Abstract: A fuel pump unit comprising a housing part (4) arranged between an electric motor (2) and a fuel pump (3). The housing part is provided with expansion joints for compensating thermal expansions or swelling of the material of the housing part (4). The gap between the impeller (6) and the housing parts (4, 5) of the fuel pump (3) can be kept constant by virture of the expansion joints, whereby the fuel pump (3) is essentially prevented from jamming especially when it runs dry.

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: The invention relates to a supply pump embodied as a side channel pump, whereby several sections (14-16) forming the cross-section of a supply chamber (13) each comprise radii. The origins of the external radii are arranged on the front face of a pump housing facing the one rotor. The sections (14-16) comprise common tangents in the adjacent regions thereof. A particularly high efficiency for the supply pump can thus be guaranteed.

Abstract: In a fuel pump (6) designed as a side channel pump, in each case two conveying chambers (20-23) one surrounding the other concentrically are arranged on two impellers (9, 10). The conveying chambers (20, 21) of one impeller (9) are connected to an inlet duct (25), while the conveying chambers (22, 23) of the other impeller (10) are connected to an outlet duct (26). A connection (24) of the conveying chambers (20-23) is arranged in a partition (17) keeping the impellers (9, 10) at a distance from one another. As a result, the fuel pump (6) has an especially high volume flow, along with a very high conveying pressure.

Abstract: The invention relates to a process for the production of hydrogen peroxide by the anthraquinone process, comprising a hydrogenation stage, an oxidation stage and an extraction stage. According to the invention, catalytic hydrogenation of anthraquinone derivatives dissolved in a working solution is carried out in the presence of added molecular oxygen. Per mol hydrogen, 0.1 to 10 mmol oxygen is preferably introduced into the hydrogenation stage with the hydrogenating gas, in mixture with an inert gas and/or dissolved and/or dispersed in the working solution. This increases the residence time of the catalyst.

Abstract: A fuel pump unit comprising a housing part (4) arranged between an electric motor (2) and a fuel pump (3). The housing part is provided with expansion joints for compensating thermal expansions or swelling of the material of the housing part (4). The gap between the impeller (6) and the housing parts (4, 5) of the fuel pump (3) can be kept constant by virture of the expansion joints, whereby the fuel pump (3) is essentially prevented from jamming especially when it runs dry.

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: In a feed pump (2), guide vanes (9) fastened on a driven impeller (7) project into a recess (11) of a molding (8) annularly surrounding the impeller (7). The guide vanes (9) are located with a slight clearance opposite the wall of the recess (11). The guide vanes (9) can thereby have a particularly large surface. Moreover, a depositing of dirt in the radially outer region of the impeller (7) is avoided.

Abstract: An impeller for a delivery pump in which profiled section (14) comprising webs (15) is located on the outer periphery of an impeller (4) for a feed pump (2) that is configured as a side channel pump. The webs (15) are arranged at an ascending incline, viewed in the rotational direction of the impeller (4) from the designated pressure side to the designated intake side. This permits flow losses between the radial external region of the impeller (4) and the housing parts (6, 7) of the feed pump (2) to be maintained at a particularly low level.

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: 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: 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: 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: In a fuel pump (6) designed as a side channel pump, in each case two conveying chambers (20-23) one surrounding the other concentrically are arranged on two impellers (9, 10). The conveying chambers (20, 21) of one impeller (9) are connected to an inlet duct (25), while the conveying chambers (22, 23) of the other impeller (10) are connected to an outlet duct (26). A connection (24) of the conveying chambers (20-23) is arranged in a partition (17) keeping the impellers (9, 10) at a distance from one another. As a result, the fuel pump (6) has an especially high volume flow, along with a very high conveying pressure.

Abstract: The invention relates to a process for the production of hydrogen peroxide by the anthraquinone process, comprising a hydrogenation stage, an oxidation stage and an extraction stage. According to the invention, catalytic hydrogenation of anthraquinone derivatives dissolved in a working solution is carried out in the presence of added molecular oxygen. Per mol hydrogen, 0.1 to 10 mmol oxygen is preferably introduced into the hydrogenation stage with the hydrogenating gas, in mixture with an inert gas and/or dissolved and/or dispersed in the working solution. This increases the residence time of the catalyst.

Abstract: The invention relates to a side-channel pump for transporting fuel in a motor vehicle. Said pump comprises a partial annular channel (11) located in housing sections (4, 5), said channel having a greater radius than a crown of vane chambers (10) that are located in the impeller (6). The vane chambers (10) and the partial annular channel (11) respectively have the same width. This prevents wear and tear to the sealing surfaces.

Abstract: An impeller for a delivery pump in which profiled section (14) comprising webs (15) is located on the outer periphery of an impeller (4) for a feed pump (2) that is configured as a side channel pump. The webs (15) are arranged at an ascending incline, viewed in the rotational direction of the impeller (4) from the designated pressure side to the designated intake side. This permits flow losses between the radial external region of the impeller (4) and the housing parts (6, 7) of the feed pump (2) to be maintained at a particularly low level.

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: The invention relates to a supply pump embodied as a side channel pump, whereby several sections (14-16) forming the cross-section supply of a supply chamber (13) each comprise radii. The origins of the external radii are arranged on the front face of a pump housing facing the one rotor. The sections (14-16) comprise common tangents in the adjacent regions thereof. A particularly high efficiency for the supply pump can thus be guaranteed.

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.