Abstract: Disclosed is a high temperature magnetic stirrer including a permanent magnet positioned underneath a frame supported platform. The magnet is positioned to be rotatable in a plane parallel to the platform. A spiral shaped heating element mounted to the frame is positioned above the platform and centered above the rotatable magnet. The spiral has a diameter sufficient to enclose a portion of a crucible. Means are provided to supply the heating element with electricity, and additional means are secured to the frame to rotate the magnet.

Abstract: A liquid developed electrophotocopier wherein liquid carrier dispersant transferred to a copy sheet concomitantly with the developed image is catalytically oxidized to provide harmless gaseous oxidation products at temperatures sufficiently elevated to vaporize transferred carrier and to dry and fix the transferred image. The catalytic fixer-dryer is brought rapidly to operating temperature by injecting an atomized spray of carrier liquid. The carrier liquid has a low auto-oxidation temperature; and the fixer-dryer is operated above such temperature to ensure complete oxidation of carrier vapors even though the catalyst may have been largely rendered inactive.

Abstract: An apparatus for chlorination of molten magnesium chloride salts, comprising a shell lined with a refractory material and having the interior thereof formed by walls, a bottom and a cover. The lower portion of the shell walls is provided with chlorine inlet means whereas the upper portion has a melt feed inlet means and a chlorinated melt outlet means. The interior of the shell is so tapered downward that its clear opening, F.sub.1, at the level of the chlorine inlet means is not over 0.3 times the clear opening, F.sub.2, at the level of the melt feed inlet means and the chlorinated melt outlet means.

Abstract: An apparatus (21) and method is disclosed for keeping interior walls (28) of a reaction vessel (22) free of undesirable deposits of solid materials in gas-to-solid reactions. The apparatus (21) includes a movable cleaning head (36) which is configured to be substantially complementary to the interior contour of the walls (28) of the reaction vessel (22) and which is disposed in close proximity to the walls (28). The head (36) ejects a stream of gas with a relatively high velocity into a narrow space between the head (36) and the walls (28), and in accordance with Bernoulli's principle the head (36) is biased towards the walls (28) by the pressure prevailing in the reaction vessel (22). The gas ejected from the head (36) is of such composition that it does not participate significantly in the chemical reaction conducted in the reaction vessel (22).

Abstract: An apparatus for the storage and production of hydrogen from a solid compound.The solid compound is a compound of at least one rare earth and a metal of group VIII of the periodic system, which can selectively fix hydrogen by hydrogenation. It is placed within a sealed container and is in a compact and machinable or workable form.

Abstract: A system for providing homogenized fluids of fuel and water utilizes a chamber (70) in which the fuel and water is loaded in predetermined quantities. The chamber contains heater (75) which is electrically activated to convert the liquid fuel and water to their vapor states. The chamber also contains a transducer (74) which vibrates the liquified composition of the fuel and water vapors at high frequency rates so as to additionally homogenize it prior to being transferred to storage vessel (96). A vaporizer (99') may be connected to the storage vessel so as to be fed by the homogenized liquid when this system is used in conjunction with an internal combustion engine. The system may provide mechanism (77, 79) for evacuating chamber (70) prior to loading the fuel and water into such chamber.

Abstract: A process and system of operation for combusting nitrogen-containing fuels with resulting low NO.sub.x emissions. A fuel-rich mixture of the fuel is combusted in a catalytic bed which is carried by a support structure. Active or passive means are provided for limiting transfer of heat from the bed into the support structure for minimizing formation of NO.sub.x during combustion. The active means for limiting the heat transfer includes, in different embodiments, electrical resistance back heating, induction back heating, exhaust gas back heating, and combustion fired back heating. The passive means for limiting the heat transfer includes, in different embodiments, a body of heat insulating material between the bed and support structure, or the insulating effect of the outer cells of the bed within a recess in the support structure.

Abstract: An electrically heated reactor for high temperature and pressure chemical reactions includes a reactor vessel having an inlet opening for introduction of raw material onto the reactor and an outlet opening for removal of heated material from the reactor. An electric heating assembly extends through the inlet opening into the interior of the vessel and includes a metallic inner tube through which raw material can be introduced into the vessel and an outer ferromagnetic tube arranged in spaced concentric relationship with respect to the inner tube and generally coextensive in length therewith. The innermost ends of the tubes are electrically connected to each other by a metallic member which seals the space between the tubes. An electrical insulating medium is disposed within the space.

