Abstract: The present invention relates to a process for preparing largely HBr-free HCl gas and largely HBr-free aqueous HCl solution, which comprises the following steps: a) providing HBr-containing HCl gas; b) passing the HBr-containing HCl gas through aqueous HCl solution saturated with HCl; c) separating off HBr-containing aqueous HCl solution saturated with HCl; d) if desired, passing the largely HBr-free HCl gas obtained in step b) into water to obtain largely HBr-free aqueous HCl solution; with largely HBr-free aqueous HCl solution produced in step d) being able, if desired, to be recirculated to step b) of the process. The process of the present invention allows high-purity aqueous HCl solution for use in the semiconductor industry to be prepared inexpensively and on an industrial scale. However, the purified HCl gas obtained by means of steps a) to c) can also be used for any other purposes. The invention likewise provides an apparatus for carrying out the process of the present invention.

Abstract: Process for the conversion of sodium bromide to anhydrous hydrobromic acid and sodium bisulfate, said process with the following sequential steps: reaction of sodium bromide and sulfuric acid in a solution of water to produce hydrobromic acid and sodium bisulfate wherein the conversion rate is greater than about 95%; separation of hydrobromic acid and water from the sodium bisulfate; separation of hydrobromic acid from water; and drying of hydrobromic acid.

Abstract: This invention relates to a novel method, which can be carried out according to industrial standards, for producing high-purity hydrochloric acid with a very low particle content, for use in the production of semiconductors.

Abstract: A process is disclosed for regenerating an aqueous acid halide leachant from a spent aqueous metal halide leach liquor. The process comprises introducing into a fluidized bed or spray roaster a hydrocarbon fuel, an oxygen-enriched oxidizing gas and the aqueous metal halide leach liquor; pyrohydrolyzing the aqueous metal halide leach liquor by combustion of the hydrocarbon fuel with the oxygen-enriched oxidizing gas to produce an acid halide-containing gas fraction and a metal oxide-containing solid fraction; separating the gas fraction from the solid fraction, recovering heat energy from the acid halide-containing gas fraction and absorbing the gas fraction in water to produce the aqueous acid halide leachant. The oxygen-enriched oxidizing gas has an oxygen concentration of greater than about 21 percent by volume, preferably greater than about 50 percent by volume, more preferably greater than about 80 percent by volume, and even more preferably greater than about 90 percent by volume.

Abstract: A high viscosity liquid is fed into a rotation pack bed at a position with a distance far enough from a rotation axis, creating a centrifugal force exerted on the high viscosity liquid overwhelming a drag thereof, so that it can flow radially through the rotation pack bed. A high pressure gas is introduced into the rotation pack bed peripherally and/or a suction force source is connected to a position near the rotation axis, so that a volatile component contained in the high viscosity fluid is entrained in the gas counter currently flowing through the rotation pack bed and withdrawn from the position near the rotation axis, or the volatile component exits from the position near the rotation axis in gas phase, and thus the volatile component is removed from the high viscosity liquid. A second fluid can also be fed into the rotation pack bed to react with the high viscosity liquid, so that a reaction product is formed, and a volatile side product is removed at the same time.

Abstract: Hydrogen fluoride is effectively removed from a mixture of hydrogen fluoride, dichloromethane, chlorofluoromethane and/or difluoromethane by distilling the mixture so that two-component azeotropic mixtures of hydrogen fluoride and dichloromethane, hydrogen fluoride and chlorofluoromethane and hydrogen fluoride and difluoromethane are removed, or by liquid-separating the mixture into an upper liquid phase rich in hydrogen fluoride and a lower liquid phase not rich in hydrogen fluoride before each liquid phase is distilled as described above.

Abstract: Methods for improving a gasification process for halogenated materials and in particular for producing useful end products such as anhydrous or highly concentrated hydrogen halides and/or synthesis gas, the methods including recycling water/hydrogen halide vapors and/or carbon dioxide to a gasification reactor.

