Provided is a method for producing a working medium containing difluoroethylene, the difluoroethylene not having self-decomposition properties.

A method for producing a working medium containing difluoroethylene.

An object is to suppress the polymerization reaction or self-decomposition reaction of 1,2-difluoroethylene. Provided as a means for achieving the object is a method for allowing 1,2-difluoroethylene (HFO-1132) and oxygen to coexist in a gas phase, the concentration of oxygen in the gas phase at a temperature of 25° C. being 1000 volume ppm or less.

An object is to suppress the polymerization reaction or self-decomposition reaction of 1,2-difluoroethylene. Provided as a means for achieving the object is a method for allowing 1,2-difluoroethylene (HFO-1132) and oxygen to coexist in a gas phase, the concentration of oxygen in the gas phase at a temperature of 25° C. being 1000 volume ppm or less.

Disclosed is a method of purifying a stream of crude hydrochlorofluoroolefin refrigerant produced by the reaction of 1,1,3,3 tetrachloropropene (R1230za) or 1,1,1,3,3-pentachloropropane (R240fa) with HF. The process includes a step of removing the cis-(Z) isomer by distillation of the crude refrigerant stream prior to a step of reacting the crude refrigerant stream with a base. The reaction with the base is a necessary step in production of the refrigerant and is done to remove HF and residual HCl from the crude refrigerant stream. Removal of the cis-(Z) isomer before the reaction with the base reduces the amount of toxic flammable trifluoropropyne (TFP) that is produced as a side-reaction during the reaction with the base. In addition, temperature control during the reaction with the base is less critical to minimizing the TFP production if the cis-(Z) isomer is first removed.

Disclosed is a method of purifying a stream of crude hydrochlorofluoroolefin refrigerant produced by the reaction of 1,1,3,3 tetrachloropropene (R1230za) or 1,1,1,3,3-pentachloropropane (R240fa) with HF. The process includes a step of removing the cis-(Z) isomer by distillation of the crude refrigerant stream prior to a step of reacting the crude refrigerant stream with a base. The reaction with the base is a necessary step in production of the refrigerant and is done to remove HF and residual HCl from the crude refrigerant stream. Removal of the cis-(Z) isomer before the reaction with the base reduces the amount of toxic flammable trifluoropropyne (TFP) that is produced as a side-reaction during the reaction with the base. In addition, temperature control during the reaction with the base is less critical to minimizing the TFP production if the cis-(Z) isomer is first removed.

The present invention discloses a radiative cooling device and a method of manufacturing the same. Specifically, the radiative cooling device according to an embodiment of the present invention includes a reflective layer formed on a substrate and responsible for reflecting sunlight having wavelengths corresponding to ultraviolet, visible, and near-infrared regions; and a radiative cooling layer formed on the reflective layer and responsible for absorbing sunlight having a wavelength corresponding to a mid-infrared region and emitting the sunlight as heat, wherein the radiative cooling layer includes a first radiation layer including an uneven pattern; and a second radiation layer formed on the first radiation layer and having a refractive index different from that of the first radiation layer.

The invention relates to a process for reducing the concentration of a fluorinated alkyne impurity, such as 3,3,3-trifluoropropyne (TFPY), in 2,3,3,3-tetrafluoropropene (HFO-1234yf) which comprises contacting such a mixture with a caustic material, such as sodium hydroxide (NaOH), under conditions effective to reduce the concentration of the fluorinated alkyne impurity, including in some practices reducing the concentration by at least about 50%.

The invention relates to a process for reducing the concentration of a fluorinated alkyne impurity, such as 3,3,3-trifluoropropyne (TFPY), in 2,3,3,3-tetrafluoropropene (HFO-1234yf) which comprises contacting such a mixture with a caustic material, such as sodium hydroxide (NaOH), under conditions effective to reduce the concentration of the fluorinated alkyne impurity, including in some practices reducing the concentration by at least about 50%.

A storage method of HCFO-1233zd (Z) according to an embodiment of the present invention, includes using a storage container having a liquid-contact portion thereof. The liquid-contact portion is formed of a material selected from the group consisting of epoxy-phenolic resin, phenolic resin, phenolic-butyral resin, stainless steel, iron phosphate, zinc phosphate and glass.

A storage method of HCFO-1233zd (Z) according to an embodiment of the present invention, includes using a storage container having a liquid-contact portion thereof. The liquid-contact portion is formed of a material selected from the group consisting of epoxy-phenolic resin, phenolic resin, phenolic-butyral resin, stainless steel, iron phosphate, zinc phosphate and glass.