Provided is a method for preparing a diol. In the method, a saccharide and hydrogen as raw materials are contacted with a catalyst in water to prepare the diol. The employed catalyst is a composite catalyst comprised of a main catalyst and a cocatalyst, wherein the main catalyst is a water-insoluble acid-resistant alloy; and the cocatalyst is a soluble tungstate and/or soluble tungsten compound. The method uses an acid-resistant, inexpensive and stable alloy needless of a support as a main catalyst, and can guarantee a high yield of the diol in the case where the production cost is relatively low.

Provided is a method for preparing a diol. In the method, a saccharide and hydrogen as raw materials are contacted with a catalyst in water to prepare the diol. The employed catalyst is a composite catalyst comprised of a main catalyst and a cocatalyst, wherein the main catalyst is a water-insoluble acid-resistant alloy; and the cocatalyst is a soluble tungstate and/or soluble tungsten compound. The method uses an acid-resistant, inexpensive and stable alloy needless of a support as a main catalyst, and can guarantee a high yield of the diol in the case where the production cost is relatively low.

A process for preparing C.sub.4 to C.sub.10 monohydroxy compounds from a bottom fraction arising in the distillation of a crude mixture of C.sub.4 to C.sub.10 oxo-process aldehydes from cobalt-catalyzed or rhodium-catalyzed hydroformylation, or in the distillation of a crude mixture of C.sub.4 to C.sub.10 oxo-process alcohols, which comprises contacting the bottom fraction in the presence of hydrogen with a catalyst comprising copper oxide and aluminum oxide, at a temperature of 150 C. to 300 C. and a pressure of 20 bar to 300 bar and subjecting the resulting crude hydrogenation product to distillation, and the amount of C.sub.4 to C.sub.10 monohydroxy compounds present in the crude hydrogenation product after the hydrogenation being greater than the amount of C.sub.4 to C.sub.10 monohydroxy compounds given stoichiometrically from the hydrogenation of the ester and aldehyde compounds present in the bottom fraction, including the C.sub.4 to C.sub.10 monohydroxy compounds still present in the bottom fraction before the hydrogenation.

A process for preparing C.sub.4 to C.sub.10 monohydroxy compounds from a bottom fraction arising in the distillation of a crude mixture of C.sub.4 to C.sub.10 oxo-process aldehydes from cobalt-catalyzed or rhodium-catalyzed hydroformylation, or in the distillation of a crude mixture of C.sub.4 to C.sub.10 oxo-process alcohols, which comprises contacting the bottom fraction in the presence of hydrogen with a catalyst comprising copper oxide and aluminum oxide, at a temperature of 150 C. to 300 C. and a pressure of 20 bar to 300 bar and subjecting the resulting crude hydrogenation product to distillation, and the amount of C.sub.4 to C.sub.10 monohydroxy compounds present in the crude hydrogenation product after the hydrogenation being greater than the amount of C.sub.4 to C.sub.10 monohydroxy compounds given stoichiometrically from the hydrogenation of the ester and aldehyde compounds present in the bottom fraction, including the C.sub.4 to C.sub.10 monohydroxy compounds still present in the bottom fraction before the hydrogenation.

This invention relates to a method for the conversion of lignocellulosic biomass into ethyl esters of carboxylic acids. Said method consists of treating the biomass material with an oxidizing agent that is incorporated in an solution comprising one or more acids, one or more alcohols and water, and subsequently performing a catalytic reaction at a higher temperature using the same acidic solution into which a larger volume of alcohol is added, in such a way that the catalytic conversion occurs in a medium with a much higher concentration of alcohol, i.e. with a much higher alcohol-to-water wt ratio. Such a method results in relatively high yields of ethyl esters, such as ethyl esters of formic, acetic, and levulinic acids, while producing a low yield of dialkyl ethers, which are unwanted by-products. The concentration of the oxidizing agent in the pre-treatment step is preferably higher than 6.0 wt %. The oxidizing agent is preferably a Fenton or Fenton-type reagent, and most preferably hydrogen peroxide activated by Fe (II), and/or Ti (IV) ions. The alcohol is preferably ethanol, and when ethanol is used, diethyl ether is formed as the unwanted dialkyl ether by-product. Preferably, the biomass material is pelleted before treatment.

This invention relates to a method for the conversion of lignocellulosic biomass into ethyl esters of carboxylic acids. Said method consists of treating the biomass material with an oxidizing agent that is incorporated in an solution comprising one or more acids, one or more alcohols and water, and subsequently performing a catalytic reaction at a higher temperature using the same acidic solution into which a larger volume of alcohol is added, in such a way that the catalytic conversion occurs in a medium with a much higher concentration of alcohol, i.e. with a much higher alcohol-to-water wt ratio. Such a method results in relatively high yields of ethyl esters, such as ethyl esters of formic, acetic, and levulinic acids, while producing a low yield of dialkyl ethers, which are unwanted by-products. The concentration of the oxidizing agent in the pre-treatment step is preferably higher than 6.0 wt %. The oxidizing agent is preferably a Fenton or Fenton-type reagent, and most preferably hydrogen peroxide activated by Fe (II), and/or Ti (IV) ions. The alcohol is preferably ethanol, and when ethanol is used, diethyl ether is formed as the unwanted dialkyl ether by-product. Preferably, the biomass material is pelleted before treatment.

Disclosed is a novel transition metal complex containing N-heterocyclic carbene and a sulfonamide group, or N-heterocyclic carbene and an amide group, and application thereof, the traquesnsition metal complex having a wider range of general purposes in olefin metathesis and being able to be variably controlled in reactivity.

Disclosed is a novel transition metal complex containing N-heterocyclic carbene and a sulfonamide group, or N-heterocyclic carbene and an amide group, and application thereof, the traquesnsition metal complex having a wider range of general purposes in olefin metathesis and being able to be variably controlled in reactivity.

Disclosed is a novel transition metal complex containing N-heterocyclic carbene and a sulfonamide group, or N-heterocyclic carbene and an amide group, and application thereof, the traquesnsition metal complex having a wider range of general purposes in olefin metathesis and being able to be variably controlled in reactivity.

The invention relates to a process for the preparation of a deuterated ethanol from ethanol, D.sub.2O, a ruthenium catalyst, and a co-solvent.