Abstract: Systems and methods are provided for integration of an aromatic formation process for converting non-aromatic hydrocarbon to an aromatic product and subsequent methylating of a portion of the aromatic product to produce a methylated product, with improvements in the aromatic formation process and/or the methylation process based on integrating portions of the secondary processing trains associated with the aromatic formation process and the methylation process. The aromatic formation process and methylation process can be used, for example, for integrated production of specialty aromatics or gasoline blending components.

Abstract: Methods for the production of para-xylene include flowing a xylenes-containing stream comprising PX, meta-xylene (MX), and ortho-xylene (OX), to a first crystallization stage. In addition, the methods include lowering a temperature of the xylenes-containing stream to below the eutectic point of the xylenes-containing stream within the first crystallization stage to crystallize at least some of the PX and at least some of one of both of the MX and the OX within the xylenes-containing stream. Further, the methods include separating the xylenes-containing stream into a first crystallization effluent stream and a first filtrate stream.

Abstract: This invention is directed to an improvement in the process for the production of alkylaromatic compounds that results in lower levels of residual unreacted materials in the final product. This invention comprises: 1) alkylation of an aromatic compound with an alkylating agent and a catalyst to produce an effluent stream comprising an alkylaromatic compound and unreacted materials; 2) heating the effluent stream; 3) stripping the effluent stream in a stripping device in the presence of steam; 4) separating a stripping stream from the stripping device, the stripping stream rich in unreacted materials; and 5) separating a product stream from the stripping device, the product stream rich in alkylated aromatic compound.

Abstract: A process of producing PX comprising providing a C8+ feedstock, the C8+ feedstock has C8 hydrocarbons and C9+ hydrocarbons, to a crystallization unit under crystallization conditions to produce a PX enriched stream having a PX concentration of at least 99.5 wt % based on the weight of the PX enriched stream, wherein the C8+ feedstock has a PX concentration of at least 70 wt % based on total weight of xylenes in the C8+ feedstock, which the C8+ feedstock having a C9+ hydrocarbons concentration in a range from 1 wppm to 10 wt % based on the total weight of the C8+ feedstock.

Abstract: A process of producing PX comprising providing a C8+ feedstock, the C8+ feedstock has C8 hydrocarbons and C9+ hydrocarbons, to a crystallization unit under crystallization conditions to produce a PX enriched stream having a PX concentration of at least 99.5 wt % based on the weight of the PX enriched stream, wherein the C8+ feedstock has a PX concentration of at least 70 wt % based on total weight of xylenes in the C8+ feedstock, which the C8+ feedstock having a C9+ hydrocarbons concentration in a range from 1 wppm to 10 wt % based on the total weight of the C8+ feedstock.

Abstract: A process of producing PX comprising providing a C8+ feedstock, the C8+ feedstock has C8 hydrocarbons and C9+ hydrocarbons, to a crystallization unit under crystallization conditions to produce a PX enriched stream having a PX concentration of at least 99.5 wt % based on the weight of the PX enriched stream, wherein the C8+ feedstock has a PX concentration of at least 70 wt % based on total weight of xylenes in the C8+ feedstock, which the C8+ feedstock having a C9+ hydrocarbons concentration in a range from 1 wppm to 10 wt % based on the total weight of the C8+ feedstock.

Abstract: A method including carrying out adiabatic cooling and evaporation operation of a coolant in a crystallizer (20) for a mixture solution of a target organic compound containing the coolant; taking out crystal slurry produced by the operation from the crystallizer (20); pressurizing evaporated vapor to a pressure higher than the operation pressure in the crystallizer (20) by a compressor (30) and then introducing the vapor to an absorption condenser (10); cooling for condensation the mixture solution of organic compound and the evaporated vapor that has been pressurized while allowing them to contact each other in the absorption condenser (10); introducing the crystal slurry taken out of the crystallizer (20) to a purification means (70) for purification of the crystal; and introducing a clarified liquid in the purification means (70) to at least one of the crystallizer (20) and the absorption condenser (10).

Abstract: A process of producing PX comprising providing a C8+ feedstock, the C8+ feedstock has C8 hydrocarbons and C9+ hydrocarbons, to a crystallization unit under crystallization conditions to produce a PX enriched stream having a PX concentration of at least 99.5 wt % based on the weight of the PX enriched stream, wherein the C8+ feedstock has a PX concentration of at least 70 wt % based on total weight of xylenes in the C8+ feedstock, which the C8+ feedstock having a C9+ hydrocarbons concentration in a range from 1 wppm to 10 wt % based on the total weight of the C8+ feedstock.

