A purified cyclohexanol of the present invention has a methylcyclopentanol concentration of 10 to 1000 ppm by weight and a cyclohexylcyclohexene isomer concentration of 15 to 500 ppm by weight. A method for producing cyclohexanol of the present invention comprises: Step 1 of producing a solution (I) containing cyclohexanol, methylcyclopentanol, and water by a hydration reaction of cyclohexene; Step 2 of separating the solution (I) into a water phase and an oil phase; Step 3 of obtaining a partially purified cyclohexanol containing methylcyclopentanol from the oil phase; and Step 4 of separating and removing methylcyclopentanol in the partially purified cyclohexanol so as to obtain a purified cyclohexanol having a methylcyclopentanol concentration of 10 to 1000 ppm by weight and a cyclohexylcyclohexene isomer concentration of 15 to 500 ppm by weight.

A purified cyclohexanol of the present invention has a methylcyclopentanol concentration of 10 to 1000 ppm by weight and a cyclohexylcyclohexene isomer concentration of 15 to 500 ppm by weight. A method for producing cyclohexanol of the present invention comprises: Step 1 of producing a solution (I) containing cyclohexanol, methylcyclopentanol, and water by a hydration reaction of cyclohexene; Step 2 of separating the solution (I) into a water phase and an oil phase; Step 3 of obtaining a partially purified cyclohexanol containing methylcyclopentanol from the oil phase; and Step 4 of separating and removing methylcyclopentanol in the partially purified cyclohexanol so as to obtain a purified cyclohexanol having a methylcyclopentanol concentration of 10 to 1000 ppm by weight and a cyclohexylcyclohexene isomer concentration of 15 to 500 ppm by weight.

The present invention relates to a process for preparing phthalic anhydride by gas phase oxidation of aromatic hydrocarbons, in which a gas stream comprising at least one aromatic hydrocarbon and molecular oxygen is passed continuously over a thermostatted catalyst and the supply of the at least one aromatic hydrocarbon to the catalyst is temporarily interrupted after putting the catalyst on stream.

The present invention relates to a process for preparing phthalic anhydride by gas phase oxidation of aromatic hydrocarbons, in which a gas stream comprising at least one aromatic hydrocarbon and molecular oxygen is passed continuously over a thermostatted catalyst and the supply of the at least one aromatic hydrocarbon to the catalyst is temporarily interrupted after putting the catalyst on stream.

Methods of depolymerizing lignin and products obtained therefrom. The methods include reacting lignin in a liquid solvent comprising an oxidation catalyst with the solvent being in contact with 02 gas. The solvent can include aprotic polar solvents. The oxidation catalyst can include heterogeneous catalysts. The methods can be used in the oxidative catalytic fractionation of raw biomass to generate soluble aromatic monomers and a solid carbohydrate residue. Depolymerized lignin products include phenolic and benzoquinone monomers, such as p-hydroxybenzoic acid, vanillin, syringaldehyde, vanillic acid, and/or syringic acid.

Methods of depolymerizing lignin and products obtained therefrom. The methods include reacting lignin in a liquid solvent comprising an oxidation catalyst with the solvent being in contact with 02 gas. The solvent can include aprotic polar solvents. The oxidation catalyst can include heterogeneous catalysts. The methods can be used in the oxidative catalytic fractionation of raw biomass to generate soluble aromatic monomers and a solid carbohydrate residue. Depolymerized lignin products include phenolic and benzoquinone monomers, such as p-hydroxybenzoic acid, vanillin, syringaldehyde, vanillic acid, and/or syringic acid.

The present disclosure discloses an immobilized metalloporphyrin catalyst and its utilization in maleic acid preparation, belonging to the technical field of metalloporphyrin catalytic application. The immobilized metalloporphyrin catalyst is used for catalyzing furfural to prepare maleic acid and is good in catalytic effect, mild in reaction conditions and capable of greatly reducing the energy consumption required in the prior art. The catalyst disclosed by the present disclosure can provide a good microenvironment for a reaction, so that the yield and selectivity of maleic acid are increased; and according to a method disclosed by the present disclosure, the conversion ratio of furfural is 20.4%-95.6%, the yield of maleic acid is 10%-56.1%, and the selectivity is 43.6%-76.1%. Meanwhile, the catalyst is easy to separate and environmentally friendly and may be recycled for many times.

The present disclosure discloses an immobilized metalloporphyrin catalyst and its utilization in maleic acid preparation, belonging to the technical field of metalloporphyrin catalytic application. The immobilized metalloporphyrin catalyst is used for catalyzing furfural to prepare maleic acid and is good in catalytic effect, mild in reaction conditions and capable of greatly reducing the energy consumption required in the prior art. The catalyst disclosed by the present disclosure can provide a good microenvironment for a reaction, so that the yield and selectivity of maleic acid are increased; and according to a method disclosed by the present disclosure, the conversion ratio of furfural is 20.4%-95.6%, the yield of maleic acid is 10%-56.1%, and the selectivity is 43.6%-76.1%. Meanwhile, the catalyst is easy to separate and environmentally friendly and may be recycled for many times.

A catalyst for catalytic oxidation of furfural to prepare maleic acid, relating to the technical field of renewable energy. The catalyst is a mixture of a bromide and a base. A method for preparing the catalyst in catalytic oxidation of furfural to prepare maleic acid. The method includes: mixing the furfural, the bromide-base, an oxidant and a solvent to carry out a reaction to obtain the maleic acid. The present invention has the advantages that the method has a relatively high conversion rate of furfural and a relatively high yield of maleic acid, the conversion rate of furfural is up to 99%, the yield of maleic acid is up to 68.04%; and the catalyst has a high catalytic selectivity and reusability.

The present invention disclosed a single step process for the conversion of cyclohexane to adipic acid by using manganese oxide, tungsten oxide or Mn—WOx nano structure having improved yield and selectivity.