129 results about "Chlorodifluoromethane" patented technology

The invention relates the multicomponent mixed working substance used for preparing dual-temperature by single-machine vapor compression refrigerator. The low temperature is between -60- -40Deg.C and the high temperature is between -25- 10Deg.C. The multicomponent mixed working substance comprises lower boiling working substance and high boiling working substance. The lower boiling working substance comprises tetrafluoromethane, ethylene, ethane, fluoroethylene, trifluoromethane, fluoromethane, hydrofluoeic ether, carbon dioxide, difluoromethane and penfluoroethane; the high boiling working substance comprises trifluoro-thane, hydrofluoeic ether, propylene, propane, perfluoropropylamine, propadiene, cyclopropane, difluo-monochloromethane, penta-monochloroethane, perfluoroethane, difluoroethane, isobutene, butane, butylenes, isobutylene, sevofluoropropane, hexafluoropropane, penfluoropropane and tetrachloromonofluoroethane.

The present invention relates to a refrigerant composition of four-constituent system, comprising: (a) a first constituent of difluoromethane, (b) a second constituent of 1,1,1,2,3,3,3-heptafluoropropane, (c) a third constituent selected from the group consisting of 1,1,1,2-tetrafluoroethane and 1,1-difluoroethane and (d) a for the constituent selected from the group consisting of isobutane, 1,1,1,2,3,3,-hexafluoropropane and butane, useful as a substitute for chlorodifluoromethane (HCFC-22).

The invention relates to a method for refining a chlorine hydride byproduct and recovering trifluoromethane in production of monochlorodifluoromethane. Refined high-purity chlorine hydride can directly serve as a raw material for synthesizing vinyl chloride monomers; and the trifluoromethane byproduct separated in the refining process can be effectively recovered, wherein the refining of the HCl comprises the following steps of: crude separation, absorption, analysis, condensation, capture of acid mist, and adsorption; and after a F23 byproduct in the production of the monochlorodifluoromethane is separated in the absorption process in the refining of the HCl, the F23 byproduct is subjected to lossless compression and rectification to form the trifluoromethane with the purity of over 99 vol percent. By combining the recovery and comprehensive utilization of the HCl and the recovery of the trifluoromethane, the high consumption of water resources and liquid caustic soda is avoided, and the production cost of the monochlorodifluoromethane is reduced; and the effective recovery of the trifluoromethane prevents environmental pollution, and the chloroalkali, the monochlorodifluoromethane and polyvinyl chloride (PVC) can be circularly produced.

Methods of developing or removing a select region of block copolymer films using a polar supercritical solvent to dissolve a select portion are disclosed. In one embodiment, the polar supercritical solvent includes chlorodifluoromethane, which may be exposed to the block copolymer film using supercritical carbon dioxide (CO₂) as a carrier or chlorodiflouromethane itself in supercritical form. The invention also includes a method of forming a nano-structure including exposing a polymeric film to a polar supercritical solvent to develop at least a portion of the polymeric film. The invention also includes a method of removing a poly(methyl methacrylate-b-styrene) (PMMA-b-S) based resist using a polar supercritical solvent.

The invention discloses a device and a method for purifying trifluoromethane. The device comprises a rectification device and an adsorption device connected with the rectification device, wherein the rectification device comprises a first-stage rectification device, a second-stage rectification device and a third-stage rectification device which are connected in sequence; the adsorption device comprises a low-temperature adsorption device and a filling device which are connected in sequence; the low-temperature adsorption device of the adsorption device is connected with the rectification device. Compared with the prior art, the purity of trifluoromethane purified by adopting the device is relatively high, the device is easy to operate, and a purification process is complete, reliable and good in repeatability. The removal of conventional impurities is considered, difficultly removed carbon dioxide, monochlorodifluoromethane, pentafluoroethane, water and particles are removed to be in a qualified range, and the product purity is 99.999% and meets the use requirements of the semiconductor industry.

