Embodiments in accordance with the present invention encompass an organoruthenium compound of the formula (I) or formula (II): ##STR00001##
Wherein X, L, R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, Ar.sub.1 and Ar.sub.2 are as defined herein. Also disclosed herein are the use of organoruthenium compound of formula (I) or formula (II) as (pre)catalysts for the olefin metathesis reactions, as well as to the process for carrying out the olefin metathesis reaction.

Embodiments in accordance with the present invention encompass an organoruthenium compound of the formula (I) or formula (II): ##STR00001##
Wherein X, L, R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, Ar.sub.1 and Ar.sub.2 are as defined herein. Also disclosed herein are the use of organoruthenium compound of formula (I) or formula (II) as (pre)catalysts for the olefin metathesis reactions, as well as to the process for carrying out the olefin metathesis reaction.

Methods and phosphorus-containing solid catalysts for catalyzing dehydration of cyclic ethers (e.g., furans, such as 2,5-dimethylfuran) and alcohols (e.g., ethanol and isopropanol). The alcohols and cyclic ethers may be derived from biomass. One example includes a tandem Diels-Alder cycloaddition and dehydration of biomass-derived 2,5-dimethyl-furan and ethylene to renewable p-xylene. The phosphorus-containing solid catalysts are also active and selective for dehydration of alcohols to alkenes.

Methods and phosphorus-containing solid catalysts for catalyzing dehydration of cyclic ethers (e.g., furans, such as 2,5-dimethylfuran) and alcohols (e.g., ethanol and isopropanol). The alcohols and cyclic ethers may be derived from biomass. One example includes a tandem Diels-Alder cycloaddition and dehydration of biomass-derived 2,5-dimethyl-furan and ethylene to renewable p-xylene. The phosphorus-containing solid catalysts are also active and selective for dehydration of alcohols to alkenes.

Methods and phosphorus-containing solid catalysts for catalyzing dehydration of cyclic ethers (e.g., furans, such as 2,5-dimethylfuran) and alcohols (e.g., ethanol and isopropanol). The alcohols and cyclic ethers may be derived from biomass. One example includes a tandem Diels-Alder cycloaddition and dehydration of biomass-derived 2,5-dimethyl-furan and ethylene to renewable p-xylene. The phosphorus-containing solid catalysts are also active and selective for dehydration of alcohols to alkenes.

Disclosed is a method for providing improved hydrogenation activity by pretreating a catalyst in a three-step manner before selective hydrogenation of unsaturated hydrocarbons in an aromatic fraction in the presence of an oxide-type bimetallic (particularly nickel-molybdenum) supported catalyst.

Disclosed is a method for providing improved hydrogenation activity by pretreating a catalyst in a three-step manner before selective hydrogenation of unsaturated hydrocarbons in an aromatic fraction in the presence of an oxide-type bimetallic (particularly nickel-molybdenum) supported catalyst.

A method of producing p-xylene comprising the steps of separating the reformate feed in the reformate splitter to produce a benzene stream, a combined heavy stream, a xylene stream, and a toluene stream, converting the C9+ aromatic hydrocarbons in the presence of a dealkylation catalyst in the dealkylation reactor to produce a dealkylation effluent, separating the dealkylation effluent in the dealkylation splitter to produce a C9 stream and a C10+ stream, reacting the C9 stream, the toluene stream, the benzene stream, and the hydrogen stream in the presence of a transalkylation catalyst in the transalkylation reactor to produce a transalkylation effluent, separating the p-xylenes from the xylene stream in the p-xylene separation unit to produce a p-xylene product and a p-xylene depleted stream, converting the m-xylene and o-xylene in the p-xylene depleted stream in the isomerization unit to produce an isomerization effluent.

A process is described for producing cumene comprising contacting benzene and a C3 alkylating agent under alkylation conditions with an alkylation catalyst in an alkylation zone to produce an alkylation effluent comprising cumene and alkylaromatic compounds heavier than cumene. Cumene is recovered from the alkylation effluent to leave a byproduct stream containing the alkylaromatic compounds heavier than cumene, which is separated into a polyisopropylbenzene-containing stream, an aromatic overhead stream, and a bottoms product. At least part of the aromatic overhead stream is recycled to the alkylation zone to reduce raw material consumption and improve cumene yield.

A process is described for producing cumene comprising contacting benzene and a C3 alkylating agent under alkylation conditions with an alkylation catalyst in an alkylation zone to produce an alkylation effluent comprising cumene and alkylaromatic compounds heavier than cumene. Cumene is recovered from the alkylation effluent to leave a byproduct stream containing the alkylaromatic compounds heavier than cumene, which is separated into a polyisopropylbenzene-containing stream, an aromatic overhead stream, and a bottoms product. At least part of the aromatic overhead stream is recycled to the alkylation zone to reduce raw material consumption and improve cumene yield.