Abstract: High-purity 2,6-dimethylnaphthalene is prepared by (1) subjecting a dimethylnaphthalene isomer mixture rich in 1,5-dimethylnaphthalene, high boiling point materials, unreacted 1,5-dimethyltetralin, and low boiling point materials, which are produced from a dehydrogenation reaction of 1,5-dimethyltetralin, to separation, using a distillation column; subjecting the dimethylnaphthalene mixture separated by the distillation column to liquid state isomerization in the presence of an isomerization catalyst; (3) a first crystallization (melt crystallization process) by cooling the product of liquid state isomerization with a refrigerant without a solvent to form crystals; and (4) a second crystallization (solution crystallization process) of mixing the crystals of the first crystallization step with a solvent to form crystals.

Abstract: A method for separating and purifying 2,6-dimethylnaphthalene, is provided in which 2,6-dimethylnaphthalene of high purity is obtained from a mixture of dimethylnaphthalene isomers with a high yield, by means of a combined process of column melt crystallization and sweating operation.

Abstract: An object of the present invention is to provide a method for manufacturing 2,6-DMN, in which even when a mixture containing DMN isomers which includes 5 wt % or more of 2,7-DMN is used, a highly pure 2,6-DMN can be obtained. The method for manufacturing the highly pure 2,6-dimethylnaphthalene of the present invention comprises performing cooling crystallization of a mixture containing dimethylnaphthalenes which includes 2,6-dimethylnaphthalene, performing solid-liquid separation to obtain a solid component, and washing the solid component using a solvent, wherein the solid-liquid separation performed after the cooling crystallization includes press filtration.

Abstract: Process for the separation of 2,6-dimethylnaphthalene from mixtures containing it, comprising the following operations: crystallization by the addition of a solvent and cooling of the mixture to a temperature higher than the formation value of the first eutectic; removal of the mother liquor by repeated washings; dissolution of the solid obtained; crystallization by cooling; filtration.

Abstract: The present invention provides a method for manufacturing a highly pure 2,6-dimethylnaphthalene having a purity of 99% or more even when a mixture of dimethylnaphthalene isomers containing 5 wt % or more of 2,7-dimethylnaphthalate is used as a feedstock. The method for manufacturing 2,6-dimethylnaphthalene comprises a step of performing crystallization and solid-liquid separation of a liquid primarily containing dimethylnaphthalene isomers so that the liquid is separated into a cake containing the dimethylnaphthalene isomers and a mother liquor, and a step of performing separation/purification of the cake. In the method described above, the crystallization and the solid-liquid separation are performed under the condition in which the ratio of the content of 2,6-dimethylnaphthalene in the mother liquor to that of 2,7-dimethylnaphthalene therein is not less than 1 so that the content of 2,6-dimethylnaphthalene in the cake is 60% or more and that the content of 2,7-dimethylnaphthalene therein is 6.5% or less.

Abstract: A process is described for separating a desired substance from an aggregate mixture in which process a three-phase dispersion is formed, the first phase comprising droplets phase comprising a liquid transport phase, and the third phase comprising a surface upon which the desired substance can crystallize, whereby a chemical potential exists for crystal growth of the desired substance in the third phase thereby creating a flow of the desired substance from the first phase through the second phase to the third phase where the desired substance crystallizes, characterized in that the Gibb's free enthalpy of formation (&Dgr;G) of the droplets is <0.

Abstract: The process for producing crystallisation products with an average particle diameter of <1 .mu.m is based on the atomisation of a solution and the simultaneous evaporation of the solvent. The atomised solution A crystallises in a gas atmosphere, in which it is simultaneously contacted with a cloud of drops 4 of a surfactant-containing liquid B, thus forming an aerosol mixture A, B which is then deposited in the form of a colloidal crystal suspension in which the surfactant-containing liquid B forms the continuous phase. The cloud of drops 4 of the surfactant-containing liquid can also be produced by atomisation.

Abstract: There are disclosed an industrially advantageous process for efficiently producing highly pure 2,6-dimethylnaphthalene (DMN) in high yield from a mixture of DMN by carrying out in turn, the steps of isomerizing a mixture of DMN in the presence of a catalyst; crystallizing the isomerization reaction product in the presence of a solvent (e.g.

Abstract: A process for producing highly pure 2,6-dimethylnaphthalene in a high yield from a mixture of dimethylnaphthalene isomers in the presence of a solvent, such as an aliphatic or alicyclic saturated hydrocarbon. Highly pure 2,6-dimethylnaphthalene can be produced steadily for a long time by filtering the 2,6-dimethylnaphthalene crystal precipitated by the crystallizing by using a filtration apparatus, such as a rotary vacuum filter, peeling-off the filtered cake from a filter cloth and cleaning the filter cloth with a solvent, at a temperature not lower than a filtration temperature.

Abstract: A method for accelerating the solidification rate of low melting products is disclosed. The method of the invention comprises the atomization of a molten low-melting product within a fluid stream which greatly enhances the rate at which the low-melting product solidifies.

Abstract: This invention is a crystallization process for p-xylene recovery. A single temperature crystallization stage is used for producing p-xylene from a feed having an above equilibrium p-xylene concentration, such as from toluene disproportionation.

