Abstract: The invention relates to a method for synthesis of aliphatic isocyanates from aromatic isocyanates in substantially 3 stages. In particular, the invention relates to a method for synthesis of bis{4-isocyanatocyclohexyl}methane (H12MDI) from bis{4-isocyanatophenyl}methane (MDI). More especially, the invention relates to a method for synthesis of H12MDI with a trans-trans isomer content of <30%, preferably of <20%, particularly preferably of 5 to 15%.

Abstract: The invention relates to a process for increasing the selectivity of the hydrogenation of 4,4?-diaminodiphenylmethane (4,4?-MDA) to diaminodicyclohexylmethane (4,4?-HMDA) by catalytic hydrogenation of a mixture containing 4,4?-MDA as the main component and its mono-N-methyl derivative as a secondary component. According to the invention, the hydrogenation is terminated before a conversion of 4,4?-MDA to 4,4?-HMDA of 99% is achieved. Under these conditions, a substantially smaller proportion of the N-methyl-4,4?-MDA is hydrogenated to N-methyl-4,4-HMDA.

Abstract: What is claimed is a dealuminated catalyst carrier, a process for producing a catalyst carrier with reduced aluminium content based on naturally occurring lattice-layer silicates, such as, for example, montmorillonite, as well as a process for the hydration reaction of C2- or C3-olefins in which said catalyst carrier with reduced aluminium content is used. For acid-catalysed hydration reaction the catalyst carrier is impregnated with phosphoric acid. The improvements according to the invention of the hydration reaction compared to conventional processes include the fact that no aluminium is leached out of the carrier in the presence of the phosphoric acid. As a result no more blockage of the succeeding apparatus due to aluminum phosphate is expected.

Abstract: A catalyst support comprising silicates is described. This catalyst support has a lower aluminum content than naturally occurring sheet silicates and can be used in the hydration of C2 and C3 olefins to produce C2 and C3 alcohols. A method for the production of the catalyst support and a process for hydrating C2 and C3 olefins are also described. One advantage of this catalyst support is the reduction in aluminum leaching that occurs when this catalyst is used in the presence of phosphoric acid.

Abstract: What is claimed is a dealuminated catalyst carrier, a process for producing a catalyst carrier with reduced aluminum content based on naturally occurring lattice-layer silicates, such as, for example, montmorillonite, as well as a process for the hydration reaction of C2- or C3-olefins in which said catalyst carrier with reduced aluminium content is used. For acid-catalysed hydration reaction the catalyst carrier is impregnated with phosphoric acid. The improvements according to the invention of the hydration reaction compared to conventional processes include the fact that no aluminium is leached out of the carrier in the presence of the phosphoric acid. As a result no more blockage of the succeeding apparatus due to aluminium phosphate is expected.

Abstract: A process for the continuous epoxidation of propene with hydrogen peroxide in the presence of a titanium silicalite catalyst and a methanol solvent, wherein the catalyst is periodically regenerated by washing with a methanol solvent at a temperature of at least 100° C. and the epoxidation reaction is carried out for periods of more than 300 h between two regeneration steps.

Abstract: A continuous process for the epoxidation of olefins with hydrogen peroxide in the presence of a heterogeneous catalyst promoting the epoxidation reaction, whereby the aqueous reaction mixture contains i) an olefin; ii) hydrogen peroxide; iii) less than 100 wppm of alkali metals, earth alkali metals, both irrespective whether in ionic, complex or covalently bonded form, bases or cations of bases having a pkB of less than 4.5, or combinations thereof; and, iv) at least 100 wppm of bases or cations of bases having a pkB of at least 4.5 or combinations thereof, whereby the wppm are based on the total weight of hydrogen peroxide in the reaction mixture.

Abstract: A process for the continuous epoxidation of propene with hydrogen peroxide in the presence of a titanium silicalite catalyst and a methanol solvent, wherein the catalyst is periodically regenerated by washing with a methanol solvent at a temperature of at least 100° C. and the epoxidation reaction is carried out for periods of more than 300 h between two regeneration steps.

Abstract: Aqueous-organic or organic hydrogen peroxide solutions can be produced by direct synthesis in the presence of a catalyst fixed bed and an organic solvent. According to the invention, a non-explosive gas mixture comprising H2 and O2 is employed and a liquid reaction medium comprising organic solvent and bromide and/or iodide is passed over the fixed bed with a cross-section loading of at least 0.3 m/h. In the case of a trickle bed procedure with a cross-section loading of 0.3 m/h to 2 m/h, 4 to 10 wt. % methanolic H2O2 solutions can be prepared with a high productivity.

Abstract: The invention relates to a method for hydrogenation of aromatic urethanes, which contain one or more aromatic rings and one or more urethane groups bonded directly and/or indirectly to one aromatic ring or to different aromatic rings, using hydrogen in the presence of a supported catalyst, which contains ruthenium as active metal. The catalyst support of the catalyst to be used according to the invention has a BET surface ranging from larger than 30 m2/g to smaller than 70 m2/g and more than 50% of the pore volume of the catalyst support is represented by macropores with a pore diameter of larger than 50 nm and less than 50% is represented by mesopores with a pore diameter of 2 to 50 nm. The method is suitable in particular for hydrogenation of dibutyl 4,4′-methylenedicarbanilate to dibutyl 4,4′-methylenedicyclohexylcarbamate with a trans-trans isomer content of <30%, preferably of <20%, particularly preferably of 5 to 15%.

