The present application discloses a polyhydroxy aromatic intermediate, preparation thereof and use thereof in a polycondensate water-reducer with branched side chains. The polycondensate water-reducer with branched side chains has a branched side chain structure which provides a stronger steric hindrance. The synergistic effect of the branched side chains and the rigid skeleton of the aromatic ring greatly improves the water-reducing ability. Especially under a condition of low water/cement ratio, the improvement in water-reducing ability is more obvious. The branched polyether side chain is more conducive to the formation of a thicker water film layer, which has an obvious viscosity reduction effect. The conformation of the branched polyether side chain is less affected by different ionic environments in the pore solution in cement, and thus has a stronger adaptability to various raw materials. The water-reducer is suitable for the preparation of high-strength concrete, self-compacting concrete and concrete with low water-to-binder ratio and high volume of mineral admixtures, especially for the preparation of concrete containing machine-made sand.

The present application discloses a polyhydroxy aromatic intermediate, preparation thereof and use thereof in a polycondensate water-reducer with branched side chains. The polycondensate water-reducer with branched side chains has a branched side chain structure which provides a stronger steric hindrance. The synergistic effect of the branched side chains and the rigid skeleton of the aromatic ring greatly improves the water-reducing ability. Especially under a condition of low water/cement ratio, the improvement in water-reducing ability is more obvious. The branched polyether side chain is more conducive to the formation of a thicker water film layer, which has an obvious viscosity reduction effect. The conformation of the branched polyether side chain is less affected by different ionic environments in the pore solution in cement, and thus has a stronger adaptability to various raw materials. The water-reducer is suitable for the preparation of high-strength concrete, self-compacting concrete and concrete with low water-to-binder ratio and high volume of mineral admixtures, especially for the preparation of concrete containing machine-made sand.

A method and system for preparing epoxypropane by direct epoxidation of propylene includes the steps of subjecting a mixed gas of a first feed gas and a second feed gas to a contact reaction with a catalyst under reaction conditions of propylene epoxidation to prepare epoxypropane. The first feed gas contains oxygen gas and is free or substantially free of hydrogen gas. The second feed gas contains hydrogen gas and is free or substantially free of oxygen gas. The first feed gas and/or the second feed gas contain propylene, at least one of the first feed gas and the second feed gas further contains a diluent gas. The method can be used for reducing dosage of diluent gas, preferably recycling the tail gas, thereby significantly increasing the conversion rate of propylene without compromising the service life of catalyst.

A method and system for preparing epoxypropane by direct epoxidation of propylene includes the steps of subjecting a mixed gas of a first feed gas and a second feed gas to a contact reaction with a catalyst under reaction conditions of propylene epoxidation to prepare epoxypropane. The first feed gas contains oxygen gas and is free or substantially free of hydrogen gas. The second feed gas contains hydrogen gas and is free or substantially free of oxygen gas. The first feed gas and/or the second feed gas contain propylene, at least one of the first feed gas and the second feed gas further contains a diluent gas. The method can be used for reducing dosage of diluent gas, preferably recycling the tail gas, thereby significantly increasing the conversion rate of propylene without compromising the service life of catalyst.

A process for producing isomerized olefins, branched aldehydes, branched alcohols, branched surfactants and other branched derivatives through isomerization, hydroformylation, hydrogenation, surfactant forming reactions and other derivative forming reactions.

A process for producing isomerized olefins, branched aldehydes, branched alcohols, branched surfactants and other branched derivatives through isomerization, hydroformylation, hydrogenation, surfactant forming reactions and other derivative forming reactions.

A polyalkylene glycol-based compound of formula (1):

##STR00001##

may be one in which R.sup.1 is a monovalent hydrocarbon group having 1 to 32 carbon atoms, a monovalent aromatic hydrocarbon group having 6 to 42 ring carbon atoms, a monovalent acyl group having 2 to 32 carbon atoms, or a monovalent oxygen-containing hydrocarbon group having 2 to 32 carbon atoms; R.sup.2 is a monovalent hydrocarbon group having 1 to 32 carbon atoms, a monovalent aromatic hydrocarbon group having 6 to 42 ring carbon atoms, a monovalent acyl group having 2 to 32 carbon atoms, a monovalent oxygen-containing hydrocarbon group having 2 to 32 carbon atoms, or a hydrogen atom; R.sup.3 is a divalent hydrocarbon group having 4 carbon atoms; R.sup.4 is a divalent hydrocarbon group having 2 or 3 carbon atoms; m and n are respectively numbers between 1 and 40 and 0 and 20; and m/(m+n)≥0.5.

A polyalkylene glycol-based compound of formula (1):

##STR00001##

may be one in which R.sup.1 is a monovalent hydrocarbon group having 1 to 32 carbon atoms, a monovalent aromatic hydrocarbon group having 6 to 42 ring carbon atoms, a monovalent acyl group having 2 to 32 carbon atoms, or a monovalent oxygen-containing hydrocarbon group having 2 to 32 carbon atoms; R.sup.2 is a monovalent hydrocarbon group having 1 to 32 carbon atoms, a monovalent aromatic hydrocarbon group having 6 to 42 ring carbon atoms, a monovalent acyl group having 2 to 32 carbon atoms, a monovalent oxygen-containing hydrocarbon group having 2 to 32 carbon atoms, or a hydrogen atom; R.sup.3 is a divalent hydrocarbon group having 4 carbon atoms; R.sup.4 is a divalent hydrocarbon group having 2 or 3 carbon atoms; m and n are respectively numbers between 1 and 40 and 0 and 20; and m/(m+n)≥0.5.

Alkylene oxide polymerizations are performed in the presence of a double metal cyanide polymerization catalyst and certain magnesium, Group 3-Group 15 metal or lanthanide series metal compounds. The presence of the magnesium, Group 3-Group 15 metal or lanthanide series metal compound provides several benefits including more rapid catalyst activation, faster polymerization rates and the reduction in the amount of ultra high molecular weight polymers that are formed. The catalyst mixture is unexpectedly useful in making polyethers having low equivalent weights.

Alkylene oxide polymerizations are performed in the presence of a double metal cyanide polymerization catalyst and certain magnesium, Group 3-Group 15 metal or lanthanide series metal compounds. The presence of the magnesium, Group 3-Group 15 metal or lanthanide series metal compound provides several benefits including more rapid catalyst activation, faster polymerization rates and the reduction in the amount of ultra high molecular weight polymers that are formed. The catalyst mixture is unexpectedly useful in making polyethers having low equivalent weights.