Abstract: The process according to the invention comprises bringing gaseous hydrogen chloride in a non-condensable gas into contact with an absorbing medium selected from water or a dilute aqueous hydrogen chloride solution in an absorption column to cause the medium to absorb the gaseous hydrogen chloride, and subjecting the resultant absorbed solution to distillation in the presence of a salt having a salting-out effect to produce anhydrous hydrogen chloride.

Abstract: Catheter systems and methods for their use in enhancing fluid flow through a vascular site occupied by a vascular occlusion are provided. The subject catheter systems include at least an aspiration catheter and at least one of a total occlusion insert catheter and a partial occlusion insert catheter, where the insert catheters are capable of being slidably moved in the lumen of the aspiration catheter. In practicing the subject methods, a surface of the vascular occlusion is flushed with an acidic dissolution fluid using the subject catheter systems for a period of time sufficient for fluid flow through the vascular site to be enhanced, e.g. increased or established. The subject catheter systems and methods find use in the treatment of a variety of different vascular diseases characterized by the presence of calcified vascular occlusions, including peripheral and coronary vascular diseases.

Abstract: A method for the preparation of a perfluorinated acid fluoride (especially 3-alkoxy propionic acid fluoride) is provided. The method results in high yields of the acid fluoride.

Abstract: A process is described for producing a pipeline-ready anhydrous hydrogen chloride stream from byproduct or waste chlorinated materials, comprising the steps of incinerating the byproduct or waste chlorinated materials, recovering a substantially dry hydrogen chloride product stream from the incineration step, and further drying the substantially dry hydrogen chloride product stream by contact with a desiccant, preferably being dry sulfuric acid.

Abstract: The invention has an object to provide a solid chloride absorbent which can efficiently absorb inorganic chlorides such as hydrogen chloride flowing out from a process in which a heavy naphtha and the like are treated and inorganic chloride derived from crude oil, and which is difficult to powder and soften after absorbing the chlorides. The solid chloride absorbent according to the invention comprises zinc oxide, a porous refractory inorganic matter and an inert binder, has a long life, and hardly releases the absorbed chlorides.

Abstract: The process is by injection of calcium chloride into the combustor and lowering the flue gas temperature in sufficient time to enhance oxidation of mercury and nitrogen oxides into more soluble products prior to their absorption in a wet scrubber. The additive also increases the alkalinity and the pH of the scrubber water, therefore, favorably increasing the absorption of the pollutants. The flue gas is then cooled to ambient temperature or less to enhance the removal of mercury.

Abstract: A process and an apparatus for treating an exhaust gas, in which a raw gas and high-boiling intermediate products contained in the exhaust gas let out from a CVD system employing a silicon-containing gas is brought into contact with a transition metal such as nickel or a silicide of such transition metals to decompose or convert them into stable halides, followed by detoxication treatment of the harmful components contained in the exhaust gas.

Abstract: A process is disclosed for recovering raw materials, in particular heavy metals such as chromium, zinc, copper, lead, or nickel, by separation from waste and residues, wherein a liquid or viscous starting mixture and/or a starting mixture composed of crushed or ground components is first prepared. The invention is characterized in that the raw materials are separated by a thermochemical treatment. The liquid, viscous and/or solid starting mixture is first mixed with additives, depending on its composition, then subjected to a thermal treatment in an oven. The atmosphere in the oven flows through the starting mixture and the suspended materials thus generated as flakes or dust are conveyed out of the oven through a filter installation with several stages in which they are separated from the waste gas. The first filter is designed as a hot filter, after which the waste gas is cooled and after flowing through at least a second filter, pre-heated and then burnt at a high temperature.

Abstract: Catheter systems and methods for their use in enhancing fluid flow through a vascular site occupied by a vascular occlusion are provided. The subject catheter systems include at least an aspiration catheter and at least one of a total occlusion insert catheter and a partial occlusion insert catheter, where the insert catheters are capable of being slidably moved in the lumen of the aspiration catheter. In practicing the subject methods, a surface of the vascular occlusion is flushed with an acidic dissolution fluid using the subject catheter systems for a period of time sufficient for fluid flow through the vascular site to be enhanced, e.g. increased or established. The subject catheter systems and methods find use in the treatment of a variety of different vascular diseases characterized by the presence of calcified vascular occlusions, including peripheral and coronary vascular diseases.

