A dehydration method in accordance with an embodiment of the present invention includes: a first dehydration step of bringing hydrogen chloride gas (21) and concentrated sulfuric acid (13A) into contact with each other; and a second dehydration step of bringing hydrogen chloride gas (21A) that has been obtained through the first dehydration step into contact with concentrated sulfuric acid (13B). A concentration of the concentrated sulfuric acid used in the second dehydration step is higher than a concentration of the concentrated sulfuric acid used in the first dehydration step.

Provided is a preparation method and use method of a material for deep purification of HF electronic gas. A metal fluoride-loaded activated carbon material AC/MFx.nH20 is prepared, and a mixed gas flow of carbonyl fluoride and high-purity nitrogen is used to deeply dehydrate the material to obtain the material for deep purification of HF electronic gas AC/MFx. This kind of material has fluoride that can form crystal water to form hydrated metal fluoride, and has strong water absorption properties. Moreover, the anhydrous fluoride and activated carbon do not have to face the problem of being corroded by HF, and the collapse of framework structure and the secondary pollution to HF from reaction products would not be caused. The material has the advantages of high purity and extremely low moisture content when being used for efficiently removing moisture in HF.

Described are boron oxide-containing adsorbents that include porous adsorbent base and boron oxide on surfaces of the base, as well as devices that include the boron oxide-containing adsorbent, and related methods of preparing and using the boron oxide-containing adsorbent.

The present invention relates to a method for producing a molding catalyst for obtaining chlorine (Cl.sub.2) through an oxidation reaction of hydrogen chloride (HCl), and more specifically, to a method for producing an oxidation reaction molding catalyst by adding heterogeneous material to a ruthenium oxide (RuO.sub.2)-supported catalyst having titanium oxide (TiO.sub.2) as a supporting body, and molding so as to be usable in a fixed bed reactor to produce chlorine (Cl.sub.2) from hydrogen chloride (HCl).

The present description relates to a process for producing magnesium metal from dihydrate magnesium chloride comprising the steps of dehydrating MgCI.sub.2.2H.sub.2O with anhydrous hydrochloric acid (HCI) to obtain anhydrous magnesium chloride in an inert environment, releasing the mixture of hydrous HCI and protection gas; and electrolyzing the anhydrous magnesium chloride in an electrolytic cell fed with hydrogen gas under free oxygen atmosphere content, wherein magnesium metal and anhydrous hydrogen chloride are produced, wherein a part of the hydrous HCI is passed through a scrubbing unit to obtain a hydrochloric acid solution, the other part of the hydrochloric chloride gas is dehydrated by contact with a desiccant agent in a drying unit to produce anhydrous HCI, and wherein the anhydrous HCI produced by at least one of the electrolytic cell and the drying unit is reused to dehydrate the of MgCI.sub.2.2H.sub.2O.

A method of separating a composition containing at least one organofluorine compound from at least one inorganic compound by contacts the composition with a semipermeable membrane. Other methods separate a organofluorine compound from a composition containing at least one other organofluorine compound or chlorocarbon. Methods also include isolating a single organofluorine compound from a composition comprising a mixture of organofluorine compounds, chlorocarbons, and/or inorganic compounds.

A method is disclosed for recovering a useful gas from a gas mixture including a useful gas and at least one secondary gas. The gas mixture is first compressed and transferred into a pressure vessel where cooling occurs. Then, from the pressure vessel, a secondary-gas containing gas phase is removed and condensed useful gas is transferred into a purification vessel. In the purification vessel, the condensed useful gas is then purified. A plant is disclosed for recovering a useful gas from a gas mixture. Finally, the use of a plant for carrying out a method for recovering a useful gas from a gas mixture is disclosed.

A method for producing fluorine gas including a fluorination step of obtaining a reaction mixture containing a major fluorinated substance that is a target component generated by fluorination of a raw material compound and by-product hydrogen fluoride, a separation step of separating the reaction mixture to obtain a main product component containing the major fluorinated substance and a by-product component containing the by-product hydrogen fluoride, a purification step of purifying the by-product component to obtain a recovered hydrogen fluoride component in which a concentration of an organic substance is reduced and a concentration of the by-product hydrogen fluoride is increased, an electrolysis step of performing electrolysis using the recovered hydrogen fluoride component as at least a part of an electrolyte to produce fluorine gas, and an introduction step of introducing the fluorine gas obtained in the electrolysis step into a reaction field for fluorination in the fluorination step.

The invention relates to a method for cleaning corrosive process gases that contain sulfur compounds. According to the method, a gas stream that contains corrosive gases is conducted, in a sorption phase, over an inorganic sorbent material which absorbs at least one of the sorbable sulfurous components on the sorbent material, and the sulfurous compound-depleted gas stream is removed.

The invention relates to a method for separating chlorine from a gaseous anode outlet stream mass flow of an electrochemical cell reactor. In a first aspect, the method makes use of an absorption step, wherein an anode outlet stream mass flow of the electrochemical cell reactor is exposed to an organic solvent being essentially immiscible with water for achieving an exergy-efficient separation of chlorine and hydrogen chloride. In a further aspect, the method makes use of absorption step, wherein the anode outlet stream mass flow is exposed to an ionic liquid, wherein the hydrogen chloride is dissolved in said ionic liquid, thereby forming a gas flow containing essentially chlorine and a solution mass flow comprising the ionic liquid and the hydrogen chloride. The hydrogen chloride is desorbed from the solution mass flow in a desorption step. In another aspect, the method makes use of a distillation step, wherein the anode outlet stream mass flow is separated at a static pressure of at least 2 bar for an exergy-efficient separation.