This invention relates to an alkylating process for alkyl benzenes, including the steps of: a) an alkyl benzene and a first stream of alkylating agent being fed into a first reaction zone, contacting with a catalyst A, to produce a process stream I; b) the process stream I and a second stream of alkylating agent being fed into at least one second reaction zone, contacting with a catalyst B, to produce a process stream II; and c) the process stream II being fed into at least one third reaction zone, contacting with a catalyst C, to produce a process stream III containing an alkylate. The present alkylating process can improve the utilization efficiency of the alkylating agent.

The present invention provides an improved catalyst and a method for its manufacture. The catalyst comprises an acidic, porous crystalline material and has a Proton Density Index of greater than about 1.0, for example from greater than 1.0 to about 2.0, e.g. from about 1.01 to about 1.85. This catalyst may be used to effect conversion in chemical reactions, and is particularly useful in a process for selectively producing a monoalkylated aromatic compound comprising the step of contacting an alkylatable aromatic compound with an alkylating agent under at least partial liquid phase conditions. The acidic, porous crystalline material of the catalyst may comprise an acidic, crystalline molecular sieve having the structure of zeolite Beta, an MWW structure type material, e.g. MCM-22, MCM-36, MCM-49 MCM-56, or a mixture thereof.

The present invention provides an improved catalyst and a method for its manufacture. The catalyst comprises an acidic, porous crystalline material and has a Proton Density Index of greater than about 1.0, for example from greater than 1.0 to about 2.0, e.g. from about 1.01 to about 1.85. This catalyst may be used to effect conversion in chemical reactions, and is particularly useful in a process for selectively producing a monoalkylated aromatic compound comprising the step of contacting an alkylatable aromatic compound with an alkylating agent under at least partial liquid phase conditions. The acidic, porous crystalline material of the catalyst may comprise an acidic, crystalline molecular sieve having the structure of zeolite Beta, an MWW structure type material, e.g. MCM-22, MCM-36, MCM-49 MCM-56, or a mixture thereof.

Provided is a mononuclear ruthenium complex that comprises a ruthenium-silicon bond that is represented by formula (1) and that exhibits excellent catalyst activity in each of a hydrosilylation reaction, a hydrogenation reaction, and reduction of a carbonyl compound. ##STR00001## In formula (1), R.sup.1-R.sup.6 either independently represent an alkyl group, an aryl group, an aralkyl group or the like that may be substituted with a hydrogen atom or X, or represent a crosslinking substituent in which at least one pair comprising one of R.sup.1-R.sup.3 and one of R.sup.4-R.sup.6 is combined. X represents a halogen atom, an organoxy group, or the like. L represents a two-electron ligand other than CO and phosphine. When a plurality of L are present, the plurality of L may be the same as or different from each other. When two L are present, the two L may be bonded to each other. n and m independently represent an integer of 1 to 3 with the stipulation that n+m equals 3 or 4.

Provided is a mononuclear ruthenium complex that comprises a ruthenium-silicon bond that is represented by formula (1) and that exhibits excellent catalyst activity in each of a hydrosilylation reaction, a hydrogenation reaction, and reduction of a carbonyl compound. ##STR00001## In formula (1), R.sup.1-R.sup.6 either independently represent an alkyl group, an aryl group, an aralkyl group or the like that may be substituted with a hydrogen atom or X, or represent a crosslinking substituent in which at least one pair comprising one of R.sup.1-R.sup.3 and one of R.sup.4-R.sup.6 is combined. X represents a halogen atom, an organoxy group, or the like. L represents a two-electron ligand other than CO and phosphine. When a plurality of L are present, the plurality of L may be the same as or different from each other. When two L are present, the two L may be bonded to each other. n and m independently represent an integer of 1 to 3 with the stipulation that n+m equals 3 or 4.

Provided is a mononuclear ruthenium complex that comprises a ruthenium-silicon bond that is represented by formula (1) and that exhibits excellent catalyst activity in each of a hydrosilylation reaction, a hydrogenation reaction, and reduction of a carbonyl compound. ##STR00001## In formula (1), R.sup.1-R.sup.6 either independently represent an alkyl group, an aryl group, an aralkyl group or the like that may be substituted with a hydrogen atom or X, or represent a crosslinking substituent in which at least one pair comprising one of R.sup.1-R.sup.3 and one of R.sup.4-R.sup.6 is combined. X represents a halogen atom, an organoxy group, or the like. L represents a two-electron ligand other than CO and phosphine. When a plurality of L are present, the plurality of L may be the same as or different from each other. When two L are present, the two L may be bonded to each other. n and m independently represent an integer of 1 to 3 with the stipulation that n+m equals 3 or 4.

A process for the distillative separation of ethylbenzene from a mixture comprising ethylbenzene and at least one other C8 aromatic compound, comprising introducing a feed stream comprising said mixture into a first distillation column, introducing a first stream comprising a heavy solvent above the feed stream into the first distillation column, introducing an aqueous stream below the feed stream into the first distillation column.

A process for the distillative separation of ethylbenzene from a mixture comprising ethylbenzene and at least one other C8 aromatic compound, comprising introducing a feed stream comprising said mixture into a first distillation column, introducing a first stream comprising a heavy solvent above the feed stream into the first distillation column, introducing an aqueous stream below the feed stream into the first distillation column.

A process for the distillative separation of ethylbenzene from a mixture comprising ethylbenzene and at least one other C8 aromatic compound, comprising introducing a feed stream comprising said mixture into a first distillation column, introducing a first stream comprising a heavy solvent above the feed stream into the first distillation column, introducing an aqueous stream below the feed stream into the first distillation column.

The present disclosure relates to a method for treating a catalyst that is useful for producing mono-alkylaromatic compounds, the method comprises the steps of (a) contacting the untreated catalyst with water to produce water-contacted catalyst, and (b) drying the water-contacted catalyst with a drying gas without steam being formed at a temperature of less than 300° C. to produce a treated catalyst. The treatment is effective to improve the activity and catalyst selectivity. A process for producing a mono-alkylaromatic compound comprising such a catalyst treatment is also disclosed.