Extractive distillation of benzene, toluene, and xylenes from pyrolysis gasoline using methylsulfonylethane as a cosolvent

The conversion of n-heptanes into aromatic hydrocarbons benzene, toluene and xylenes (BTX), by the chromatographic pulse method in the temperature range of 673 - 823K was performed over the HZSM-5 and Ag-HZSM-5 zeolites modified by ion exchange with AgNO3 aqueous solutions. The catalysts, HZSM-5 (SiO2/Al2O3 = 33.9), and Ag-HZSM-5 (Ag1-HZSM-5 wt. % Ag1.02, Ag2-HZSM-5 wt. % Ag 1.62; and Ag3-HZSM-5 wt. % Ag 2.05 having different acid strength distribution exhibit a conversion and a yield of aromatics depending on temperature and metal content. The yield of aromatic hydrocarbons BTX appreciably increased by incorporating silver cations Ag+ into HZSM-5.

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Fate of Toxic Organic Compounds in Activated Sludge and Integrated PAC Systems

Water Science & Technology ◽

10.2166/wst.1987.0227 ◽

1987 ◽

Vol 19 (3-4) ◽

pp. 471-482 ◽

Cited By ~ 19

Author(s):

W. J. Weber ◽

B. E. Jones ◽

L. E. Katz

Keyword(s):

Activated Carbon ◽

Activated Sludge ◽

Organic Compounds ◽

Powdered Activated Carbon ◽

Carbon Adsorption ◽

Powdered Carbon ◽

Benzene Toluene ◽

Adsorptive Properties ◽

Carbon Concentrations ◽

Toxic Organic Compounds

The addition of powdered activated carbon (PAC) to activated sludge treatment systems to enhance removal of specific toxic organic compounds from wastewater was evaluated. Nine organic compounds encompassing a range of solubility, volatility, biodegradability, and adsorptive properties were studied. Kate and equilibrium investigations were conducted to quantify the removal mechanisms of volatilization, biodegradation, biosorption, and carbon adsorption. Results from steady-state bioreactor studies showed that the addition of less than 100 mg/ℓ powdered activated carbon to the influent did not enhance the removal of the biodegradable target compounds investigated: benzene, toluene, ethylbenzene, o-xylene, chlorobenzene, and nitrobenzene. Significantly improved removals of the poorly degradable and non-biodegradable compounds 1,2-dichlorobenzene, 1,2,4-trichlorobenzene, and lindane occurred at influent powdered carbon concentrations in the 12.5 to 25 mg/ℓ range. Influent powdered carbon concentrations of 100 mg/ℓ effected overall removals of greater than 90%. The addition of powdered activated carbon not only reduced effluent concentrations but also reduced the amounts of the volatile compounds stripped to the atmosphere.

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Liquid-liquid equilibrium in binary glycols-toluene and glycols-xylene systems

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19821686 ◽

1982 ◽

Vol 47 (6) ◽

pp. 1686-1694 ◽

Cited By ~ 14

Author(s):

Lumír Mandík ◽

František Lešek

Keyword(s):

Atmospheric Pressure ◽

Binary Systems ◽

Liquid Equilibrium ◽

Benzene Toluene

Liquid-liquid equilibria were determined in the following binary systems: 1,2-ethandiol/toluene, 1,2-ethandiol/xylene, 1,2-propandiol/toluene, 1,2-propandiol/xylene, 1,4-butandiol/toluene, 1,4-butandiol/xylene, 1,3-butandiol/toluene, 1,3-butandiol/xylene, 1,3-butandiol/p-xylene, 2,2'-dioxydiethanol/toluene, 2,2'-dioxydiethanol/xylene. The solubility of 2,2-dimethyl-1,3-propandiol in benzene, toluene and xylene was also measured. Critical solubility temperatures at atmospheric pressure were determined for systems containing 1,2-propandiol and 1,3-butandiol.

