A method for separating aromatic hydrocarbons by an extractive distillation, comprising introducing a hydrocarbon mixture containing aromatic hydrocarbons into the middle of an extractive distillation column (8); introducing an extraction solvent into the upper part of the extractive distillation column; after an extractive distillation, a raffinate containing benzene is discharged from the top of the column, wherein the benzene content is 3-40% by mass, and sent to the lower part of the extraction column (10); the extraction solvent is introduced to the upper part of the extraction column for a liquid-liquid extraction; a raffinate liquid free of aromatic hydrocarbons is discharged from the top of the extraction column; a rich solvent containing benzene is discharged from the bottom of the column and enters the upper-middle part of the extractive distillation column; the rich solvent obtained at the bottom of the extractive distillation column is sent to the solvent recovery column to separate the aromatic hydrocarbons and the solvent. By combining an extractive distillation with a liquid-liquid extraction ingeniously, the method can achieve the separation of aromatic hydrocarbons with a high purity and a high recovery rate, and a significant decrease of the energy consumption in the extraction and separation process.

A method for separating aromatic hydrocarbons by an extractive distillation, comprising introducing a hydrocarbon mixture containing aromatic hydrocarbons into the middle of an extractive distillation column (8); introducing an extraction solvent into the upper part of the extractive distillation column; after an extractive distillation, a raffinate containing benzene is discharged from the top of the column, wherein the benzene content is 3-40% by mass, and sent to the lower part of the extraction column (10); the extraction solvent is introduced to the upper part of the extraction column for a liquid-liquid extraction; a raffinate liquid free of aromatic hydrocarbons is discharged from the top of the extraction column; a rich solvent containing benzene is discharged from the bottom of the column and enters the upper-middle part of the extractive distillation column; the rich solvent obtained at the bottom of the extractive distillation column is sent to the solvent recovery column to separate the aromatic hydrocarbons and the solvent. By combining an extractive distillation with a liquid-liquid extraction ingeniously, the method can achieve the separation of aromatic hydrocarbons with a high purity and a high recovery rate, and a significant decrease of the energy consumption in the extraction and separation process.

A method for selectively hydrogenating acetylene in a cracked gas from a steam cracking unit for producing olefins may include separating a hydrogenation feed from the cracked gas. The hydrogenation feed may include acetylene, hydrogen, carbon monoxide, and at least one product. The method may further include contacting the hydrogenation feed with an acetylene hydrogenation catalyst, the contacting causing hydrogenation of at least a portion of the acetylene of the hydrogenation feed to produce a hydrogenation effluent. In response to a change in a composition of a feedstock to the steam cracking unit that results in a change in a hydrogen concentration in the hydrogenation feed, the method may further include determining the hydrogen concentration in the hydrogenation feed and increasing or decreasing a temperature of the hydrogenation feed based on the determined hydrogen concentration of the hydrogenation feed.

A method for selectively hydrogenating acetylene in a cracked gas from a steam cracking unit for producing olefins may include separating a hydrogenation feed from the cracked gas. The hydrogenation feed may include acetylene, hydrogen, carbon monoxide, and at least one product. The method may further include contacting the hydrogenation feed with an acetylene hydrogenation catalyst, the contacting causing hydrogenation of at least a portion of the acetylene of the hydrogenation feed to produce a hydrogenation effluent. In response to a change in a composition of a feedstock to the steam cracking unit that results in a change in a hydrogen concentration in the hydrogenation feed, the method may further include determining the hydrogen concentration in the hydrogenation feed and increasing or decreasing a temperature of the hydrogenation feed based on the determined hydrogen concentration of the hydrogenation feed.

Systems and methods for the production of a high purity isoamylene product. The isoamylene in a mixed hydrocarbon stream may initially be converted to TAME via etherification, and a subsequent decomposition of the TAME may result in a high purity isoamylene stream with very low impurities that is suitable for a variety of petrochemical applications, such as for use in the production of fragrances, pesticides, peroxides, polymer antioxidants, UV stabilizers and hydrocarbon resins.

Systems and methods for the production of a high purity isoamylene product. The isoamylene in a mixed hydrocarbon stream may initially be converted to TAME via etherification, and a subsequent decomposition of the TAME may result in a high purity isoamylene stream with very low impurities that is suitable for a variety of petrochemical applications, such as for use in the production of fragrances, pesticides, peroxides, polymer antioxidants, UV stabilizers and hydrocarbon resins.

A method for recovering one or more water immiscible compounds comprising acidifying and disrupting the microbial biomass; heating the acidified, disrupted microbial biomass to form a heated, acidified disrupted microbial biomass; and contacting the heated, acidified, disrupted microbial biomass with a disulfonated surfactant in an amount sufficient to release at least 30% of the one or more water immiscible compounds from the microbial biomass.

A method for recovering one or more water immiscible compounds comprising acidifying and disrupting the microbial biomass; heating the acidified, disrupted microbial biomass to form a heated, acidified disrupted microbial biomass; and contacting the heated, acidified, disrupted microbial biomass with a disulfonated surfactant in an amount sufficient to release at least 30% of the one or more water immiscible compounds from the microbial biomass.

The invention relates to bissilylamino-functionalized conjugated dienes, their preparation and their use in the production of rubbers. Further, the invention relates to rubbers and rubber compositions, and tires produced therefrom. The functionalized conjugated dienes are selected from the group of compounds of formula (Ia), (Ib), (Ic).

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The invention relates to bissilylamino-functionalized conjugated dienes, their preparation and their use in the production of rubbers. Further, the invention relates to rubbers and rubber compositions, and tires produced therefrom. The functionalized conjugated dienes are selected from the group of compounds of formula (Ia), (Ib), (Ic).

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