Abstract:
The invention relates to a process for preparing methylenediphenyl diisocyanates which comprises at least the steps: A) reaction of aniline with formaldehyde in the presence of hydrochloric acid as catalyst to give a mixture of diamines and polyamines of the diphenylmethane series (MDA) and subsequent at least partial neutralization of the hydrochloric acid by means of alkali metal hydroxide, B) reaction of the mixture of diamines and polyamines of the diphenylmethane series obtained in step A) with phosgene to give a mixture of diisocyanates and polyisocyanates of the diphenylmethane series (MDI) and hydrogen chloride, wherein C) the hydrochloric acid which has been neutralized in step A) is separated off in the form of a solution containing alkali metal chloride and is subsequently at least partly fed to an electrochemical oxidation to form chlorine, alkali metal hydroxide and optionally hydrogen and D) at least part of the chlorine produced in step C) is used for preparing the phosgene used in step B).
Abstract:
The present invention relates to a gas diffusion electrode that includes an electrically conductive carrier, and a porous coating based on an electrochemically active catalyst and a hydrophobic material, wherein the electrode has a first side facing an oxygen-containing gas and a second side facing an alkaline electrolyte, wherein the catalyst comprises a noble metal as a catalytically active component, wherein the hydrophobic material comprises a hydrophobic polymer, and wherein the coating comprising the catalyst has a pore volume from 10 to 500 mm3/g, and a pore diameter in the range from 100 to 10,000 nm.
Abstract:
The present invention relates to an electrode that includes an electrically conducting substrate based on a valve metal having a main proportion of titanium, tantalum or niobium, and an electrocatalytically active coating comprising up to 50 mol % of a noble metal oxide or noble metal oxide mixture and at least 50 mol % of titanium oxide. The coating includes a minimum proportion of oxides of anatase structure determined by a ratio of the signal height of the most intensive anatase reflection in an x-ray diffractogram (CuKα radiation) after subtraction of a linear background to the signal height of the most intensive rutile reflection in the same diffractogram, wherein the ratio is at least 0.6.
Abstract:
An electronic plug-in module for accommodation in a module rack with a mounting rail, wherein the plug-in module includes a circuit board, a front plate and a mounting device, the mounting device comprises a bearing part, a tensioning part and a fixation element, the bearing part is fixed on front plate, and the tensioning part is connected frictionally to the fixation element and the bearing part in such a manner that a force, by means of which the plug-in module is held with its front plate in a defined position relative to the module rack, is exerted onto the plug-in module transversely to the insertion direction of the plug-in module.
Abstract:
The present invention describes an electrochemical cell, comprising at least an anode half-cell with an anode, a cathode half-cell with a cathode, and an ion exchange membrane arranged between the anode half-cell and the cathode half-cell, the anode and/or the cathode is a gas diffusion electrode. And a gap is provided between the gas diffusion electrode and the ion exchange membrane, and the half-cell with the gas diffusion electrode has an electrolyte feed and an electrolyte discharge as well as a gas inlet and a gas outlet. The electrochemical cell preferably has an electrolyte feed that is hermetically connected to the gap.
Abstract:
The invention relates to a combined process for the preparation of polycarbonate by the phase boundary process and downstream electrolysis of sodium chloride-containing process wastewater.
Abstract:
A process is described for the production of graphite electrodes coated predominantly with noble metal for electrolytic processes, especially for the electrolysis of hydrochloric acid, wherein the surface of a graphite electrode is coated with an aqueous solution of a noble metal compound and then tempered at 150 to 650° C. in the presence of reducing and/or extensively oxygen-free gases.
Abstract:
The invention relates to a method and to a system for producing a filled consumable product, in particular a shell-like consumable product consisting of at least two different substances which form the covering and/or shell of the consumable product and the second filling the consumable product. Said method comprises the following steps: a) a covering, which comprises an opening, is produced; b) a filling is added to the covering via an opening; and c) a cover is applied to the opening in order to close the filled covering. The filling is added according to step b) and the cover is applied according to step c) which takes place simultaneously in one step. Means for adding the filling and means for applying the cover can be displaced together and at a constant distance according to the inventive system.
Abstract:
Processes comprising: (a) reacting phosgene and a monohydroxyl aryl compound in the presence of a suitable catalyst to form a diaryl carbonate and a solution comprising an alkali chloride; (b) separating the diaryl carbonate from the solution; (c) adjusting the pH of the solution to a value of less than or equal to 8 to form a pH-adjusted solution; (d) treating the pH-adjusted solution with an adsorbent to form a treated solution; (e) subjecting at least a portion of the treated solution to electrochemical oxidation to form chlorine and an alkali hydroxide solution; and (f) recycling at least a portion of one or both of the chlorine and the alkali hydroxide solution.
Abstract:
A shelf for electronic plug-in units is provided. The shelf includes at least one support plate that has at least one shaped opening. At least one guide rail is arranged for being mounted on the support plate, which includes a guide groove for receiving the electronic plug-in unit. There is also provided at least one positioning unit arranged on the guide rail, which includes a trunnion insertable form-fittingly into the shaped opening in the support plate to fix a position of the positioning unit relative to the support plate, and a locking element to lock in place an electronic plug-in unit fully inserted into the guide rail.