Azeotrope-like compositions and their use

An azeotrope-like composition including (a) perfluorobutyl ethyl ether, which ether consists essentially of about 95 weight percent perfluoro-n-butyl ethyl ether, and about 5 weight percent perfluoroisobutyl ethyl ether, and (b) organic solvent, wherein the composition is selected from the group consisting of:

• (i) compositions consisting essentially the ether and 1-chlorobutane, the compositions, when fractionally distilled, form a distillate fraction that is an azeotrope that consists essentially of about 74 weight percent of the ether and about 26 percent of the 1-chlorobutane and boils at about 69.degree. C. at about 730 torr;
• (ii) compositions consisting essentially of the ether and 1,2-dichloropropane, the compositions, when fractionally distilled, form a distillate fraction that is an azeotrope that consists essentially of about 84 weight percent of the ether and about 16 percent of the 1,2-dichloropropane and boils at about 74.degree. C. at about 730 torr;
• (iii) compositions consisting essentially of the ether and 2,2-dichloropropane, the compositions, when fractionally distilled, form a distillate fraction that is an azeotrope that consists essentially of about 55 weight percent of the ether and about 45 percent of the 2,2-dichloropropane and boils at about 66.degree. C. at about 729 torr;
• (iv) compositions consisting essentially of the ether and trans- 1,2-dichloroethylene, the compositions, when fractionally distilled, form a distillate fraction that is an azeotrope that consists essentially of about 37 weight percent of the ether and about 63 percent of the trans-1,2-dichloroethylene and boils at about 46.degree. C. at about 731 torr;
• and
• (v) compositions consisting essentially of the ether and 2,3-dichloro-1-propene, the compositions, when fractionally distilled, form a distillate fraction that is an azeotrope that consists essentially of about 82 weight percent of the ether and about 18 percent of the 2,3-dichloro-1-propene and boils at about 73.degree. C. at about 725 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 about ten percent.

An azeotrope-like composition including (a) perfluorobutyl methyl ether, wherein the ether consists essentially of about 18 weight percent perfluoro-n-butyl ethyl ether, and about 82 weight percent perfluoroisobutyl ethyl ether, and (b) organic solvent, wherein the composition is selected from the group consisting of:

• (i) compositions consisting essentially of the ether and 1-chlorobutane, the compositions, when fractionally distilled, form a distillate fraction that is an azeotrope that consists essentially of about 72 weight percent of the ether and about 28 percent of the 1-chlorobutane and boils at about 69.degree. C. at about 740 torr;
• (ii) compositions consisting essentially of the ether and 1,2-dichloropropane, the compositions, when fractionally distilled, form a distillate fraction that is an azeotrope that consists essentially of about 87 weight percent of the ether and about 13 percent of the 1,2-dichloropropane and boils at about 73.degree. C. at about 732 torr;
• (iii) compositions consisting essentially of the ether and 2,2-dichloropropane, the compositions, when fractionally distilled, form a distillate fraction that is an azeotrope that consists essentially of about 62 weight percent of the ether and about 38 percent of the 2,2-dichloropropane and boils at about 65.degree. C. at about 740 torr;
• (iv) compositions consisting essentially of the ether and trans-1,2-dichloroethylene, the compositions, when fractionally distilled, form a distillate fraction that is an azeotrope that consists essentially of about 31 weight percent of the ether and about 69 percent of the trans- 1,2-dichloroethylene and boils at about 45.degree. C. at about 731 torr;
• and
• (v) compositions consisting essentially of the ether and 1-bromopropane, the compositions, when fractionally distilled, form a distillate fraction that is an azeotrope that consists essentially of about 56 weight percent of the ether and about 44 percent of the 1-bromopropane and boils at about 63.degree. C. at about 730 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 about ten percent.