The invention provides a preparation method of 2, 3, 3, 3-tetrafluoropropene, which comprises the following steps: taking monochlorodifluoromethane (R22) and methane chloride (methyl chloride) as raw materials and carrying out thermal cracking reaction at a high temperature of 600-1000 DEG C under the condition that N2 exits to prepare the 2, 3, 3, 3-tetrafluoropropene, wherein the volume ratio of the monochlorodifluoromethane to the methane chloride is 1-3:1, and the retention time of a reactant is 0.01-0.2 seconds. The reaction raw material used in the preparation method is easy to obtain, the defect of high cost of the used raw material in the prior art is overcome, the production cost is greatly reduced, and the reaction process is simple. The prepared 2, 3, 3, 3-tetrafluoropropene has the advantages of zero ODP and low GWP and can be used as a substitute of an automotive air-conditioning refrigerant.

A process for obtaining low temperature refrigeration in an existing or new low temperature refrigeration system designed to operate with, or suitable for use with, or capable of being used with HCFC-22 as the refrigerant, the refrigerant composition being a refrigerant composition comprising difluoromethane (HFC-32), pentafluoroethane (HFC-125) and tetrafluoroethane (HFC134a), the three components being present in the composition in amounts such that the operating characteristic of the refrigerant composition in regard to superheat is provided at an acceptable level and the operating characteristics of the refrigerant composition in regard to cooling capacity, mass flow and efficiency (COP) characteristics, when employed as the refrigerant in a low temperature refrigeration system, are each at least 95% of the operating characteristics of chlorodifluoromethane (HCFC-22) if HCFC-22 were to be employed as the refrigerant in such low temperature refrigeration system.

The invention discloses a method for recovering hydrogen chloride gas in production process of chlorodifluoromethane. The organic mixture of hydrogen chloride obtained in the chlorodifluoromethane production process and chlorodifluoromethane is led into a hydrogen chloride rectifying tower; after rectifying, hydrogen chloride is discharged from the top of the tower; the obtained hydrogen chloride is condensed to obtain liquid-phase hydrogen chloride and gas-phase hydrogen chloride, wherein, the liquid-phase hydrogen chloride flows back to the rectifying tower, and trace of fluorinion of the gas-phase hydrogen chloride is removed by a subsequent defluorination device so as to obtain hydrogen chloride gas. The invention can effectively recover by-product hydrogen chloride gas in the chlorodifluoromethane production process and comprehensively utilize hydrogen chloride gas to make waste profitable; in addition, the invention prevents parts of hydrogen chloride gas from volatilizing, prevents hydrochloric acid from polluting ambient environment and prevents hydrochloric acid from corroding devices and ducts.

The present invention discloses one kind of multicomponent mixture work medium suitable for fractional condensation type heat pump circulation system. The mixture work medium or mixed refrigeratant consists of two components, including one low boiling point component and one high boiling point component. The low boiling point component is one or several selected from difluro methane, trifluoro ethane, fluoro ethane, propylene, propane, pentafluoro ethane, etc. The high boiling point component is one or several selected from isobutane, n-butane, butene, isobutene, octafluoro isobutene, octafluoro cyclobutane, etc.

A method for the purification of pharmaceutical grade 1,1,1,2-tetrafluoroethane (HFC-134a) and polymer grade chlorodifluoromethane (HCFC-22) by contacting a mixture comprising 1,1,1,2-tetrafluoroethane or chlorodifluoromethane and methyl chloride with a zeolite such as a molecular sieve, and recovering from said contacted mixture substantially purified 1,1,1,2-tetrafluoroethane or chlorodifluoromethane.

This invention discloses a method for recovering hexafluoropropylene from the azeotrope of hexafluoropropylene and difluorochloromethane during tetrafluoroethylene production process. The method comprises primary distillation, extractive rectification and major rectification. The method has such advantages as high hexafluoropropylene recovery rate (higher than or equal to 97.8 vol. %), low solvent loss (lower than 1.1 kg/h), and high hexafluoropropylene quality (99.99 vol. %).

