A method for preparing aluminum fluoride and aluminum oxide by decarburization and sodium removal of an aluminum electrolysis carbon residue is disclosed. The method includes: crushing the aluminum electrolysis carbon residue into fine particles not larger than 3 mm, adding decarburization agent into the carbon residue, mixing to obtain first mixture, adding the first mixture into a high-temperature furnace, conducting I-stage heating treatment in air atmosphere to obtain crude fluoride salt A; adding sodium removal agent into the crude fluoride salt A, mixing to obtain second mixture, adding the second mixture into high-temperature furnace, and conducting

II-stage heating treatment to obtain crude fluoride salt B; adding the crude fluoride salt B into stirring tank, adding industrial pure water, dissolving a sodium salt into water, and conducting solid-liquid separation to obtain precipitate C and sodium salt solution D; drying the precipitate C to obtain aluminum fluoride and aluminum oxide.

A method for preparing aluminum fluoride and aluminum oxide by decarburization and sodium removal of an aluminum electrolysis carbon residue is disclosed. The method includes: crushing the aluminum electrolysis carbon residue into fine particles not larger than 3 mm, adding decarburization agent into the carbon residue, mixing to obtain first mixture, adding the first mixture into a high-temperature furnace, conducting I-stage heating treatment in air atmosphere to obtain crude fluoride salt A; adding sodium removal agent into the crude fluoride salt A, mixing to obtain second mixture, adding the second mixture into high-temperature furnace, and conducting

II-stage heating treatment to obtain crude fluoride salt B; adding the crude fluoride salt B into stirring tank, adding industrial pure water, dissolving a sodium salt into water, and conducting solid-liquid separation to obtain precipitate C and sodium salt solution D; drying the precipitate C to obtain aluminum fluoride and aluminum oxide.

A method of treating a waste liquid includes: an aluminum dissolution step of dissolving aluminum in an acidic waste liquid and performing separation into a first treated water and a reduced heavy metal precipitate; a gypsum recovery step of adding a calcium compound to the first treated water at a liquid property of a pH of 4 or less, and performing separation into a second treated water and gypsum; an aluminum and fluorine removal step of adding an alkali to the second treated water and performing separation into a third treated water and a precipitate containing aluminum and fluorine; and a neutralization step of adding an alkali to the third treated water and performing separation into an alkali neutralization treated water and a neutralized precipitate of a heavy metal hydroxide.

A method of treating a waste liquid: an aluminum dissolution step of dissolving aluminum in an acidic waste liquid and performing separation into a first treated water and a reduced heavy metal precipitate; a gypsum recovery step of adding a calcium compound to the first treated water at a pH of 4 or less, and performing separation into a second treated water and gypsum; a heavy metal coprecipitation step of adding a ferric compound to the second treated water and performing separation into a third treated water and a heavy metal coprecipitate; an aluminum and fluorine removal step of adding an alkali to the third treated water and performing separation into a fourth treated water and a precipitate containing aluminum and fluorine; and a neutralization step of adding an alkali to the fourth treated water and performing separation into an alkali neutralization treated water and a neutralized heavy metal hydroxide.

Provided are: a negative electrode mixture composite which is for a fluoride ion secondary battery having high initial charge/discharge efficiency, and by which the fluoride ion secondary battery that starts charging can be achieved; a negative electrode and a secondary battery for a fluoride ion secondary battery using said composite; and a method for producing said composite. This composite is formed with other components of a negative electrode mixture, using, as negative electrode active materials, nanoparticle-sized aluminum and modified aluminum fluoride having vacancies due to the desorption of fluoride ions, and thus forming a coating due to aluminum fluoride formed by a refluorination reaction after defluorination is suppressed, and the aggregation of particles of negative electrode active materials is suppressed.

Provided are: a negative electrode mixture composite which is for a fluoride ion secondary battery having high initial charge/discharge efficiency, and by which the fluoride ion secondary battery that starts charging can be achieved; a negative electrode and a secondary battery for a fluoride ion secondary battery using said composite; and a method for producing said composite. This composite is formed with other components of a negative electrode mixture, using, as negative electrode active materials, nanoparticle-sized aluminum and modified aluminum fluoride having vacancies due to the desorption of fluoride ions, and thus forming a coating due to aluminum fluoride formed by a refluorination reaction after defluorination is suppressed, and the aggregation of particles of negative electrode active materials is suppressed.

A method for treating wastewater containing fluorine is disclosed. The method for treating wastewater includes applying a vacuum to a membrane unit including a membrane having a hollow, injecting wastewater into the membrane unit so that the wastewater contacts an outer surface of the membrane, recovering hydrofluoric acid gas by evaporating hydrofluoric acid (HF) in the wastewater based on a vacuum applied to the inner surface of the membrane and moving the evaporated hydrofluoric acid (HF) to the inner surface through the membrane, injecting sweep gas into the membrane unit to discharge hydrofluoric acid gas remaining on the inner surface of the membrane, and forming a metal fluoride by reacting the recovered hydrofluoric acid gas with a metal oxide or metal hydroxide using a scrubbing process.

A method for treating wastewater containing fluorine is disclosed. The method for treating wastewater includes applying a vacuum to a membrane unit including a membrane having a hollow, injecting wastewater into the membrane unit so that the wastewater contacts an outer surface of the membrane, recovering hydrofluoric acid gas by evaporating hydrofluoric acid (HF) in the wastewater based on a vacuum applied to the inner surface of the membrane and moving the evaporated hydrofluoric acid (HF) to the inner surface through the membrane, injecting sweep gas into the membrane unit to discharge hydrofluoric acid gas remaining on the inner surface of the membrane, and forming a metal fluoride by reacting the recovered hydrofluoric acid gas with a metal oxide or metal hydroxide using a scrubbing process.

The invention relates to the use of aryliodonium and/or arylsulfonium salts of the tetrakis(perfluoro-t-butyloxy)aluminate anion of the following formula (I): ##STR00001##
as cationic initiators cleavable by light and/or free radicals for polymerizing cationically polymerizable monomers.

The invention relates to the use of aryliodonium and/or arylsulfonium salts of the tetrakis(perfluoro-t-butyloxy)aluminate anion of the following formula (I): ##STR00001##
as cationic initiators cleavable by light and/or free radicals for polymerizing cationically polymerizable monomers.