A method for recovering raw and auxiliary materials in the production of lithium bis(fluorosulfonyl)imide is described. The method includes one or more different recovery sections A, B, C, D and/or E, corresponding to the recovery and post-treatment of the raw and auxiliary materials such as triethylamine, a fluoride ion, an ester solvent, and a crystallization liquid respectively used in the production of lithium bis(fluorosulfonyl)imide. The method for recovering raw and auxiliary materials of the present application enables the production of lithium bis(fluorosulfonyl)imide to have significantly improved economic efficiency and environmental protection.

A method for recovering raw and auxiliary materials in the production of lithium bis(fluorosulfonyl)imide is described. The method includes one or more different recovery sections A, B, C, D and/or E, corresponding to the recovery and post-treatment of the raw and auxiliary materials such as triethylamine, a fluoride ion, an ester solvent, and a crystallization liquid respectively used in the production of lithium bis(fluorosulfonyl)imide. The method for recovering raw and auxiliary materials of the present application enables the production of lithium bis(fluorosulfonyl)imide to have significantly improved economic efficiency and environmental protection.

Provided is an industrially simple and cheap method for efficiently removing butene from crude monofluorobutane containing butene without causing substantial decomposition, transformation, or the like of the monofluorobutane. In a provided monofluorobutane purification method, crude monofluorobutane containing butene is brought into contact with trihalomethane in the presence of an alkali aqueous solution to convert the butene to a compound having a higher boiling point than the monofluorobutane, water is subsequently added to a reaction mixture obtained thereby to dissolve a produced salt, an organic layer is separated, and then the separated organic layer is purified by distillation.

Provided is an industrially simple and cheap method for efficiently removing butene from crude monofluorobutane containing butene without causing substantial decomposition, transformation, or the like of the monofluorobutane. In a provided monofluorobutane purification method, crude monofluorobutane containing butene is brought into contact with trihalomethane in the presence of an alkali aqueous solution to convert the butene to a compound having a higher boiling point than the monofluorobutane, water is subsequently added to a reaction mixture obtained thereby to dissolve a produced salt, an organic layer is separated, and then the separated organic layer is purified by distillation.

Benzene and/or monochlorobenzene were chlorinated with molecular chlorine to obtain paradichlorobenzene with high selectivity. A batch reactor was used for this purpose, with a highly selective catalytic system consisting of SbCl.sub.3 and a phenothiazine derivative. The entire process was improved with the introduction of a new catalytic system recovery method, which was based on returning the mother liquid containing the catalytic system to the process after prior separation from the fresh post-reaction mixture by distillation of unreacted raw materials under reduced pressure and recycling them, as well as crystallization of paradichlorobenzene from the depleted liquid after vacuum distillation.

Benzene and/or monochlorobenzene were chlorinated with molecular chlorine to obtain paradichlorobenzene with high selectivity. A batch reactor was used for this purpose, with a highly selective catalytic system consisting of SbCl.sub.3 and a phenothiazine derivative. The entire process was improved with the introduction of a new catalytic system recovery method, which was based on returning the mother liquid containing the catalytic system to the process after prior separation from the fresh post-reaction mixture by distillation of unreacted raw materials under reduced pressure and recycling them, as well as crystallization of paradichlorobenzene from the depleted liquid after vacuum distillation.

Provided is an industrially simple and cheap method for efficiently removing butene from crude monofluorobutane containing butene without causing substantial decomposition, transformation, or the like of the monofluorobutane. In a provided monofluorobutane purification method, crude monofluorobutane containing butene is brought into contact with trihalomethane in the presence of an alkali aqueous solution to convert the butene to a compound having a higher boiling point than the monofluorobutane, water is subsequently added to a reaction mixture obtained thereby to dissolve a produced salt, an organic layer is separated, and then the separated organic layer is purified by distillation.

Provided is an industrially simple and cheap method for efficiently removing butene from crude monofluorobutane containing butene without causing substantial decomposition, transformation, or the like of the monofluorobutane. In a provided monofluorobutane purification method, crude monofluorobutane containing butene is brought into contact with trihalomethane in the presence of an alkali aqueous solution to convert the butene to a compound having a higher boiling point than the monofluorobutane, water is subsequently added to a reaction mixture obtained thereby to dissolve a produced salt, an organic layer is separated, and then the separated organic layer is purified by distillation.