The present invention relates to a method for preparing 2-methylallyl chloride from 1,2-dichloro-tert-butane. The method is characterized in that 1,2-dichloro-tert-butane and a sodium hydroxide aqueous solution are used as raw materials; reactive rectification is performed in a combined rectifying tower to eliminate hydrogen chloride so as to obtain 2-methylallyl chloride. A plate type tower is provided at the lower part of the combined rectifying tower; a packing tower is provided at the upper part of the combined rectifying tower; an inner reflux condenser is provided at the top of the combined rectifying tower. The sodium hydroxide aqueous solution is added from a first plate of the plate type tower; and 1,2-dichloro-tert-butane is added from the middle part of the plate type tower. The method has the advantages that the raw material 1 and 1,2-dichloro-tert-butane is fully converted; the selectivity of the 2-methylallyl chloride is high.

The present invention relates to a method for preparing 2-methylallyl chloride from 1,2-dichloro-tert-butane. The method is characterized in that 1,2-dichloro-tert-butane and a sodium hydroxide aqueous solution are used as raw materials; reactive rectification is performed in a combined rectifying tower to eliminate hydrogen chloride so as to obtain 2-methylallyl chloride. A plate type tower is provided at the lower part of the combined rectifying tower; a packing tower is provided at the upper part of the combined rectifying tower; an inner reflux condenser is provided at the top of the combined rectifying tower. The sodium hydroxide aqueous solution is added from a first plate of the plate type tower; and 1,2-dichloro-tert-butane is added from the middle part of the plate type tower. The method has the advantages that the raw material 1 and 1,2-dichloro-tert-butane is fully converted; the selectivity of the 2-methylallyl chloride is high.

The present invention relates to a method for preparing 2-methylallyl chloride from 1,2-dichloro-tert-butane. The method is characterized in that 1,2-dichloro-tert-butane and a sodium hydroxide aqueous solution are used as raw materials; reactive rectification is performed in a combined rectifying tower to eliminate hydrogen chloride so as to obtain 2-methylallyl chloride. A plate type tower is provided at the lower part of the combined rectifying tower; a packing tower is provided at the upper part of the combined rectifying tower; an inner reflux condenser is provided at the top of the combined rectifying tower. The sodium hydroxide aqueous solution is added from a first plate of the plate type tower; and 1,2-dichloro-tert-butane is added from the middle part of the plate type tower. The method has the advantages that the raw material 1 and 1,2-dichloro-tert-butane is fully converted; the selectivity of the 2-methylallyl chloride is high.

The present invention relates to a process for purifying olefin feed comprising R-5 1234yf, R-40, R-134a, R-134, R-1225zc, and OFCB, comprising the step of separating different ternary and binary azeotrope compositions comprising 1234yf. The olefin feed is obtained from the pyrolysis of tetrafluoroethylene/chlorodifluoromethane with chloromethane/methane, optionally in presence of initiator.

The present invention relates to a process for purifying olefin feed comprising R-5 1234yf, R-40, R-134a, R-134, R-1225zc, and OFCB, comprising the step of separating different ternary and binary azeotrope compositions comprising 1234yf. The olefin feed is obtained from the pyrolysis of tetrafluoroethylene/chlorodifluoromethane with chloromethane/methane, optionally in presence of initiator.

The present invention relates to a process for purifying olefin feed comprising R-5 1234yf, R-40, R-134a, R-134, R-1225zc, and OFCB, comprising the step of separating different ternary and binary azeotrope compositions comprising 1234yf. The olefin feed is obtained from the pyrolysis of tetrafluoroethylene/chlorodifluoromethane with chloromethane/methane, optionally in presence of initiator.

Aspects of the invention relate to systems and processes for recovering R1233zd in purified form from compositions additionally comprising hydrogen fluoride. In accordance with one aspect, the invention provides a process that includes separating a feed stream comprised of hydrogen fluoride and R1233zd using azeotropic distillation in a first distillation column to produce a first distillate stream comprised of hydrogen fluoride and R1233zd and a first bottoms stream consisting essentially of hydrogen fluoride. The first distillation column is operated at a first pressure. The process further includes separating the first distillate stream using azeotropic distillation in a second distillation column to produce a second distillate stream comprised of hydrogen fluoride and R1233zd and a second bottoms stream consisting essentially of R1233zd. The second distillation column is operated at a second pressure that may be different than the first pressure of the first distillation column.

Aspects of the invention relate to systems and processes for recovering R1233zd in purified form from compositions additionally comprising hydrogen fluoride. In accordance with one aspect, the invention provides a process that includes separating a feed stream comprised of hydrogen fluoride and R1233zd using azeotropic distillation in a first distillation column to produce a first distillate stream comprised of hydrogen fluoride and R1233zd and a first bottoms stream consisting essentially of hydrogen fluoride. The first distillation column is operated at a first pressure. The process further includes separating the first distillate stream using azeotropic distillation in a second distillation column to produce a second distillate stream comprised of hydrogen fluoride and R1233zd and a second bottoms stream consisting essentially of R1233zd. The second distillation column is operated at a second pressure that may be different than the first pressure of the first distillation column.

Aspects of the invention relate to systems and processes for recovering R1233zd in purified form from compositions additionally comprising hydrogen fluoride. In accordance with one aspect, the invention provides a process that includes separating a feed stream comprised of hydrogen fluoride and R1233zd using azeotropic distillation in a first distillation column to produce a first distillate stream comprised of hydrogen fluoride and R1233zd and a first bottoms stream consisting essentially of hydrogen fluoride. The first distillation column is operated at a first pressure. The process further includes separating the first distillate stream using azeotropic distillation in a second distillation column to produce a second distillate stream comprised of hydrogen fluoride and R1233zd and a second bottoms stream consisting essentially of R1233zd. The second distillation column is operated at a second pressure that may be different than the first pressure of the first distillation column.

The present disclosure provides azeotrope or azeotrope-like compositions including trifluoroiodomethane (CF.sub.3I) and trifluoroacetyl chloride (CF.sub.3COCl), and a method of forming an azeotrope or azeotrope-like composition comprising the step of combining trifluoroacetyl chloride (CF.sub.3COCl) and trifluoroiodomethane (CF.sub.3I) to form an azeotrope or azeotrope-like composition.