Abstract: A hydrogen generator decomposes water into hydrogen and oxygen, and includes an induction coil which is electrically heated to a temperature sufficient to decompose water passing therethrough. A generator coil is connected in communicating relation to the induction coil, and is positioned in a fire resistant crucible containing ferrous oxide pellets. Oxygen and hydrogen produced by decomposition of water pass through the ferrous oxide pellets where the oxygen reacts with the ferrous oxide and the hydrogen is burned to produce heat for heating a building, such as a conventional home.

Abstract: A furnace for heating particulate material comprises an air-tight shell and a heat insulating lining which define a hollow shaft. Electrical resistance heating elements spaced along the length of the hollow shaft adjacent the insulating lining. A baffle system supported within the shaft promotes heating by radiation and convection. The baffle system has side supports vertically positioned within the shaft, a plurality of inner trays each defining pairs of sloping surfaces joined at a ridge, and a plurality of outer trays each defining a sloping surface. The outer trays are arranged to receive material falling from an inner tray thereabove and to deliver material to the ridge of an inner tray therebelow.

Abstract: The disclosed invention pertains to an autoclave apparatus for receiving parts to be bonded or cured which includes a removable cover on the end of a pressure vessel having radiant heat means that directs heat directly onto the surface of a product to effect a bonding or curing temperature without substantially heating the pressure vessel and its parts.

Abstract: A system for denitrating a starting nitric acid solution by irradiation of microwaves to obtain oxide product of the solution comprises a receiver for receiving the solution, a rectangular oven vessel provided with a bottom plate on which the receiver is put, and a conveying mechanism located below the bottom plate for continuously conveying the receiver on the bottom plate throughout the oven vessel. A microwave generator is operatively connected to the oven vessel for generating microwaves to irradiate the content of the receiver when it passes throughout the oven vessel. The receiver may be rotated and vertically moved when it is subjected to denitration and calcination in the oven vessel.

Abstract: Process for producing low cost, high purity solar grade Si wherein a reduction reaction, preferably the reduction of SiF.sub.4, by an alkali metal (Na preferred) is carried out by jetting a spray of reactants into a reaction chamber at a rate and temperature which causes the reaction to take place far enough away from the entry region to avoid plugging of reactants at the entry region and wherein separation in the melt is carried out continuously from the reaction and the Si can be cast directly from the melt.

Abstract: A process for treating exhaust gas from an electrophotographic machine which comprises oxidizing, in the presence of a heated oxidation catalyst, an odorous exhaust gas generated in course of the steps of developing an element being developed by means of a developer, transferring the thus developed image onto a transfer sheet and/or heating a copy material consisting of said element being developed or said transfer sheet thereby to make said exhaust gas odorless, and an apparatus therefor.

Abstract: In the production of hydrogen from hydrocarbons and water vapor a large portion of the heat which is required for heating the feedstock to the reaction temperature as well as for the endothermic reaction is recovered from the sensible heat of the reaction products. Additional heat is supplied by means of electric heating. An apparatus intended for carrying out the process comprises a recuperator, a reactor chamber and an additional heater housed in a common pressure shell.

Abstract: .beta.-type silicon carbide having exceedingly high purity is stably and continuously produced in an apparatus comprising a vertical type reaction vessel having an inlet, a preheating zone, a heating zone, a cooling zone and a closable outlet which are sequentially communicated in this order in vertical direction, and a heat insulating layer composed essentially of fine powders of graphite and carbonaceous materials arranged on at least outside of the heating zone, the heating zone of the reaction vessel being made of graphite and having a heating means to indirectly and electrically heat charged materials, the preheating zone having a horizontal cross-sectional area larger than that of the heating zone at any level above an arbitrary position of the preheating zone.

Abstract: Oxalic acid, dispersed in glycerol is heated to form formic acid which is then heated at a higher temperature to form hydrogen. By-product carbon dioxide is absorbed. The hydrogen is used directly with a fuel cell to produce electricity or as fuel for an internal combustion engine.

Abstract: A continuous-stream zeolite crystallization apparatus comprising a combination of a tubular reactor, a central stirring element contained therein, ingress and egress means for the reactor for charging crystalline zeolite forming reactants therein and recovering crystallized zeolites therefrom, respectively, recovery vessels for collecting and processing crystallized zeolites continuously, the reactor and recovery vessels optionally being subjected to a controlled pressure system.

