Abstract:
Processes and apparatuses for producing para-xylenes are provided. The processes comprises providing a hydrocarbon stream comprising C7+ hydrocarbons. The hydrocarbon stream is separated to provide a C8 aromatics stream and an ortho-xylene rich stream. The C8 aromatics stream is passed to a para-xylene separation unit for separating para-xylene to provide a para-xylene stream and a raffinate stream. At least a portion of the raffinate stream is passed to a first isomerization unit to provide a first isomerization effluent, wherein the first isomerization effluent is produced in the presence of an ethylbenzene (EB) isomerization catalyst. At least a portion of the ortho-xylene rich stream is contacted with an isomerization catalyst in a second isomerization unit in liquid phase at isomerization conditions in substantial absence of hydrogen to produce a second isomerization effluent.
Abstract:
A process for converting polycyclic aromatic compounds to monocyclic aromatic compounds includes pyrolyzing a coal feed to produce a coke stream and a coal tar stream. The coal tar stream is cracked, and the cracked coal tar stream is fractionated to produce an aromatic fraction comprising the polycyclic aromatic compounds. The process further includes hydrocracking the aromatic fraction to partially hydrogenate at least a first portion of the aromatic fraction, and to open at least one ring of a second portion of the aromatic fraction to form the monocyclic aromatic compounds from the polycyclic compounds, and recycling the first portion of the aromatic fraction.
Abstract:
A process for selectively dealkylating aromatic compounds includes providing a coal tar stream comprising aromatic compounds and hydrotreating the coal tar stream to reduce a concentration of one or more of organic sulfur, nitrogen, and oxygen in the coal tar stream, and to hydrogenate at least a portion of the aromatic compounds in the coal tar stream. The process further includes hydrocracking the hydrotreated coal tar stream to further hydrogenate the aromatic compounds and to crack at least one ring of multi-ring aromatic compounds to form single-ring aromatic compounds. The single-ring aromatic compounds present in the hydrocracked stream are then dealkylated to remove alkyl groups containing two or more carbon atoms.
Abstract:
A process for producing alkylated aromatic compounds includes pyrolyzing a coal feed to produce a coke stream and a coal tar stream. The coal tar stream is hydrotreated and the resulting hydrotreated coal tar stream is cracked. A portion of the cracked coal tar stream is separated to obtain a fraction having an initial boiling point in the range of about 60° C. to about 180° C., and an aromatics-rich hydrocarbon stream is extracted by contacting the fraction with one or more solvents. The aromatics-rich hydrocarbon stream is contacted with an alkylating agent to produce an alkylated aromatic stream, or the aromatics-rich hydrocarbon stream is reacted with an aliphatic compound or methanol in the presence of a catalyst to produce a methylated aromatic stream. The alkylated aromatic stream, the methylated aromatic stream, or both are separated into at least a benzene stream, a toluene stream, and a xylenes stream.
Abstract:
A process for producing hydrogen-rich coal tar includes introducing a coal feed into a pyrolysis zone, and contacting the coal feed with a hydrogen donor stream and a multifunctional catalyst in the pyrolysis zone. The multifunctional catalyst includes a hydrogenation function for increasing a hydrogen content of said coal tar stream. The process further includes pyrolyzing the coal feed with the hydrogen donor stream and the multifunctional catalyst to produce a coke stream and a coal tar stream comprising hydrocarbon vapor.
Abstract:
A process for pyrolyzing coal using a recycled hydrogen donor includes introducing a coal feed to a pyrolysis zone and heating the coal feed to a temperature of about 300° C. in the absence of hydrogen. A hydrogen donor solvent is introduced to the pyrolysis zone after the coal feed is heated to about 300° C., and the temperature of the coal feed and the hydrogen donor solvent is increased to about 475° C., while increasing a pressure in the pyrolysis zone to at or above a vapor pressure of the hydrogen donor solvent. At least an aromatic hydrocarbon rich fraction is separated from the coal tar stream and hydrogenated. The hydrogenated aromatic hydrocarbon rich fraction is recycled to the pyrolysis zone as the hydrogen donor solvent.
Abstract:
A process for purifying at least one product from coal tar is described. The process involves separating a coal tar fraction having a boiling point in the range of about 180° C. to about 230° C. into an acidic portion and a non-acidic portion by contacting the fraction with a caustic compound. The acidic portion is separated into a cresol portion and a xylenol portion, and the non-acidic portion is separated into a naphthalene portion and a naphthalene co-boiler portion. The acidic portion and the non-acidic portions are separated by contacting with an adsorbent comprising small, discrete crystallites, the adsorbent having less than 10 wt % amorphous binder component. The various portions can be separated in a similar manner.
Abstract:
A method of processing a coal feed to produce aromatic hydrocarbon compounds includes providing a coal tar stream and converting the coal tar stream to a conversion product comprising at least olefins, paraffins, and aromatics. The process further includes separating the olefins and C5− paraffins from the conversion product, and contacting the separated olefins and the C5− paraffins with a catalyst to dehydrogenize, oligomerize, and cyclize the olefins and the C5− paraffins, to form aromatic hydrocarbon compounds.
Abstract:
A method of processing a coal feed to produce aromatic hydrocarbon compounds includes providing a coal tar stream and converting the coal tar stream to a conversion product comprising at least olefins, paraffins, and aromatics. The process further includes separating the olefins and C5− paraffins from the conversion product, and contacting the separated olefins and the C5− paraffins with a catalyst to dehydrogenize, oligomerize, and cyclize the olefins and the C5− paraffins, to form aromatic hydrocarbon compounds.
Abstract:
A process for selectively dealkylating aromatic compounds includes providing a coal tar stream comprising aromatic compounds and hydrotreating the coal tar stream to reduce a concentration of one or more of organic sulfur, nitrogen, and oxygen in the coal tar stream, and to hydrogenate at least a portion of the aromatic compounds in the coal tar stream. The process further includes hydrocracking the hydrotreated coal tar stream to further hydrogenate the aromatic compounds and to crack at least one ring of multi-ring aromatic compounds to form single-ring aromatic compounds. The single-ring aromatic compounds present in the hydrocracked stream are then dealkylated to remove alkyl groups containing two or more carbon atoms.