摘要:
Carboxylic esters obtained by reacting olefinically unsaturated compounds with carbon monoxide and alcohols and containing aldehydes, acetals and/or unsaturated compounds are purified by(a) treating the carboxylic ester which contains an aldehyde, acetal or unsaturated compound in a first stage at from 20.degree. to 200.degree. C. with a strongly acidic agent and(b) hydrogenating the mixture thus treated in a second stage at from 50.degree. to 200.degree. C. under a pressure of from 1 to 50 bar in the presence of one or more metals of subgroup VIII of the periodic table and(c) removing low and high boilers from the hydrogenated mixture obtained in stage b by distillation and obtaining a pure carboxylic ester.
摘要:
A molded iron catalyst material which has an indentation hardness of from 850 to 1500 kp/cm.sup.2 and contains metallic iron particles, obtained from iron oxide particles by contact with hydrogen at less than 500.degree. C., and a lubricant, its preparation and its use.
摘要翻译:一种模压铁催化剂材料,其压痕硬度为850至1500kp / cm 2,并含有通过在低于500℃与氢接触的氧化铁颗粒获得的金属铁颗粒,以及润滑剂及其制备及其用途 。
摘要:
Saturated primary amines are prepared by reacting a nitrile with hydrogen at elevated temperature under superatmospheric pressure in the presence of ammonia and a metallic iron catalyst which has been obtained by reducing anisometric iron oxide particles with hydrogen at not more than 500.degree. C.
摘要:
A filter for aquarium operating in accordance with the lifting-lowering principle comprises a housing with at least one filter compartment for a filter material, a pump which aspirates water after passing through the filter compartment through a suction conduit and supplies the water back into an aquarium, at least one auxiliary chamber supplied with water and a float-controlled valve device controlling an outlet of the auxiliary chamber and communicating with the suction conduit, an auxiliary housing in which the auxiliary chamber is provided and supplied with water filtered after passing of the filter compartment in accordance with the principle of communicating pipes. A passage which is connected with the suction conduit has a valve opening which is alternatingly closeable and openable by a float-controlled valve closing member of the valve device. In another embodiment, a supply is formed as a passage which passes through the filter compartment and is sealed from the latter and opens in a bottom chamber provided in the housing under a lowermost one of the filter compartments, so that the aspiration of the supplied water is performed from below and from the bottom chamber through the filter compartment upwardly with accompanying filtering.
摘要:
5-Membered, 6-membered or 7-membered cyclic imines are prepared by hydrogenating a C.sub.2 -C.sub.4 -alkanedinitrile in the liquid phase, at from 180.degree. to 300.degree. C. and under superatmospheric pressure, in the presence of a catalyst, by a process in which an iron catalyst obtained by reduction of an iron oxide with hydrogen at .ltoreq.500.degree. C. is used.
摘要:
A process for working up mother liquors resulting from the preparation of adipic acid by oxidation of cyclohexanol or cyclohexanone or mixtures thereof with nitric acid entails removal of nitric acid by azeotropic distillation with water, heating the resulting melt at from 130.degree. to 180.degree. C. and then dissolving it in water, treating the aqueous solution with cation exchangers, subsequently again evaporating off the water and heating the resulting dicarboxylic acid melt at from 200.degree. to 240.degree. C. and then obtaining a mixture of dicarboxylic acids by distillation.
摘要:
Molded iron catalysts which contain metallic iron particles, obtained from anisometric iron oxide particles by contact with hydrogen at .ltoreq.500.degree. C., and a lubricant, are prepared.
摘要:
Air vent consisting of a fixed, gridlike apertured front panel and a stop plate disposed behind it, which plate is movable by a control mechanism in the direction of its plane and to the plane of the front panel and which plate in a position resting against the back of the front panel closes the grid apertures, but which in a separated position opens the grid apertures of the front panel for the passage of air.
摘要:
A sidecar steering aid. A coupling mechanism is provided for coupling the sidecar to a steering member of a vehicle to which the sidecar is attached. The coupling mechanism includes a spring adapted to provide resistance to compression and tension about a neutral position of the spring. The neutral position is biased with respect to the turning wheel so that the wheel is “cocked” a predetermined amount by the spring.
摘要:
The covering device for an aquarium, terrarium or like vivarium for living things includes an approximately rectangular frame (13); an upwardly openable cover member (15) pivotally mounted on the frame; a lighting device (17) mounted on the bottom side (16) of the cover member (15); a device for locking and releasing the cover member (15) when it is in a closed position on the frame (13) and a drive mechanism (18) for pivoting the cover member (15) upward automatically automatically to open it when the cover member (15) is released by the locking and releasing device, at least over a predetermined initial pivot angle range. A brake device for braking the action of the drive mechanism can also be provided.