Abstract: A new process of preparing potassium sulfate fertilizer and other metal sulfates from the chlorides and other halides of these metals. The process utilizes the discovery that sulfur dioxide or trioxide, when introduced as a fluidizing medium into shallow beds of the halide salts at moderately elevated temperatures (1000° F.-1150° F.) in a counter current process results in the conversion of the metal halides into metal sulfates and the halide gas. The process is carried out in a series of true fluidized beds preferably but not necessarily arranged in a vertical configuration so that the solids flow downward due to the fluidized process and the sulfur dioxide or trioxide gases flow counter currently in an upward direction producing pure metal sulfates at the bottom and pure halide gas at the top.

Abstract: A process for removing chloride from chloridic iron oxide comprises mixing said chloridic iron oxide with an acid and subsequently conducting a thermal treatment at from 50 to 1300° C.

Abstract: A method for gasification of halogen containing remainders and waste materials is provided including obtaining a reactant including halogen containing remainders and/or halogen containing waste, and where necessary an additional combustible. The reactant has a heat value of greater than 6 MJ/kg and is reacted with a gasification agent containing free oxygen into a crude gas using a flame reaction at a pressure in excess of ambient pressure to a final temperature of at least 1100° C. The crude gas contains carbon monoxide, hydrogen-containing gas and/or halogen/hydrogen containing gas. The crude gas can then be cooled and further processed.

Abstract: The present invention relates to a process for separating hydrogen chloride from a mixture comprising an N-(C1-C18)-alkyl-2-pyrrolidone and hydrogen chloride by distilling the mixture comprising an N-(C1-C18)-alkyl-2-pyrrolidone and hydrogen chloride at from 100 to 220° C. and from 50 to 850 hPa in the presence of water by means of a distillation column, condensing the water as water-hydrogen chloride azeotrope at the top by cooling, returning the water-hydrogen chloride azeotrope to the distillation column, separating off gaseous hydrogen chloride at the top and taking off the N-(C1-C18)-alkyl-2-pyrrolidone from the bottom.

Abstract: A method of removing iron and halogen coloring materials from hydrochloric acid, by removing iron from the hydrochloric acid, and thereafter adding a nitrogen containing reducing agent to the hydrochloric acid.

Abstract: A process is provided for production of substantially pure carbon dioxide from a CO2 off-gas stream from an ethylene glycol plant. Water is condensed from an off-gas stream which contains unsaturated hydrocarbons, saturated hydrocarbons, chlorinated hydrocarbons, carbon dioxide and water. The dewatered gas stream is subjected to catalytic oxidation in the presence of excess oxygen whereby the unsaturated hydrocarbons, saturated hydrocarbons and chlorinated hydrocarbons are oxidized producing an oxidation stream containing carbon dioxide, water and hydrochloric acid. The HCl is removed with an absorbent and substantially pure carbon dioxide is collected. The absorbent-contacted stream can be subjected to catalytic deoxidation in the presence of hydrogen to convert unoxidized oxygen introduced in the catalytic oxidation to water.

Abstract: The invention relates to a process for electrochemically converting anhydrous hydrogen halide, such as hydrogen chloride, hydrogen fluoride, hydrogen bromide and hydrogen iodide, to essentially dry halogen gas, such as chlorine, fluorine, bromine and iodine gas, respectively. In a preferred embodiment, the present invention relates to a process for electrochemically converting anhydrous hydrogen chloride to essentially dry chlorine gas. This process allows the production of high-purity chlorine gas. In this process, molecules of essentially anhydrous hydrogen chloride are transported through an inlet of an electrochemical cell. The molecules of the essentially anhydrous hydrogen chloride are oxidized at the anode of the cell to produce essentially dry chlorine gas and protons, which are transported through the membrane of the cell. The transported protons are reduced at the cathode to form either hydrogen gas, water or hydrogen peroxide.

