# US 11,028,300 B1 · Environmentally friendly refrigerant compositions > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,028,300 B1 - Document ID: US11028300B1 - Status: Granted - Kind: B1 - Application number: 17/023,045 - Filed: 2020-09-16 - Granted: 2021-06-08 - Earliest claimed: 2020-09-16 - Applicants: David L. Couchot; Sankara N. Ramanan - Inventors: David L. Couchot; Sankara N. Ramanan - Web page: https://patentgrep.com/patent/US11028300B1 ## CPC - C09K 5/045: {containing only fluorine as halogen} - C09K 5/042: {comprising compounds containing carbon and hydrogen only} - C09K 2205/122: Halogenated hydrocarbons - C09K 2205/40: Replacement mixtures - C09K: MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE ## Abstract A refrigerant composition includes R125 (pentafluoroethane), R134a (1,1,1,2-tetrafluoroethane), R600a (isobutane) and a polyol ester (POE) lubricant. In one exemplary embodiment, the refrigerant includes about 53-57 wt % R125, about 40-44 wt % R134a, about 1-5 wt % R600a and no more than about 1 wt % POE. In another embodiment, the refrigerant composition includes about 54-56% R125, about 41-43 wt % R134a, about 2-4% R600a and about 0.3-0.7 wt % POE. In yet another embodiment, the refrigerant composition includes about 54.63 wt % R125, about 41.72 wt % R134a, about 2.98 wt % R600a and about 0.67 wt % POE. Manufacturing the refrigerant composition includes charging a vessel with about 53-57 wt % R125, about 44 wt % R134a, about 1-5 wt % R600a to form as 100 wt % charge, and then injecting no more than about 1 wt % POE. ## Claims ### Claim 1 A refrigerant composition, comprising: about 53-56 wt. % pentafluoroethane; about 40-44 wt % 1,1,1,2-tetrafluoroethane; about 1-5 wt % isobutane; and 0.3-0.7 wt % polyol ester. ### Claim 2 (depends on 1) The refrigerant composition of claim 1, wherein the refrigerant composition comprises: about 54-56 wt. % pentafluoroethane; about 41-43 wt % 1,1,1,2-tetrafluoroethane; and about 2-4 wt % isobutane. ### Claim 3 (depends on 1) The refrigerant composition of claim 1, wherein the refrigerant composition comprises: about 54.6 wt. % pentafluoroethane; about 41.7 wt % 1,1,1,2-tetrafluoroethane; about 3.0 wt % isobutane; and about 0.7 wt % polyol ester. ### Claim 4 (depends on 1) The refrigerant composition of claim 1, wherein the refrigerant composition comprises: about 54.63 wt. % pentafluoroethane; about 41.72 wt % 1,1,1,2-tetrafluoroethane; about 2.98 wt % isobutane; and about 0.67 wt % polyol ester. ### Claim 5 (depends on 1) The refrigerant composition of claim 1, wherein the polyol ester has a viscosity of about 32.5 cSt at 40° C. and about 5.8 cSt at 100° C. ### Claim 6 (depends on 1) The refrigerant composition of claim 1, wherein the polyol ester has a pour point of about −46° C. and a density of about 0.98 g/ml at 20° C. ### Claim 7 (depends on 1) The refrigerant composition of claim 1, wherein the refrigerant composition has a global warming potential of about 2525 compared to carbon dioxide. ### Claim 8 (depends on 1) The refrigerant composition of claim 1, wherein the refrigerant composition has a theoretical boiling point of about −37.9° C. ### Claim 9 (depends on 1) The refrigerant composition of claim 1, wherein the refrigerant composition further comprises at least one additive selected from the group consisting of oxidation resistance and thermal stability enhancers, corrosion inhibitors, metal deactivators, lubricity additives, viscosity index enhancers, pour and/or floc point depressants, detergents, dispersants, antifoaming agents, anti-wear agents, and extreme pressure resistant additives. ### Claim 10 A method for manufacturing a refrigerant composition, the method comprising: charging a vessel with a refrigerant composition having: about 55 wt % pentafluoroethane, about 42 wt % 1,1,1,2-tetrafluoroethane, and about 3% isobutane for a 100% charge; and injecting into the vessel 0.3-0.7 wt % polyol ester, based on the 100% charge. ### Claim 11 (depends on 10) The method of claim 10, wherein the polyol ester has a pour point of about −46° C., and a density of about 0.98 g/ml at 20° C. ### Claim 12 (depends on 10) The method of claim 10, wherein the refrigerant composition has a global warming potential of about 2525 compared to carbon dioxide. ### Claim 13 (depends on 10) The method of claim 10, wherein the refrigerant composition has a theoretical boiling point of about −37.9° C. ### Claim 14 (depends on 10) The method of claim 10, wherein the refrigerant composition further comprises at least one additive selected from the group consisting of oxidation resistance and thermal stability enhancers, corrosion inhibitors, metal deactivators, lubricity additives, viscosity index enhancers, pour and/or floc point depressants, detergents, dispersants, antifoaming agents, anti-wear agents, and extreme pressure resistant additives. ### Claim 15 A method for filling an apparatus designed for use with a chlorodifluoromethane refrigerant, the method comprising: selecting a substitute refrigerant composition comprising about 53-57 wt % pentafluoroethane, about 40-44 wt % 1,1,1,2-tetrafluoroethane, about 1-5 wt % isobutane, and 0.3-0.7 wt % polyol ester; supplying the substitute refrigerant composition under pressure in a cylinder fitted with an outlet compatible with a chlorodifluoromethane recharging manifold of the apparatus; and adding to the apparatus the substitute refrigerant composition. ### Claim 16 (depends on 15) The method of claim 15, wherein the polyol ester has a pour point of about −46° C. and a density of about 0.977 g/ml at 20° C. ### Claim 17 (depends on 15) The method of claim 15, wherein the refrigerant composition has a vapor pressure of about 136.4 psi at 21° C. and a theoretical boiling point of about −37.9° C. ### Claim 18 (depends on 15) The method of claim 15, wherein the refrigerant composition further comprises at least one additive selected from the group consisting of oxidation resistance and thermal stability enhancers, corrosion inhibitors, metal deactivators, lubricity additives, viscosity index enhancers, pour and/or floc point depressants, detergents, dispersants, antifoaming agents, anti-wear agents, and extreme pressure resistant additives.