, The Netherlands. You will be contacted as soon as possible. Combustion experiments of an activated carbon (Norit RX Extra), catalyzed by CuC12, were conducted in triplicate in a flow of moist air containing 5 vol % HC1 at 300 "C to reveal the mechanism of formation of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). The catalyst concentration was varied from 0, 0.1,0.5,1.0, to 5.0 wt %. After partial combustion (1 h), the samples were analyzed on the presence of PCDDs and PCDFs. The total yield of these compounds amounted to 19 (0.1 wt % CuC12) and 2 (5.0 wt % CuClz) pg/g of carbon. The PCDD/PCDF ratio showed a decrease from 33 to 0.2. At low copper concentrations, predominantly PCDDs are formed with an isomer pattern that can be explained completely as a product of chlorophenol condensation reactions. At high copper concentrations, the PCDD/PCDF isomer distribution pattern shifts toward a characteristic waste incineration fly ash pattern. A proposal for the mechanism of formation of PCDDs and PCDFs in the catalyzed combustion of carbon will be presented. Condensation reactions of 2,4,6-trichlorophenol on carbon ( O w t 9% CuC12)

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Section: Resultssupporting

confidence: 60%

Mechanism of formation of polychlorinated dibenzo-p-dioxins and dibenzofurans in the catalyzed combustion of carbon

Luijk¹,

Akkerman²,

Slot³

et al. 1994

Environ. Sci. Technol.

196

124

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“…The two-phase model proposed by Marzec et al stated that there are a large number of polycyclic aromatic hydrocarbons in coal molecules which are linked by aliphatic chains or ether bonds, forming the macromolecular phase of the coal molecules; the second phase is composed of smaller aromatic molecules which are distributed between the gaps of the first phase (Marzec 1986). This is extremely similar to the coal structure model raised by Shinn in 1986 through the products from the first and second stage liquefaction of coal (Shinn 1984). This type of structure explains the phenomena of organic solvents extracting small molecules from coal and the phenomena of coal swelling in certain organic solvents, thus it is the most authoritative theory for coal structure.…”

Section: Structures Of Depolymerized Coal Samples Obtained Under Diffsupporting

confidence: 79%

Effect of pH conditions on the depolymerization of Wucaiwan coal by mixed acids/ultrasound method and the product structures and performance

Zhang

Maimaiti

Zhang

et al. 2017

Int J Coal Sci Technol

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The cleavage of the aliphatic chain or ether bond connecting the polycyclic aromatic hydrocarbons in coal can be achieved by not only hydrogenation reduction but also oxidative acid treatment. In this paper, coal samples from Wucaiwan in Xinjiang were pretreated with HNO 3 followed by mixed acids/ultrasound treatment. The depolymerized coal samples obtained under different pH conditions were then separated by fractional washing. The structures and properties of the resulting coal samples were studied by elemental analysis, FT-IR, XRD, TG-DTA, TEM, UV-Vis, and PL. The results showed that when pH = 0.012, the obtained coal samples were fragments stripped off from the raw coal samples by ultrasound in strong acid conditions, aliphatic hydrocarbons linked with oxygen-containing groups such as nitro group, a small amount of small aromatic molecules and mineral salts; when pH = 1.99-4.09, the obtained coal samples were polycyclic aromatic hydrocarbons linked with oxygen-containing groups such as nitro group,possessing the annulus wall of multilayer graphene fragment structures built up by sp 2 carbons, and they are typical fluorescent substances of carbon nanoparticle structure. The former has no solubility in organic solvents, while the latter can be well dissolved in polar solvents such as acetone. All the depolymerized coal samples obtained under different pH conditions exhibited good absorption and ability of fluorescence emission.