Abstract: A system and method of reactivating wet spent activated carbon comprising a batch operated solid-liquid separator, a continuous feed electrically heated furnace and surge bin therebetween. Heat exchangers recover sensible heat of the exhaust gases and/or hot carbon leaving the furnace to heat the air used by the solid-liquid separator. A portion of the furnace exhaust along with added air is recirculated through the furnace to provide the appropriate atmosphere for regeneration of the carbon.

Abstract: An electromagnetic methanol reactor system which includes an enclosed reactor chamber having a pair of electrodes positioned in the chamber and spaced from the walls thereof. An electromagnetic field is generated across the electrodes wherein the field has sufficient strength to atomize oxygen. Methane is continuously supplied to the chamber and oxygen is supplied to the chamber between the electrodes so that the oxygen is atomized. The oxygen combines with the methane to form methanol.

Abstract: An apparatus and method for generating on demand a gaseous product from a liquid phase reaction of one reactant in the solid phase at ambient room conditions and another reactant in the liquid phase at ambient room conditions. The reactants preferably are iodine crystals, and liquid tetrahydronaphthalene (THN), with the gaseous product being hydrogen iodide. The liquid phase reaction, in the preferred embodiment, is 2I.sub.2 +C.sub.10 H.sub.12 .fwdarw.4HI+C.sub.10 H.sub.8, known per se. Preferably, THN is pumped from a reservoir to be sprinkled over the iodine crystals in another reservoir. Some iodine dissolves into the liquid THN, with the resulting solution then percolating through a reaction zone containing a heated, porous packing material. Heat is transferred to the solution, thereby promoting, i.e., driving the above reaction. The gaseous hydrogen iodide is then removed from the reaction zone; typically for direct use, for example, in a chemical laser.

Abstract: A furnace or generator for reacting a hydrocarbon gas which undergoes a reaction having an exothermic phase followed by an endothermic phase, is disclosed. The generator consists of concentric inner and outer tubes having a reacting gas inlet at the top of the inner tube and a reacted gas outlet near the top of the outer tube. The inner tube has holes adjacent its bottom for communicating the bottom of the inner tube with the annular space between the inner tube and the outer tube. The bottom portion of the generator forms a reactor portion while the top portion forms a recuperator portion. A gas air mixture entering near the top of the inner tube is heated in the recuperator portion by the reacted gas in the annular passage. Additional heating means may be provided.

Abstract: An apparatus for decomposing difficultly soluble substances and oxidizing organic wastes which contain difficultly soluble substances, in which the substances and/or wastes are reacted with at least one hot acid, and from apparatus which heat losses are compensated. The apparatus comprises a ring-shaped reaction vessel including at least one horizontally extending region and at least one vertically extending region. A feeder is connected to the vertically extending region for the addition to the reaction vessel of substances and/or wastes, acid, and gas. A degasificaton zone is connected to the horizontally extending region.

Abstract: Methanol is produced from an organic waste material such as sewage by a process wherein an arc heater or "plasma jet" performs novel process steps including: (1) partially vaporizing an organic sewage sludge (a semi-liquid material produced by bacterial digestion of the sewage); (2) reacting the gas products obtained by the sludge vaporization, together with a digester gas (obtained by digestion of the sewage), to form a synthesis gas comprising principally H.sub.2, CO, CO.sub.2, H.sub.2 O and CH.sub.4, and (3) optionally, driving a water shift reaction to convert a portion of the output gases to additional H.sub.2 and CO for use as a feed stream to the jet. The synthesis gas is converted to methanol in a subsequent process step.

Abstract: A pressure controlled vanadium hydride gas generator to provide deuterium-tritium gas in a series of pressure increments. A high pressure chamber filled with vanadium-deuterium-tritium hydride is surrounded by a heater which controls the hydride temperature. The heater is actuated by a power controller which responds to the difference signal between the actual pressure signal and a programmed pressure signal.

Abstract: A process for recovering and recycling elementary silicon from a direct process organohalosilane reactor system is provided, comprising the steps of analyzing a portion of effluent contact mass, such as the silicon fines from a secondary cyclone with a particle size distribution analyzer, determing the fines fractions containing the relatively greatest amounts of impurities and segregating a relatively impure fine fraction from a purer coarse fraction with the aid of an aerodynamic centrifugal classifier.