Abstract: A method and apparatus for decomposing halogenated hydrocarbons are provided. The halogenated hydrocarbon is mixed with solvating agents and maintained in a predetermined atmosphere and at a predetermined temperature. The mixture is contacted with recyclable reactive material for chemically reacting with the recyclable material to create dehalogenated hydrocarbons and halogenated inorganic compounds. A feature of the invention is that the process enables low temperature destruction of halogenated hydrocarbons.

Abstract: The present invention provides a process for producing hydrogen halide and oxygen by a stable chemical reaction for a long time. In this method, hydrogen halide and oxygen are produced by reacting water and halogen as represented with the following formula:H.sub.2 O+X.sub.2 .fwdarw.2HX+1/2O.sub.2 ( 1)(wherein, X represents a halogen), wherein porous silica having a mean pore diameter of 0.7 to 5 nm is used as catalyst. Preferably, hydrophilic functional groups are provided on the surface of said porous silica.

Abstract: Activated carbon is effective as a catalyst for water decomposition when it is coated with a heat-resistant, oxidation-resistant film. The heat-resistant, oxidation-resistant film is formed from an inorganic material such as ceramic or metal, and/or an organic material such as an organic ion-exchange resin, a silicone resin or a fluororesin, and preferably contains oxide capable of decomposing hypohalogenous acid. Water can be chemically decomposed to give hydrogen by the use of the activated carbon.

Abstract: A process for treating a non-distillable halogenated organic feed stream wherein the feed stream is contacted with a hydrogen-rich gaseous stream at hydrodehalogenation conditions to produce a carbonaceous solid containing a reduced halogen content and hydrogen halide gas. The resulting carbonaceous solid is stripped with a second hydrogen-rich gas to recover additional hydrogen halide gas and to produce a carbonaceous solid which is suitable for other uses.

Abstract: A method relates to treating a halogenated organic waste to produce halogen gas and carbon oxide gas streams. The method includes directing a halogenated organic waste, having a halogen-to-hydrogen atomic ratio of less than about one, into a molten metal bath. The molten metal bath is inert to the halogen and has a free energy of oxidation greater than that of the formation of carbon monoxide from atomic carbon. The halogenated organic feed is converted into halogen gas and atomic carbon, whereby the halogen gas is released from the molten metal bath. An oxidant is directed into the molten metal bath, whereby the atomic carbon is oxidized to form a carbon oxide gas, which is released from the molten metal bath.

Abstract: A process for producing refined hydrogen iodide having organic components of 0.2 ppm by volume or less and water of 0.1 ppm by volume or less by contacting crude hydrogen iodide with a zeolite is disclosed. Crude hydrogen iodide is obtained by reducing iodine with a hydrogenated naphthalene, wherein all of the iodine is dissolved in advance in a portion of the hydrogenated naphthalene to prepare an iodine solution, and the reaction is carried out while adding continuously or intermittently the iodine solution to the balance of the hydrogenated naphthalene. The same operation may be repeated in succession using unreacted hydrogenated naphthalene and fresh iodide. The zeolite is contacted in advance with crude hydrogen iodide, the amount of which is at least 1/3 (weight ratio) relative to the amount of the zeolite, to convert impurities of sulfur components contained in the zeolite to hydrogen sulfide, thereby removing the sulfur components.

Abstract: A method and apparatus for preparing high purity hydrogen bromide, wherein a starting hydrogen bromide which contains impurities having low boiling points is supplied to an intermediate space. While the gas phase of the starting hydrogen bromide is allowed to ascend through an upper rectifying section, it is brought into contact with a first reflux solution flowing in the reverse direction. The uncondensed gas stored in an upper space is cooled and partly condensed. The condensed liquid is allowed to flow down through an upper rectifying section as the first reflux solution. The liquid-phase of the starting hydrogen bromide is mixed with the first reflux solution in the intermediate space and serves as a second reflux solution. The liquid stored in a lower space is heated and partly evaporated. The liquid stored in the lower space is supplied outside as high purity hydrogen bromide. The uncondensed gas stored in the upper space is discharged outside.