Abstract: Aqueous-organic or organic hydrogen peroxide solutions can be produced by direct synthesis in the presence of a catalyst fixed bed and an organic solvent. According to the invention, a non-explosive gas mixture comprising H2 and O2 is employed and a liquid reaction medium comprising organic solvent and bromide and/or iodide is passed over the fixed bed with a cross-section loading of at least 0.3 m/h. In the case of a trickle bed procedure with a cross-section loading of 0.3 m/h to 2 m/h, 4 to 10 wt. % methanolic H2O2 solutions can be prepared with a high productivity.

Abstract: A continuous process for the epoxidation of olefins with hydrogen peroxide in the presence of a heterogeneous catalyst promoting the epoxidation reaction, whereby the aqueous reaction mixture contains i) an olefin; ii) hydrogen peroxide; iii) less than 100 wppm of alkali metals, earth alkali metals, both irrespective whether in ionic, complex or covalently bonded form, bases or cations of bases having a pkB of less than 4.5, or combinations thereof; and, iv) at least 100 wppm of bases or cations of bases having a pkB of at least 4.5 or combinations thereof, whereby the wppm are based on the total weight of hydrogen peroxide in the reaction mixture.

Abstract: A process for the catalytic epoxidation of olefins in the presence of a titanium containing zeolite catalyst and a polar solvent whereby the deactivation of the catalyst upon recycling of the solvent has been considerably reduced. In the process one or more nitrogen containing compounds are introduced at some stage, a solvent stream is recovered, treated to contain less than 50 wppm nitrogen in the form of organic nitrogen compounds and at least a part of it is recycled to the epoxidation step. Also disclosed is a process for the catalytic epoxidation of propene which integrates the treatment and recycle of the solvent into the workup of the reaction mixture.

Abstract: An aqueous hydrogen peroxide solution containing i) less than 50 wppm alkali metals, alkaline earth metals or combinations thereof in total, irrespective whether the alkali or alkaline earth metals are present in cationic or complex form; ii) less than 50 wppm of amines having a pkB of less than 4.5 or the corresponding protonated compounds in total; and iii) at least 100 wppm anions or compounds that can dissociate to form anions in total, where the wppm are based on the weight of hydrogen peroxide and the concentration of hydrogen peroxide is more than 50% by weight based on the total weight of the hydrogen peroxide solution. A process for preparation of said hydrogen peroxide solution and the use of said solution in a process for epoxidation of olefins is also disclosed.

Abstract: The invention relates to a method for hydrogenation of aromatic urethanes, which contain one or more aromatic rings and one or more urethane groups bonded directly and/or indirectly to one aromatic ring or to different aromatic rings, using hydrogen in the presence of a supported catalyst, which contains ruthenium as active metal. The catalyst support of the catalyst to be used according to the invention has a BET surface ranging from larger than 30 m2/g to smaller than 70 m2/g and more than 50% of the pore volume of the catalyst support is represented by macropores with a pore diameter of larger than 50 nm and less than 50% is represented by mesopores with a pore diameter of 2 to 50 nm.

Abstract: The invention relates to a method for synthesis of aliphatic isocyanates from aromatic isocyanates in substantially 3 stages. In particular, the invention relates to a method for synthesis of bis{4-isocyanatocyclohexyl}methane (H12MDI) from bis{4-isocyanatophenyl}methane (MDI). More especially, the invention relates to a method for synthesis of H12MDI with a trans-trans isomer content of <30%, preferably of <20%, particularly preferably of 5 to 15%.

Abstract: The invention relates to a process for hydrogenating an aromatic amine that has at least one amino group bound to an aromatic nucleus with hydrogen in the presence of a supported catalyst that contains at least ruthenium as active metal. The catalyst support has a BET surface area in the range from greater than 30 m2/g to less than 70 m2/g and more than 50% of the pore volume of the catalyst support is formed by macropores having a pore diameter of greater than 50 nm and less than 50% are mesopores having a pore diameter of 2 to 50 nm.

Abstract: A dealuminized catalyst carrier, a method for producing a catalyst carrier having a lower aluminum content on the basis of naturally occurring sheet silicates, such as montmorilonite, and to a method for hydrating C2 or C3 olefins which uses the catalyst carrier having a lower aluminum content. For the acid-catalyzed hydration reaction the carrier is saturated with phosphoric acid. The improvement the invention provides for in comparison with known hydration methods is characterized in that the carrier is no longer subject to aluminum leaching in the presence of phosphoric acid. As a result, there is no further risk of aluminum phosphate blockages occurring in the apparatus positioned downstream of the reaction.

Abstract: The invention relates to a high performance catalyst containing a layer on an inert carrier body comprising noble metals from the platinum group deposited on support materials. The catalyst is characterised in that, the layer comprises platinum deposited in a washcoat consisting of Al2O3 which is stabilized with lanthana (La2O3), ceria (CeO2), which is stabilized with zirconia (ZrO2) and praseodymium (Pr6O11). The supprot is promoted by sulfur-containing compounds which come from at least one of following compounds: platinum sulfite (PtSO3), sulfuric acid (H2SO4), ammonium sulfate ((NH4)2SO4), titanium oxysulfate (TiOSO4), titanium sulfate (Ti2(SO4)3), and zirconium sulfate (Zr(SO4)2).

Abstract: A process for the epoxidation of olefins which includes