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Mechanistische Untersuchungen zum reversiblen Gleichgewicht von metallorganischen Tripeldecker- und Sandwichkomplexen des Typs [Bis{(η5-CpR)Co}-μ-{η4:η4-aren}] und [(η5-CpR)Co(η6-aren)] / Mechanistic Studies towards the Reversible Equilibrium between Metal Organic Triple Decker and Sandwich Complexes [Bis{(η5 -CpR)Co}-μ-{η4 :η4-arene}] and [{(η5-CpR)Co(η6-arene)]

Zeitschrift für Naturforschung B ◽

10.1515/znb-1998-1105 ◽

1998 ◽

Vol 53 (11) ◽

pp. 1267-1272 ◽

Cited By ~ 8

Author(s):

Jörg J. Schneider ◽

Dirk Wolf

Keyword(s):

Ligand Exchange ◽

Sandwich Complexes ◽

Valuable Metal ◽

H Nmr ◽

Synthetic Utility ◽

Metal Organic ◽

Arene Ligand ◽

Benzene Toluene

The arene ligand exchange mechanism of slipped arene triple deckers [Bis{(η5-CpR)Co}-μ-{η4:η4-arene}] (R = Me5, 1,2,4 tri-tert butyl, arene = benzene, toluene) 1 was studied by 1H-NMR spectroscopy for different concentrations and solvents. It has been found that triple deckers of type 1 decompose slowly in solution. A unique equilibrium, between these triple deckers and the mixed sandwich complexes [(η6-arene)Co(η5-CpR)] and 14 e [(η5-Cp)Co]solv fragments generated in situ by decomposition o f 1 exists. In addition to this equilibrium arene lability of the thus formed mixed sandwich complex type has been detected by NMR making slipped triple deckers 1 ideal single source compounds for the generation of two [(η5-Cp)Co] fragments in one reaction step. Such fragments are valuable metal ligand components with high synthetic utility in organometallic chemistry.

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Polymer composites as sensing materials for liquid organic solvents – preliminary results

e-Polymers ◽

10.1515/epoly.2011.11.1.362 ◽

2011 ◽

Vol 11 (1) ◽

Cited By ~ 1

Author(s):

Stanislaw Frackowiak ◽

Monika Maciejewska ◽

Andrzej Szczurek ◽

Marek Kozlowski

Keyword(s):

Electrical Resistivity ◽

Carbon Black ◽

Polymer Composites ◽

Percolation Theory ◽

Liquid Mixtures ◽

Organic Liquids ◽

Volumetric Fraction ◽

Factors Influencing ◽

Benzene Toluene ◽

Main Factors

AbstractCarbon black-filled polymer composites were investigated as sensing materials for organic liquids. Polypropylene and polystyrene which were selected as matrices and various amounts of carbon black were considered as the main factors influencing sensitivity of the composites in view of the percolation theory. Disposable filaments were produced of these materials. Change in their electrical resistivity was measured upon immersion in benzene, toluene, xylene, ethylbenzene and their mixtures. It has been found that studied materials were sensitive to the composition of liquid mixtures of organic solvent. Relationships between the filament response and volumetric fraction of the components were presented. The studied materials have shown promising sensing properties, which suggest their applicability for identification and quantification of multicomponent organic liquids.

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Chemical Recycling of WEEE Plastics—Production of High Purity Monocyclic Aromatic Chemicals

Processes ◽

10.3390/pr9030530 ◽

2021 ◽

Vol 9 (3) ◽

pp. 530

Author(s):

Tobias Rieger ◽

Jessen C. Oey ◽

Volodymyr Palchyk ◽

Alexander Hofmann ◽

Matthias Franke ◽

...

Keyword(s):

High Purity ◽

Fractional Distillation ◽

Gas Chromatography Mass Spectrometry ◽

Thermochemical Conversion ◽

Chemical Recycling ◽

Pyrolysis Oil ◽

X Ray ◽

Benzene Toluene ◽

Halogen Content ◽

Methyl Styrene

More than 200 kg real waste electrical and electronic equipment (WEEE) shredder residues from a German dismantling plant were treated at 650 °C in a demonstration scale thermochemical conversion plant. The focus within this work was the generation, purification, and analysis of pyrolysis oil. Subsequent filtration and fractional distillation were combined to yield basic chemicals in high purity. By means of fractional distillation, pure monocyclic aromatic fractions containing benzene, toluene, ethylbenzene, and xylene (BTEX aromatics) as well as styrene and α-methyl styrene were isolated for chemical recycling. Mass balances were determined, and gas chromatography–mass spectrometry (GC-MS) as well as energy dispersive X-ray fluorescence (EDXRF) measurements provided data on the purity and halogen content of each fraction. This work shows that thermochemical conversion and the subsequent refining by fractional distillation is capable of recycling WEEE shredder residues, producing pure BTEX and other monocyclic aromatic fractions. A significant decrease of halogen content (up to 99%) was achieved with the applied methods.

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