Abstract: Apparatus for high temperature catalytic conversion of gases is disclosed in which the first part of the heating is done with a heating gas and the final most difficult part is done with electric heaters. The heating gas is passed between spaced layers of catalyst, out of contact and crosswise and countercurrent to the flow of gases to be converted. The gases are first subjected to preheating with heating gas, then heating as the gases contact catalyst, and then superheating, i.e. heating to a final high temperature, with electric heaters in the absence of heating gas.

Abstract: A pyrolytically cleaned domestic cooking oven including a catalyst for combustion of the smoke evolved during cleaning, and a temperature sensor placed inside the catalyst and arranged to regulate the heating control of the oven during pyrolytic cleaning.

Abstract: An apparatus for producing silicon carbide consisting mainly of .beta.-type crystal are disclosed. The fine silicon carbide consisting mainly of .beta.-type crystal is produced by charging the starting material of silica and carbon with a mole ratio of C/SiO.sub.2 of 3.2-5.0 into a top portion of a vertical-type reaction vessel having a preheating zone, a heating zone and a cooling zone in this order, descending the starting material by gravity through the reaction vessel, heating the starting material in the heating zone at a temperature of 1,600.degree.-2,100.degree. C. by electrically indirect heating in horizontal direction to effect the formation of SiC, cooling the resulting reaction product in the cooling zone under a non-oxidizing atmosphere, and recovering the cooled product from the bottom portion of the reaction vessel to obtain a product having a composition ratio by weight of silicon carbide, silica and free carbon which lies within the area represented by the area ABCD shown in Fig.

Abstract: A method and apparatus for the continuous high temperature treatment of sulfur-containing carbonaceous particles in an electrothermally heated fluidized bed is disclosed. In one aspect of the invention, a fluidizing stream is passed through carbonaceous particles introduced into a fluidizing zone at a velocity sufficient to fluidize said carbonaceous particles. The carbonaceous particles are heated in a fluidized state, and controllably fed into and discharged from the fluidizing zone at a rate sufficient to assure that the sulfur content of the particles are reduced below 0.5%. In another aspect of the invention, at least a portion of the carbonaceous material is transformed from a relatively amorphous molecular state, into a graphite crystalline state.

Abstract: The yield of good-quality bodies consisting of vitreous carbon is increased to substantially 100% when the pyrolysis is performed in a reaction vessel in which a collecting container or a collecting disc for the condensable volatile decomposition products which is open at its upper side is arranged above the polymeric substances to be pyrolized. The collecting disc divides the interior of the reaction vessel into two parts, a passage for gases remaining between the upper part and the lower part. During the pyrolysis, a spatial temperature distribution is adjusted in the reaction vessel which results in a pulsating evaporation and condensation of the decomposition products, so that the decomposition products are completely removed.

Abstract: An apparatus for connecting a power supply to an electrode within a high pressure, high temperature vessel is disclosed. The apparatus includes a conductor extending through the vessel such that the net force exerted upon the conductor by the vessel pressure is negligible. An elastomeric material seals the vessel conductor interface and the apparatus cools the sealing material to avoid softening thereof.

Abstract: The method and apparatus for producing liquid silicon of high purity and for casting silicon. Hydrogen and a hydrogenated silane in gaseous state are mixed, preferably with a source of a small amount of oxygen, in a heated chamber producing the liquid silicon, with the exhaust gases bubbling out of the melt under a baffle. The chamber for the melt of liquid silicon preferably is lined with silicon dioxide. The liquid silicon may be used in making high purity vitreous silica and may be used in making castings of silicon. In making castings, the liquid silicon is accumulated in a second chamber and is periodically drawn from the second chamber into a third chamber which contains the mold for the casting.

Abstract: A method and related apparatus are provided for producing on a semi-continuous basis polycrystalline silicon and melt replenishment for a crystal growth crucible. The silicon is deposited in low density form on the inner walls of a multi-walled reaction chamber by delivering gaseous HSiCL.sub.3, SiH.sub.4, or the like, and reducing gas if needed, through the chamber which is heated to the reaction temperature of the feed gas. After a certain amount of silicon has been produced, the chamber temperature is raised sufficiently to melt down the silicon which is then used to replenish a crystal growth crucible. The operations are then cyclically repeated.The apparatus includes a reaction chamber having a multi-walled configuration to maximize the interior surface area on which the silicon is deposited. A drain trap such as a U-shaped tube, or the like, is connected to the bottom of the reaction chamber and provided with heating elements.