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“…This rationale is very similar to that of petroleum system modeling, and in the same way the weighting and detail of input and output data will depend on the use for which these models are constructed. The first molecular models of sedimentary organic matter were built by coal scientists as early as 1942 by Fuchs and Sandhoff; then many other coal models based on an increasing number of analytical results from different techniques were built (Given, 1960;Spiro, 1981;Spiro and Kosky, 1982;Shinn, 1984;Solomon, 1981). Models for other types of sedimentary organic matter were constructed first for oil shales such as the Green River shale (Burlingame et al, 1968;Yen., 1976;Siskin et al, 1995), then for the three main types of kerogen at various maturity stages Vandenbroucke, 1986, 1987).…”

Section: Why Conceptual Models?mentioning

confidence: 99%

Kerogen: from Types to Models of Chemical Structure

Vandenbroucke

2003

Oil & Gas Science and Technology - Rev. IFP

153

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Résumé -Les kérogènes : de la notion de types aux modèles de structure chimique -Le but de cet article est de présenter, à travers une revue des développements conceptuels et analytiques en géochimie dans la période , les principales étapes qui ont conduit, à travers la préparation et l'analyse des kérogènes d'une part, et l'étude de systèmes pétroliers de référence d'autre part, aux notions de types, chemins d'évolution et modèles statistiques de structure chimique des kérogènes. Le kérogène est défini comme la matière organique des sédiments qui produit le pétrole, opposant ainsi le pétrole, soluble dans les solvants organiques courants, à son complément insoluble. Ce kérogène étant une matière organique complexe intimement mélangée aux minéraux des sédiments, la première tâche a été de mettre au point un protocole fiable pour son isolement, permettant ensuite son étude par des méthodes physicochimiques variées. En parallèle, le développement des permis d'exploration pétrolière, donnant accès aux échantillons de forage, permettait la comparaison géochimique de divers systèmes pétroliers. Les comparaisons furent faites non seulement entre les compositions chimiques des huiles, roches mères et kérogènes, mais aussi sur l'époque de production du pétrole. La notion de cinétique de craquage du kérogène en pétrole résultant de ces études de systèmes pétroliers, associée à l'observation d'une compensation des facteurs temps et température, conduisit à utiliser la pyrolyse en laboratoire pour évaluer le potentiel pétrolier restant à produire par le kérogène, et donc, à la construction de l'appareil Rock-Eval. Au milieu des années 1970, les principaux paramètres géochimiques des kérogènes de certaines séries pétrolières de référence étaient disponibles pour la définition des notions de type et de chemin d'évolution des kérogènes au cours de l'enfouissement géologique des sédiments. Un pas important dans la connaissance de la composition chimique du kérogène fut franchi dans les années 1980 avec l'utilisation de nouvelles techniques de pyrolyse analytique et préparative, et leur couplage avec différents détecteurs. Les produits de pyrolyse, considérés comme briques élémentaires issues du craquage thermique du kérogène, pouvaient ainsi être analysés et quantifiés au niveau moléculaire, sans les problèmes de représentativité rencontrés avec l'analyse des extraits naturels et dus aux pertes de composés volatils et de produits ayant migré hors des roches mères. Le développement parallèle de la résonance magnétique nucléaire du 13 C en phase solide permit l'analyse et la quantification des diverses formes du carbone et de son environnement chimique dans le kérogène, ce qui n'était pas possible auparavant sous forme quantitative par la spectroscopie infrarouge ou ultraviolette. L'analyse quantitative des briques moléculaires et des groupes fonctionnels qui les assemblaient dans le kérogène permit ainsi d'élaborer des modèles moléculaires statistiques de kérogènes dans le but de visualiser l'ensemble de leur composition atomiq...

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From coal to single-stage and two-stage products: A reactive model of coal structure

Cited by 390 publications

References 23 publications

Mechanism of formation of polychlorinated dibenzo-p-dioxins and dibenzofurans in the catalyzed combustion of carbon

Mechanism of formation of polychlorinated dibenzo-p-dioxins and dibenzofurans in the catalyzed combustion of carbon

Effect of pH conditions on the depolymerization of Wucaiwan coal by mixed acids/ultrasound method and the product structures and performance

Kerogen: from Types to Models of Chemical Structure

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