Abstract: An apparatus and method for producing a product, such as hydrogen halide gas or sulfuric acid, in a regenerator furnace subsystem from a waste containing a non-gasifiable impurity. The method of the invention includes directing a waste, containing a non-gasifiable impurity into a reaction zone, containing a molten metal bath, in a reactor maintained under conditions sufficient to dissociate the waste and to form a gasified feed component and a non-gasifiable impurity. The gasified feed component is then directed from the reactor to a regenerator furnace subsystem, maintained under conditions sufficient to convert the gasified feed component to the desired product.The apparatus of the invention includes a reactor having a waste inlet and a gaseous effluent, a reaction zone containing a molten-metal bath for dissociating the waste, containing a non-gasifiable impurity, and forming a gasified feed component, and a lance for injecting the waste into the reaction zone.

Abstract: Regeneration of hydrochloric acid by hydrolysis of iron chloride in aqueous solution employs a Pelletiser (5) after preconcentration of acid solution in a "Pre-Evaporator" (1). Pelletiser (5) controls pellet mixture to between 12% and 14% free water by recycling dried solids from Roaster (3), from Screen (7), or from dust removal Cyclone (9), and waste liquid from Preconcentrator (1). Preconcentrator (1) is contacted with superheated gas from Fluid Bed Roaster (3). Rotary Drier (6) dries pellets with a concurrent hot gas stream and the pellets are screened at (7) with oversize being sent to a Mill (8), undersize recycled to Pelletiser (5), and sized feed delivered to Roaster (3). HCl is produced as gas offtake from Preconcentrator (1) and passes via a demisting Cyclone into adiabatic Absorption Process section (11), where weak acid liquor and water (10) are added as required.

Abstract: An HCl adsorbent, and method of making and using the adsorbent, the adsorbent comprising an activated alumina promoted with an alkali metal in an amount such that if calculated as alkali metal oxide, the adsorbent contains at least about 5% by weight alkali metal oxide. The adsorbent is used for removal of HCl from a fluid stream.

Abstract: Waste gases are purified by adding reagent and/or absorbent which reacts with pollutants in the gases to the gases, and then introducing the gases into a wetting reactor for activating the reagent or absorbent contained in the gases. The gases are introduced into a drying zone of the reactor and then passed upwardly into a wetting zone. The reagent or absorbent which has reacted partly or completely with the pollutants is separated from the gas by a filter in the upper section of the reactor and particles are intermittently detached from the filter and fall downwardly into an ash layer in the bottom of the reactor. The ash layer is capable of homogenizing wet particles and water droplets which fall downwardly from the wetting zone, and typically is at least about 25 cm thick. A mechanical mixer/grinder may be provided in the ash layer for mixing the particles and droplets and grinding lumps in the ash layer into particles.

Abstract: A process of pyrolyzing plastic waste feed streams containing polyvinyl chloride, polyethylene terephthalate, polystyrene and polyethylene to recover polystyrene HCl and terephthalic acid comprising: heating the plastic waste feed stream to a first temperature; adding an acid or base catalyst on an oxide or carbonate support; heating the plastic waste feed stream to pyrolyze polyethylene terephthalate and polyvinyl chloride; separating terephthalic acid or HCl; heating to a second temperature to pyrolyze polystyrene; separating styrene; heating the waste feed stream to a third temperature to pyrolyze polyethylene; and separating hydrocarbons.

