Processes are disclosed for the conversion of 1,6-hexanediol to adipic acid employing a chemocatalytic reaction in which 1,6-hexanediol is reacted with oxygen in the presence of particular heterogeneous catalysts including at least one of platinum or gold. The metals are preferably provided on a support selected from the group of titania, stabilized titania, zirconia, stabilized zirconia, silica or mixtures thereof, most preferably zirconia stabilized with tungsten. The reaction with oxygen is carried out at a temperature from about 100° C. to about 300° C. and at a partial pressure of oxygen from about 50 psig to about 2000 psig.

Processes are disclosed for the conversion of 1,6-hexanediol to adipic acid employing a chemocatalytic reaction in which 1,6-hexanediol is reacted with oxygen in the presence of particular heterogeneous catalysts including at least one of platinum or gold. The metals are preferably provided on a support selected from the group of titania, stabilized titania, zirconia, stabilized zirconia, silica or mixtures thereof, most preferably zirconia stabilized with tungsten. The reaction with oxygen is carried out at a temperature from about 100° C. to about 300° C. and at a partial pressure of oxygen from about 50 psig to about 2000 psig.

Processes are disclosed for the conversion of 1,6-hexanediol to adipic acid employing a chemocatalytic reaction in which 1,6-hexanediol is reacted with oxygen in the presence of particular heterogeneous catalysts including at least one of platinum or gold. The metals are preferably provided on a support selected from the group of titania, stabilized titania, zirconia, stabilized zirconia, silica or mixtures thereof, most preferably zirconia stabilized with tungsten. The reaction with oxygen is carried out at a temperature from about 100° C. to about 300° C. and at a partial pressure of oxygen from about 50 psig to about 2000 psig.

The present invention relates to a high-performance polyoxometalate catalyst and a method of preparing the same. More particularly, the present invention provides a high-performance polyoxometalate catalyst, the activity and selectivity of which may be improved by controlling the content of vanadium and the like and which has superior reproducibility and may unsaturated carboxylic acid from unsaturated aldehyde in a high yield for a long time, a method of preparing the same, and the like.

The present invention relates to a high-performance polyoxometalate catalyst and a method of preparing the same. More particularly, the present invention provides a high-performance polyoxometalate catalyst, the activity and selectivity of which may be improved by controlling the content of vanadium and the like and which has superior reproducibility and may unsaturated carboxylic acid from unsaturated aldehyde in a high yield for a long time, a method of preparing the same, and the like.

The present invention provides a method for allowing a used inert material that has been subjected to a reaction once, which is disposed of in the background art, to be used again as well as a brand-new one. A method of recovering an inert material of the present invention is characterized by in the fixed-bed reactor, the inert material is loaded in an inert material layer provided between a first-stage catalyst layer and a second-stage catalyst layer, the first-stage catalyst layer is loaded with a first-stage catalyst for producing acrolein from propylene, and the second-stage catalyst layer is loaded with a second-stage catalyst for producing acrylic acid from acrolein, the method comprising the steps of: extracting the inert material from the fixed-bed reactor; washing the extracted inert material; and screening the washed inert material.

The present invention provides a method for allowing a used inert material that has been subjected to a reaction once, which is disposed of in the background art, to be used again as well as a brand-new one. A method of recovering an inert material of the present invention is characterized by in the fixed-bed reactor, the inert material is loaded in an inert material layer provided between a first-stage catalyst layer and a second-stage catalyst layer, the first-stage catalyst layer is loaded with a first-stage catalyst for producing acrolein from propylene, and the second-stage catalyst layer is loaded with a second-stage catalyst for producing acrylic acid from acrolein, the method comprising the steps of: extracting the inert material from the fixed-bed reactor; washing the extracted inert material; and screening the washed inert material.

The present invention relates to a process for treating aqueous effluents containing formaldehyde by distillation in the presence of acetic acid, in particular to a process for treating aqueous solutions resulting from the synthesis of acrylic acid. The invention also relates to the use of the purified aqueous solution in a process for producing acrylic acid by catalytic oxidation of propylene and/or propane in steam dilution.

The present invention relates to a process for treating aqueous effluents containing formaldehyde by distillation in the presence of acetic acid, in particular to a process for treating aqueous solutions resulting from the synthesis of acrylic acid. The invention also relates to the use of the purified aqueous solution in a process for producing acrylic acid by catalytic oxidation of propylene and/or propane in steam dilution.

A method for producing a catalyst for unsaturated carboxylic acid synthesis is proposed. The method includes: obtaining a dried product by drying and heat-treating a starting material mixed liquid in which supply source compounds of respective catalyst component elements are integrated; and forming a catalyst precursor by supporting powder to be supported on a carrier in the form of a particle aggregate. The powder to be supported is either the dried product or obtained from the dried product. The method further includes calcining the catalyst precursor to form the catalyst. The mass loss rate of the powder to be supported at 300° C. is less than 5 percent by mass, and the difference between the mass loss rate of the powder at 370° C. and the mass loss rate of the powder at 300° C. is not less than 1 percent by mass and not more than 6 percent by mass.