Abstract: Low-soda alumina granules suitable for use as an alumina porcelain insulator and alumina catalyst carrier, and the method and equipment for their manufacture. The method comprises dehydrating aluminum hydroxide at a high temperature and then granulating it. The granules thus obtained are placed in an autoclave, washed and cured with water drops, then taken out of the autoclave dried and fired. The manufacturing equipment is used for curing the granules with water drops.

Abstract: The manufacture of hydrogen and oxygen by the dissociation of water vapor at elevated temperatures followed by separation of hydrogen from the water vapor and the oxygen produced using a hydrogen permeable membrane is improved by increasing the surface area of the membrane exposed to the dissociation gas mixture.One way of increasing the surface area of contact, according to the present invention, is to form a hydrogen permeable membrane coated on one side of a porous refractory wafer with an inlet hole through the wafer connecting a beginning of the maze and an outlet at the end of the maze facing the opposite direction from the inlet. A number of these wafers are then stacked or replicated front-to-back with each outlet corresponding to the inlet of the next wafer to give a compact and efficient hydrogen diffusion separator.

Abstract: A unit (10) for disinfecting contact lenses includes a housing, heating means (20) arranged to heat a contact lens case (21) and the contact lenses therein and means (30) for indicating the temperature condition (HOT or COLD) of the lens case. The temperature indicating means includes a viewing window (17) formed in the housing, a prismatic lens (38) within the housing and behind the viewing window, and pivotally mounted indicia (39) behind the prismatic lens that indicates if the lens case is cool enough to handle following the disinfecting heating cycle.

Abstract: A contact lens disinfector unit (10) includes a housing, heating means arranged to heat the contact lenses and the associated lens case (21) to a disinfecting temperature and for thereafter terminating the application of heat to allow the contact lenses to cool, and temperature indicating means (30) for indicating if the lens case is cool enough for safe handling. The temperature indicating means includes a viewing window (17) having opaque portions (38) and transparent portions (37). The transparent portions are arranged to define a temperature indicia. The temperature indicator also includes a plate (35) which has indicia thereon corresponding to the temperature indicia and a surrounding opaque background. The plate is slidable with respect to the viewing window between two positions, one of which indicates that the lens case is too hot to handle, and the other of which indicates that the lens case is cool enough to handle.

Abstract: A contact lens disinfector unit (10) includes a housing having a top wall (15), a heating block (27) within the housing for heating the contact lens case (25) and the lenses therein, and a lens case receiving compartment (26) between the heating block and the top wall (15) having an opening in a side wall (18) of the housing for slidingly receiving the contact lens case. A lens case ejector (28) is slidingly mounted on the housing top wall (15) and includes an elongate member (57) extending into the lens case receiving compartment to provide a key for positioning the lens case base against the heating block. The ejector also forms a pusher (56) to engage the lens case. A barrier wall (27a) isolates the lens case compartment from a cavity (48a) in the housing that contains electrical circuitry. Springs (50) press the lens case against the heating block.

Abstract: The high pressure furnace comprises a cylindrical pressure vessel with front and rear pressure closures. An electrical heating element is supported within the interior of the pressure furnace. The front closure supports a relatively thin-walled inner container opening only to an aperture in the front closure. A small closure plugs the aperture. A reaction frame secures the various closures. Blanket gases are introduced into the furnace chamber and process gases into the process chamber defined by the interior of the inner container. Means are provided for minimizing the pressure difference across the inner container to enable it to maintain its original shape.

Abstract: A high-temperature, fluid-wall chemical reactor can be equipped with a variable profile, counterflow heat exchanger and a reaction product control system. The heat exchanger includes two tubular walls, positioned concentric of one another, and a spiral baffle disposed between the two walls to define a spiral, annular coolant channel. The walls and baffle are made of a refractory material. The heat exchanger has an inlet and an outlet to permit a coolant to be circulated through the coolant channel. The reaction product control system includes a reaction product analyzer and means for withdrawing and transferring samples of reaction product exiting the reactor. The reaction product analyzer can receive samples of reaction product and generate a signal corresponding to deviations between the chemical composition of the product and a preselected composition.