Abstract: A process for disposing of bromofluorocarbons, bromochlorofluorocarbons, or mixtures of any of bromofluorocarbons, bromochlorofluorocarbons, fluorocarbons, or chlorofluorocarbons. The process comprises thermally cleaving halons, halon-containing fluorocarbons, or halon containing chlorofluorocarbons, cooling the resulting gas stream, oxidizing the resulting hydrogen bromide to bromine by feeding excess elemental chlorine into the gas stream, absorbing the resulting HF or HCl from the gas stream with recovery of hydrofluoric acid or hydrochloric acid, and finally separating elemental bromine and chlorine from each other by distillation or reducing both to give the salts.

Abstract: Unreacted phosphorus and heavy metals, such as arsenic and antimony, are removed in environmentally acceptable form from the non-aqueous still bottoms residue resulting from the production of PCl.sub.3, by reacting the residue with an excess of calcium hydroxide in the form of an aqueous lime slurry and separating the reaction product into a precipitate and a filtrate. The reaction with lime slurry may be preceded by hydrolysis with water. The precipitate passes the Toxicity Characteristic Leaching Procedure (TCLP) test and the filtrate contains less than 5 ppm of the heavy metals, thus permitting disposal by landfill and sewering, respectively, under EPA regulations.

Abstract: A two step method of converting ferrous chloride from a pickling liquor to produce hydrochloric acid and ferric sulfate is disclosed. The ferrous chloride is first mixed with sulfuric acid to produce ferrous sulfate and HCl. The HCl is carried to an absorbtion tower where most of the HCl is collected and the remainder is returned to the reactor. The ferrous sulfate is separated from the sulfuric acid. The unreacted sulfuric acid is returned to the reactor and the ferrous sulfate is transported to a second reactor where it is reacted with sulfuric acid and air (O.sub.2) to produce ferric sulfate. The ferric sulfate is removed from the second reactor. Both reactions are carried out at relatively low temperatures under atmospheric pressures.

Abstract: The invention relates to a process for electrochemically converting anhydrous hydrogen halide, such as hydrogen chloride, hydrogen fluoride, hydrogen bromide and hydrogen iodide, to essentially dry halogen gas, such as chlorine, fluorine, bromine and iodine gas, respectively. In a preferred embodiment, the present invention relates to a process for electrochemically converting anhydrous hydrogen chloride to essentially dry chlorine gas. This process allows the production of high-purity chlorine gas. In this process, molecules of essentially anhydrous hydrogen chloride are transported through an inlet of an electrochemical cell. The molecules of the essentially anhydrous hydrogen chloride are oxidized at the anode of the cell to produce essentially dry chlorine gas and protons, which are transported through the membrane of the cell. The transported protons are reduced at the cathode to form either hydrogen gas or water.

Abstract: A continuous process for purifying an off-gas which contains CO.sub.2 and HCl and COCl.sub.2. The process comprises passing the off-gas through a separator filled with N,N-dialkylformamide and HCl. This causes a reaction between the COCl.sub.2 and the N,N-dialkylformamide to give the Vilsmeier complex (adduct of COCl.sub.2 and dialkylformamide) and CO.sub.2. The CO.sub.2 leaving the separator contains small amounts of HCl.

Abstract: The invention relates to a process for the decomposition of polyhalogenated aliphatic compounds having 1 to 8 carbon atoms, polyhalogenated cycloalkyl compounds having 5 to 8 carbon atoms and polyhalogenated aromatic compounds having at least 5 carbon atoms. A contaminated substrate or the polychlorinated compounds per se are heated with a suitable catalyst to 150.degree. to 550.degree. C. The process according to the invention is especially suitable for the decomposition of polychlorinated dibenzodioxins and dibenzofurans in soils, scrap loads and waste gases and for decontaminating filter dust from refuse and waste incineration plants.

Abstract: An improved method for the dechlorination of polychlorinated biphenyls that are dissolved in an organic solvent, which comprises the incremental additions of a hydrogen transfer agent, such as potassium formate, in the presence of a catalytic amount of a hydrogenation catalyst, such as palladium supported on carbon, and water.