The invention discloses a preparation method for a roflumilast intermediate. The preparation method is characterized by comprising the following steps of: etherifying 3,4-dihydroxy benzaldehyde serving as a raw material and 3-hydroxyl by using benzene ring non-substituted, mono-substituted or poly-substituted benzyl protection 4-hydroxy and halogenated methyl cyclopropane; performing catalytic hydrogenolysis to obtain 4-hydroxy-3-cyclopropyl methoxy-benzaldehyde; etherifying and oxidizing the 4-hydroxy-3-cyclopropyl methoxy-benzaldehyde with difluoromonoch-loromethane to obtain 3-cyclopropyl methoxy-4-difluoromethoxybenzoic acid (I) serving as the roflumilast intermediate. The preparation method has the advantages of easiness and convenience for operating, mild reaction conditions, stable quality, simple post-treatment and no need of complex operation such as column chromatography and the like, and is suitable for industrial production.

This invention relates to a separation and recovery method of chlorodifluoromethane / hexafluoropropylene azeotrope. The invention adopts one or multilevel membrane separation process. The chlorodifluoromethane / hexafluoropropylene azeotrope transits first order gas separation membrane assembly by gaseity; permeating gas that rich in chlorodifluoromethane enter secondary membrane separation assembly, then reclaimd to compressor first order import buffer tank of tetrafluoroethylene production process; the removeing extraction rectifier unit of firsts and seconds seeping residual air that rich in hexafluoropropylene could gain hexafluoropropylene that purity is greater than 99.9%.

The invention discloses a method for membrane separating gas mixture of difluo-monochloromethane and trifluoromethane, belonging to the fluorin-containing organic steam separation field. The gas mixture of difluo-monochloromethane and trifluoromethane, which is unseparated after condensation during producing refrigerants R22, passes through a gas membrane separation equipment under ambient temperature and pressure, difluo-monochloromethane first penetrates through a gas separation membrane to the other side, the gas mixture is divided into two section by the gas separation membrane, the collected difluo-monochloromethane penetration gas is compressed and reflowed into a refvigeratory-tower, difluo-monochloromethane is cooled, Liquefied and recoveried as the product, high-concentration trifluoromethane penetration gas can be directly sent to a torch to burn after standard-reach detection. The method has advantages of simple process, small device, convenient operation, high purity of obtained trifluoromethane, no secondary pollution, small investment, low operation cost and safe usage.

A refrigerant composition useful as a substitute for chlorodifluoromethane (CHClF2, HCFC-22). The refrigerant composition has a first constituent of difluoromethane (CH2F2, HFC-32); a second constituent of 1,1,1-trifluoroethane (CH3CF3; namely, HFC-143a); and a third constituent selected from cyclopropane (C3H6, RC-270), 1,1,1,2,3,3,3-heptafluoropropane (CF3CHFCF3, HFC-227ea), 1,1,1,2,2-pentafluoropropane (CH3CF2CF3, HFC-245cb), 1,1,1,2,3,3-hexafluoropropane (CHF2CHFCF3, HFC-236ea), butane (C4H10, R-600), bis(difluoromethyl)ether (CHF2OCHF2, HFE-134) and pentafluoroethylmethylether (CF3CF2OCH3, HFE-245).

An apparatus and method wherein potential ozone layer-damaging chlorodifluoromethane (Refrigerant R-22) is substituted with a mix of less environmentally damaging refrigerants pentafluoroethane and tetrafluoroethane in chlorodifluoromethane-based air-cooling systems for low temperature applications. While less environmentally damaging than chlorodifluoromethane, the substitute refrigerant has a temperature-pressure relationship similar to that of chlorodifluoromethane, making the substitute refrigerant suitable for use with chlorodifluoromethane-based low temperature systems. In this event, it is mixed with a relatively small percentage of a lubricating oil which is compatible with both the unit refrigerant and typical R-22 system design.