Abstract: Process for separating and purifying substances by crystallization from the melt under high pressuresIn the process for separating or purifying substances by crystallization from melts or highly concentrated solutions under high pressures, gas is dissolved in the melt to be crystallized and is expelled again after the crystallization with reduction in the pressure. Still adhering or occluded impurities are thus removed.

Abstract: In the process for separating and purifying substances by crystallization from the melt under pressure, the melt is subjected to pressure under an inert gas atmosphere and then cooled, whereupon it crystallizes. The residual melt is separated from the resulting crystals, after which the crystals are degassed by reducing the pressure and are caused to sweat, and the sweat oil is separated off.

Abstract: Adiabatic self-evaporation cooling of a refrigerant is performed in a crystallizer for a treated organic matter which contains the refrigerant and is fed into the crystallizer. Crystals produced by the adiabatic self-evaporation cooling are withdrawn from the crystallize. An evaporated vapor is introduced from the crystallizer into an absorber so as to be contacted with a concentrated solution transformed from a generator for condensation in the absorber. A condensate is introduced from the absorber into the generator, the refrigerant is evaporated in the generator, an evaporated vapor is introduced from the generator to the condenser, the evaporated vapor is condensed in the condenser, a condensate is supplied from the condenser to the crystallizer and the concentrated solution is circulated between the absorber and the generator by returning the concentrated solution, in which the concentration of an absorbent is increased by the generator to the absorber.

Abstract: A process for purifying 1,1,3,4,4,6-hexamethyltetralin is disclosed comprising melting crude 1,1,3,4,4,6-hexamethyltetralin in methanol with heating, cooling the resulting suspension, and adding seed crystals at a temperature of 45.degree.-60.degree. C.; as well as a process for purifying 1,1,3,4,4,6-hexamethyltetralin comprising recrystallizing crude 1,1,3,4,4,6-hexamethyltetralin from a mixed solvent of methanol and a solvent capable of easily dissolving 1,1,3,4,4,6-hexamethyltetralin, the proportion of this solvent being 10 to 25% by weight based on the weight of methanol. These processes make it possible to obtain 1,1,3,4,4,6-hexamethyltetralin of high purity easily with high recovery by purifying crude 1,1,3,4,4,6-hexamethyltetralin.

Abstract: Separation of a crystallizable component, especially paraxylene, from solution by chilling to form a slurry of crystals and liquid, separating crystals of the component in a first separator while simultaneously washing the crystals with a wash liquid and then re-melting the crystals, re-chilling them, separating the crystals in a second separator and washing them with a second wash liquid.

Abstract: This process is an improvement of a process described in German Open Patent Application No. 3703646 for obtaining a p-xylene product with a purity of at least 99.5%. The inert fluid used as a cold carrier is mixed with a crude product starting material, which has a high p-xylene content, in a mixing vessel under rotation to form a resultant mixture. Subsequently the resultant mixture is concentrated to a crystal content of from 30% to 70% and after that the p-xylene crystals are separated in a separator. The purity of the product p-xylene can be increased by heating these crystals in the separator.

Abstract: Method and apparatus for separating and/or purifying a substance from a molten mixture by crystallization, in which the molten mixture is conducted into an annular space defined by two substantially curvilinearly-shaped surfaces, one of the surfaces being cooled, and at least one of the surfaces rotating. The molten mixture is thereby cooled as the same flows through the annular space with material crystallizing to form a deposit upon the cooled surface. The crystallized deposit is then caused to be contacted by a source of heat, whereby the same is melted. At least part of the melted deposit is then removed from the annular space, to obtain the substance in purified form, while any remaining part of the melted deposit is conducted through the annular space in a direction away from the source of heat. Non-crystallized molten material which contains impurities is also removed from within the annular space.

Abstract: A process and an apparatus therefor are described for separating p-xylene from a p-xylene containing hydrocarbon liquid feed material by crystallization, said process comprising (1) mixing a p-xylene containing hydrocarbon feed material with an inert liquid refrigerant, (2) feeding the mixed liquid into a lower part of a bubble tower type crystallization tower as an ascending current, (3) evaporating the refrigerant by the lowering of the liquid static pressure caused by ascent of the mixed liquid and by the transfer of heat into the refrigerant due to solidification of p-xylene and by the lowering of the temperature of the mixed liquid, cooling the ascending liquid to form a slurry of p-xylene crystals in the hydrocarbon liquid, (4) separating the inert refrigerant as a vapor from the liquid surface of the upper part of the crystallization zone, and (5) separating p-xylene crystals from the slurry discharged from the upper part of the crystallization zone.

Abstract: Anthracene is precipitated in improved purity and yield by cooling a creosote coal tar distillation fraction. A ketone such as acetone is added to the fraction before the anthracene precipitates. The ketone retains phenanthrene and/or carbazole in the liquid phase as the anthracene precipitates. If the ketone is then removed, the phenanthrene and/or carbazole precipitates and can also be purified.