Abstract: The invention provides a process for hydrotreating an organic feedstock containing oxygen compounds and a halogen component by means of removing the oxygen compounds with an adsorbent and then contacting the resulting organic feedstock having a reduced concentration of oxygen compounds and a gaseous recycle stream containing hydrogen with a hydrogenation catalyst in a hydrogenation reaction zone to produce an anhydrous liquid stream comprising hydrogenated hydrocarbonaceous compounds having a reduced concentration of halogen and a hydrogen halide compound. The resulting effluent from the hydrogenation zone is optionally separated to produce a hydrogenated hydrocarbonaceous stream having a reduced level of halogen and an anhydrous stream comprising a hydrogen halide compound.

Abstract: A process is described by which numerous waste or by-product aqueous hydrochloric acid streams can be purified by contacting the aqueous hydrochloric acid with a polystyrenic based resin to remove silicon containing impurities and thereby allowing the hydrochloric acid to be re-used for various applications.

Abstract: Halogen-containing waste gases resulting from the dry etching step of the process of fabricating semiconductor devices are rendered harmless by removing the halogen compounds concomitant with said waste gases. Waste gases containing halogen compounds are treated by bringing them into contact first with activated carbon and then into contact with a member selected from the group consisting of an alkali agent and a ferric oxide, at a linear velocity of about 3-50 cm/min at ambient temperature, volume ratios of said activated carbon to the alkali agent or the ferric oxide in terms of a substantially dried base being about 2-4, and said alkali agent being selected from a group consisting of calcium hydroxide, calcium oxide, magnesium hydroxide and magnesium oxide.

Abstract: There is disclosed a process for the controlled hydrolysis of phosphorus trichloride which avoids the formation of lower oxides of phosphorus, phophines and diphosphines wherein phosphorus pentachloride is added to the phosphorus trichloride from about 20 to about 90 percent by weight of the phosphorus trichloride and then water in the form of finely divided droplets is added over the surface of the phosphorus trichloride while the temperature is controlled to below about 80.degree. C.

Abstract: An excellent method of decomposing flon is provided which can decompose flon economically with high decomposition efficiency without necessitating high temperature and high pressure by contacting a gas containing a flon with a catalyst at a condition of a temperature of not less than 200.degree. C. and space velocity of not over than 50,000 (hr.sup.-1).

Abstract: To remove phosgene from off-gases, the former is reacted in a washing zone with a liquid which contains or is composed of compounds of the formula ##STR1## where R.sub.1 and R.sub.2 are identical or different and are each aliphatic or cycloaliphatic alkyl of 1 to 8 carbons, or R.sub.1 and R.sub.2 are --(CH.sub.2).sub.n -- where n is 4 or 5, R.sub.3 is hydrogen or aliphatic or cycloaliphatic alkyl of 1 to 6 carbon atoms, or R.sub.1 or R.sub.2 and R.sub.3 are --(CH.sub.2).sub.m -- where m is 3, 4 or 5.The liquid can be regenerated by the addition of water, and the regenerated liquid can be returned to the washing zone.

Abstract: The invention relates to a process for electrochemically converting anhydrous hydrogen halide, such as hydrogen chloride, hydrogen fluoride, hydrogen bromide and hydrogen iodide, to essentially dry halogen gas, such as chlorine, fluorine, bromine and iodine gas, respectively. In a preferred embodiment, the present invention relates to a process for electrochemically converting anhydrous hydrogen chloride to essentially dry chlorine gas. This process allows the production of high-purity chlorine gas. In this process, molecules of essentially anhydrous hydrogen chloride are transported through an inlet of an electrochemical cell. The molecules of the essentially anhydrous hydrogen chloride are oxidized at the anode of the cell to produce essentially dry chlorine gas and protons, which are transported through the membrane of the cell. The transported protons are reduced at the cathode to form either hydrogen gas or water.

Abstract: A downcomer used to direct hot flue gases from oxidative combusion of halocarbons into an aqueous medium in a quench tank has improved corrosion resistance when made of rhenuim, molybdenum, or an alloy containing at least 50 wt % molybdenum and having a corrosion rate not exceeding 0.254 mm/yr.