Abstract: Air is pumped from an upper chamber in a cylindrical housing through parallel groups of Ni-Cr steel heating tubes to a lower chamber communicating with a carbon-dioxide adsorber in an air-rectification system. The tube groups are suspended at their upper ends from respective Al.sub.2 O.sub.3 -ceramic holder plates seated on flanges projecting into respective openings of a carrier plate in turn removably fastened to the inside of the housing. The tubes in each group are connected in series with one another to a voltage source, the lower ends of the tubes in a group being gripped by a form-fitted ceramic spacer slidably inserted into a pipe section aligned in a support plate with an associated opening in the upper carrier plate, thereby ensuring the electrical insulation of the tubes. The holder plates and the openings are shaped as circles or as circular sections.

Abstract: Apparatus and method for preparing phosphorus compounds wherein phosphorus vapor containing P.sub.2 molecules is condensed at a temperature below the solidification point of red phosphorus and the resulting solid is then reacted with a phosphorus-reactive material. When the phosphorus-reactive material is water at an elevated temperature, phosphine is produced.

Abstract: An apparatus for the sulfatizing roasting of a selenium-containing raw material, especially the anode slime from copper electrolysis, with sulfuric acid at a raised temperature, the apparatus comprising a furnace chamber having a feed pipe for feeding a slurry of a finely-divided, selenium-containing raw material and sulfuric acid into the furnace chamber, an outlet for withdrawing the roasted solid from the furnace chamber, an outlet for discharging the selenium bearing gases produced during the sulfating roasting, members for heating the slurry in the furnace chamber, and devices for transferring, as a layer, the slurry fed into the furnace chamber from the slurry feed point towards the outlet for solid, the members for transferring the slurry being one or more combinations of a tray which supports slurry and a scraper which scrapes the tray, at least some of the slurry-heating members being mounted in the tray in order to heat it.

Abstract: An apparatus for efficiently and safely recombining hydrogen and oxygen gas to form water vapor, the apparatus being particularly adapted for use with a nuclear reactor system in which potentially dangerous hydrogen gas, evolved within the containment vessel during certain postulated accident conditions, can be eliminated. Further, this apparatus also aids in the removal of certain radioactive contaminents from the gases in a containment vessel.

Abstract: A metal hydride fuel system incorporating a plurality of storage elements that may be individually replaced to provide a hydrogen fuel system for combustion engines having a capability of partial refueling is presented.

Abstract: A heating device for heating corrosive vapours includes a casing defining a vapour flow path having an inlet and an outlet. A tubular metallic electric resistance heating element is disposed in the flow path and arranged such that the vapours being heated successively pass in opposite directions along the interior and exterior of the element in flowing from the inlet to the outlet of the casing. To accomodate thermal expansion and contraction, one end of the element is connected to the casing by means of a flexible coupling there being provision to maintain at least a part of the flexible coupling immersed in a body of an electrically non-conductive liquid capable of shielding the coupling from the corrosive vapours during operation of the device. The non-conductive liquid may be maintained in the liquid state by circulation through a heat exchanger.

Abstract: A bench scale hydrocarbon reactor simulator accurately simulating full scale reactor coking conditions wherein the rate of coking may be measured by maintaining constant temperature of the reactor simulator exit gas by a temperature responsive circuit varying power supplied to a heater, the increase in power to the heater being proportional to deposition of coke on the heater sheath.

Abstract: A reactor-tube assembly for a high-temperature, fluid-wall reactor comprises a reactor tube made of a fabric of a fibrous, refractory material, two support rings positioned at the ends of the reactor tube, and means for securing the ends of the reactor tube to the support rings. Carbon or graphite cloth is a preferred fibrous refractory material out of which to make the reactor tube.

Abstract: A radial-flow reactor, especially for carrying out endothermic, catalytic reactions, which has a closed reactor housing defining a reactor chamber therein, a centrally arranged, first inlet duct for entry of a gaseous reactant stream and a catalyst bed disposed around the duct located within said chamber, and at least one additional outlet duct arranged on the outer rim of the housing for discharge of a gaseous product stream from said reactor chamber. A plurality of heating elements are embedded in the catalyst bed. Each heating element is constructed as a straight heating tube and each tube has one free end projecting into the reactor chamber, with a part adjacent to the other end attached to a base plate. The base plate forms a part of a wall structure defining the reactor chamber within said housing and can be detached from the wall structure. A group of the heating elements is secured to one base plate so that the group of elements and the one base plate can be removed from the reactor together.