Daikin Industries, Ltd.

Masayoshi Imoto

Toshikazu Yoshimura

Akikazu Tabuchi

Arata Sasatani

Takashi Shibanuma

Toshiyuki Kinoshita

Tatsuo Nakada

Satoshi Ide

The present invention provides a novel method for producing hydrogen fluoride which can suppress the occurrence of the pasty state over the whole process of producing hydrogen fluoride, reduce the problem of corrosion caused by sulfuric acid, and improve energy efficiency of the process. A method for producing hydrogen fluoride by reacting calcium fluoride and sulfuric acid comprises: (a) mixing and reacting calcium fluoride and sulfuric acid such that a mixture comprising calcium fluoride particles and sulfuric acid substantially maintains a form of particulate to obtain hydrogen fluoride while supplying sulfuric acid to the calcium fluoride particles at a flow rate of 0.002 to 1 mol/min relative to 1 mol of calcium fluoride to such an amount that a molar ratio of sulfuric acid/calcium fluoride is 0.9 to 1.1.

Method for producing hydrogen fluoride

The present invention provides a novel method for producing hydrogen fluoride, which is capable of using various calcium fluoride sources and preventing a second pasty state from occurring, effectively. In a method for producing hydrogen fluoride by reacting calcium fluoride with sulfuric acid, following steps are conducted: (a) a step for mixing and reacting calcium fluoride particles having an average particle diameter of 1-40 &#x3bc;m with sulfuric acid at a sulfuric acid/calcium fluoride molar ratio of 0.9-1.1 under a temperature of 0-70&#xb0; C. to obtain a solid-state reaction mixture; and (b) a step for heating the solid-state reaction mixture to a temperature of 100-200&#xb0; C. to react with itself, and thereby producing hydrogen fluoride in a gas phase.

A mixture comprising at least 1,1,1,3,3-pentafluoropropane and 1,1,1-trifluoro-3-chloro-2-propene is subjected to a distillation operation, and thereby, a distillate comprising an azeotropic composition consisting substantially of 1,1,1,3,3-pentafluoropropane and 1,1,1-trifluoro-3-chloro-2-propene is obtained and a bottom product comprising 1,1,1,3,3-pentafluoropropane or 1,1,1-trifluoro-3-chloro-2-propene which each is separated and purified.

Azeotropic composition, comprising 1, 1, 1, 3,3-pentafluoropropane and 1, 1, 1-trifluoro-3-chloro-2-propene, method of separation and purification of the same, and process for producing 1, 1, 1,3,3-pentafloropropane and 1, 1, 1-trifluoro-3-chloro-2-propene

A liquefied gas is transfer filled by drawing out a nonazeotropic mixture stored in a first container and containing at least two liquefied gases differing in boiling point as essential components from a liquid phase thereof. The mixture is then transferred filled into a second container. The first container is filled with a supplement liquid or supplement gas in an amount making up for the portion of the capacity of the first container that is equal to the decrease in volume of the liquid phase of the nonazeotropic mixture resulting from transfer filling. The supplement liquid is the liquid phase of the liquefied gas mixture having the same composition as that of the nonazeotropic mixture stored in the first container. The supplement gas is a gaseous phase of a liquefied gas mixture having the same composition as that of the nonazeotropic mixture stored in the first container or a gaseous phase composed of at least one component of the nonazeotropic mixture and containing the component having the lowest boiling point of all of the components of the mixture in a proportion larger than the proportion in the nonazeotropic mixture. Alternatively, the supplement gas may be a compressed gas.

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Osaka, Japan

Masayoshi Imoto