Pyrolysis of Aromatics and Related Heterocyclics

Madison, J. Mark; Roberts, Richard L.

doi:10.1021/ie50578a044

Cited by 77 publications

(30 citation statements)

References 7 publications

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“…By applying first-order perturbation theory to the Huckel molecular orbitals (Heilbronner et al 1976), They estimated electron localization energies (δΕ π ). Previous workers (Lewis et al 1963, Madison et al 1963) also supported these findings. They found that molecules with "zig-zag" edges (A) are more reactive than molecules with "arm-chair" edges (B) (Figure 1).…”

Section: Selective Gasificationsupporting

confidence: 70%

Kinetics and Catalysis of Carbon Gasification

Marsh

Kuo

1989

Introduction to Carbon Science

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Section: Selective Gasificationsupporting

confidence: 70%

Kinetics and Catalysis of Carbon Gasification

Marsh

Kuo

1989

Introduction to Carbon Science

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“…Thermal cracking of model compounds confirm that volatility of the fragments is a major influence in carbon residue formation. Indeed, the formation of a coke-like substance during thermal decomposition of aromatic compounds and related heterocyclic compounds are dependent upon the structure, and hence the volatility, of the polynuclear aromatic hydrocarbon but more specifically on: -the degree of polynuclear condensation in petroleum; -the average number of alkyl groups on the polynuclear aromatic systems; -the occurrence of heteroatoms in the ring; -the type of heteroatom (Madison and Roberts, 1958;Lewis and Edstrom, 1963;Singer, 1964, 1967;Lewis, 1980Lewis, , 1982. Nitrogen species also appear to contribute to the pattern of the thermal cracking.…”

Section: Thermal Decompositionmentioning

confidence: 99%

Petroleum Asphaltenes - Part 2: the Effect of Asphaltene and Resin Constituents on Recovery and Refining Processes

Speight¹

2004

Oil & Gas Science and Technology - Rev. IFP

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Résumé -Les asphaltènes, composés pétroliers -Partie 2 : L'effet des asphaltènes et des résines sur les procédés de récupération et de raffinage -Le pétrole est un système complexe en équilibre délicat qui dépend des relations entre ces constituants, relations gouvernées par les interactions molécu-laires. Ainsi, des schémas de récupération et de raffinage, en particulier ceux traitant des dépôts asphalté-niques (produits de dégradation ou de réaction des asphaltènes et des résines) peuvent être proposés grâce aux connaissances acquises sur la nature des asphaltènes, des résines et de leurs interactions au sein d'un brut. Abstract

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“…Previous work in this laboratory (Yeboah et al, 1980) demonstrated yield reductions and quality improvement when fresh coal pyrolysis tars were treated with calcium oxide (CaO or calcined dolomite), at temperatures above 400 "C at contact times of about 1 s. Pyrolysis of Illinois No. Literature data to assess the role of CaO were unavailable, although there have been several studies of the homogeneous and heterogeneous cracking of aromatics (see reviews by: Madison and Roberts, 1958;Johns et al, 1962;Fitzer et al, 1971) and of CaO-facilitated reactions of aliphatics below 400 "C. A brief review of the latter is given by Mead (1979). 6 coal over CaO and a temperature range of 425-760 "C produced tars lower in yield and oxygen content and higher in H/C ratio than those from pyrolysis in the presence of sand.…”

mentioning

confidence: 99%

Pyrolysis of volatile aromatic hydrocarbons and n-heptane over calcium oxide and quartz

Ellig¹,

Lai²,

Mead³

et al. 1985

Ind. Eng. Chem. Proc. Des. Dev.

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Benzene, toluene, 1-methylnaphthalene, and n-heptane pyrolysis was studied over the temperature range 550-950 OC, by passing the vapor of the pure compound (initial concentration 2.4-3.9 mol % in helium) through -5.5 cm deep packed beds of calcium oxide/quartz mixtures, or of quartz in control experiments. The total pressure was -1 atm, and contact times were 0.9-1.3 s. The calcium oxide significantly increased the rates and extents of pyrolysis of the aromatics, reducing the temperature for a given percentage conversion by around 140, 140, and 170 OC for benzene, toluene, and 1-methylnaphthalene, respectively. In contrast, CaO decreased the comparable temperature for the aliphatic n-heptane by only -40 'C. Coke was the major product from pyrolysis of the aromatics over both beds. Minor amounts of coke deposition slightly increased the CaO activity for benzene and toluene pyrolysis, but continued coking produced a strong acthmy decay that was fitted to an Elovich model. Oxygen burn-off regenerated 75% and 100% of the initial CaO activity for these two compounds, respectively. A generic stone chemical property, rather than specific BET surface area, is believed responsible for the CaO pyrolysis activity.A shortcut procedure to evaluate the minimum vapor flows in distillation columns with a sidestream stripping section is presented. The method Is simple and highly accurate for relatively ideal mixtures. The case of a ternary mixture is discussed, but the algorithm readily extends to mixtures with any number of components. Also, the approach can be generalized to other types of complex columns as well.

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Pyrolysis of Aromatics and Related Heterocyclics

Cited by 77 publications

References 7 publications

Kinetics and Catalysis of Carbon Gasification

Kinetics and Catalysis of Carbon Gasification

Petroleum Asphaltenes - Part 2: the Effect of Asphaltene and Resin Constituents on Recovery and Refining Processes

Pyrolysis of volatile aromatic hydrocarbons and n-heptane over calcium oxide and quartz

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