Azeotrope-like compositions and their use

An azeotrope-like composition including perfluorobutyl methyl ether, wherein said ether consists essentially of:

• (a) about 35 weight percent perfluoro-n-butyl methyl ether, and about 65 weight percent perfluoroisobutyl methyl ether, and (b) organic solvent, which composition is selected from the group consisting of:
• (i) compositions consisting essentially of the ether and methanol, the compositions, when fractionally distilled, form a distillate fraction that is an azeotrope that consists essentially of about 90 weight percent of the ether and 10 percent of the methanol and boils at about 46.degree. C. at about 733 torr;
• (ii) compositions consisting essentially of the ether and ethanol, the compositions, when fractionally distilled, form a distillate fraction that is an azeotrope that consists essentially of about 93 weight percent of the ether and about 7 percent of the ethanol and boils at about 52.degree. C. at about 732 torr;
• (iii) compositions consisting essentially of the ether and 1-propanol, the compositions, when fractionally distilled, form a distillate fraction that is an azeotrope that consists essentially of about 97 weight percent of the ether and about 3 percent of the 1-propanol and boils at about 56.degree. C. at about 729 torr;
• (iv) compositions consisting essentially of the ether and 2-butanol, the compositions, when fractionally distilled, form a distillate fraction that is an azeotrope that consists essentially of about 98 weight percent of the ether and about 2 percent of the 2-butanol and boils at about 58.degree. C. at about 742 torr;
• (v) compositions consisting essentially of the ether and i-butanol, the compositions, when fractionally distilled, form a distillate fraction that is an azeotrope that consists essentially of about 99 weight percent of the ether and about 1 percent of the i-butanol and boils at about 58.degree. C. at about 742 torr;
• (vi) compositions consisting essentially of the ether and t-butanol, the compositions, when fractionally distilled, form a distillate fraction that is an azeotrope that consists essentially of about 94 weight percent of the ether and about 6 percent of the t-butanol and boils at about 56.degree. C. at about 741 torr;
• (vii) composition consisting essentially of the ether and 2-propanol which, when fractionally distilled, form a distillate fraction that is an azeotrope that consists essentially of about 93 weight percent of the ether and about 7 weight percent of the 2-propanol and boils at about 54.degree. C. at about 731 torr;
• wherein the concentrations of the ether and the organic solvent in the azeotrope-like composition differ from the concentrations of such components in the corresponding azeotrope by no more than ten percent.

An azeotrope-like composition including perfluorobutyl methyl ether, wherein the ether consists essentially of about 65 weight percent perfluoroisobutyl methyl ether and about 35 weight percent perfluoro-n-butyl methyl ether, and two or more organic solvents, and the azeotrope-like composition is selected from the group consisting of:

• (i) compositions consisting essentially of the ether, trans-1,2-dichloroethylene and methanol, which when fractionally distilled, produces a distillate fraction that is an azeotrope consisting essentially of about 51.9 weight percent of the ether, and about 43.0 weight percent of the trans-1,2-dichloroethylene and about 5.1 weight percent of the methanol, the azeotrope boiling at about 36.degree. C. at about 732 torr;
• (ii) compositions consisting essentially of the ether, trans-1,2-dichloroethylene and ethanol which, when fractionally distilled, produce a distillate fraction that is an azeotrope consisting essentially of about 52.7 weight percent of the ether and about 44.6 weight percent of the trans-1,2-dichloroethylene and about 2.7 weight percent of the ethanol, the azeotrope boiling at about 40.degree. C. at about 731 torr;
• (iii) compositions consisting essentially of the ether, trans-1,2-dichloroethylene and about 1-propanol which, when fractionally distilled, produce a distillate fraction that is an azeotrope consisting essentially of about 51.1 weight percent of the ether, about 48.6 weight percent of the trans-1,2-dichloroethylene and about 0.3 weight percent of the 1-propanol, the azeotrope boiling at about 40.degree. C. at about 733 torr;
• (iv) compositions consisting essentially of the ether, trans-1,2-dichloroethylene and 2-propanol which, when fractionally distilled, produce a distillate fraction that is an azeotrope consisting essentially of about 51.7 weight percent of the ether, about 47.0 weight percent of the trans-1,2-dichloroethylene and about 1.3 weight percent of the 2-propanol, the azeotrope boiling at about 40.degree. C. at about 737 torr;
• (v) compositions consisting essentially of the ether, trans-1,2-dichloroethylene and t-butanol which, when fractionally distilled, produce a distillate fraction that is an azeotrope consisting essentially of about 53.5 weight percent of the ether, about 45.9 weight percent of the trans-1,2-dichloroethylene and about 0.6 weight percent of the t-butanol, the azeotrope boiling at about 40.degree. C. at about 730 torr;
• (vi) compositions consisting essentially of the ether, HCFC-225 ca/cb and methanol which, when fractionally distilled, produce a distillate fraction that is an azeotrope consisting essentially of about 45.6 weight percent of the ether, about 48.6 weight percent of the HCFC-225 ca/cb and about 6.6 weight percent of the methanol, the azeotrope boiling at about 46.degree. C. at about 734 torr;
• and
• (vii) compositions consisting essentially of the ether, HCFC-225 ca/cb and ethanol, which when fractionally distilled, produces a distillate fraction that is an azeotrope consisting essentially of about 42.5 weight percent of the ether, about 53.2 weight percent of the HCFC-225 ca/cb about 4.3 weight percent of the ethanol, the azeotrope boiling at about 51.degree. C. at about 735 torr;
• wherein the concentrations of the ether and the organic solvents in the azeotrope-like composition differ from the concentrations of such components in the corresponding azeotrope by no more than ten percent.