A method for extracting a rare earth element from a rare earth-containing substance, the method comprising mixing the rare earth-containing substance with a protic ionic liquid, such as:

##STR00001##

wherein R.sup.1 is selected from hydrogen atom and hydrocarbon groups containing 1 to 6 carbon atoms; R.sup.2 and R.sup.3 are independently selected from hydrocarbon groups containing 1 to 12 carbon atoms; and X.sup.− is an anionic species; to produce a composition of the formula (RE)(amide).sub.yX.sub.z at least partially dissolved in the protic ionic liquid, wherein RE is at least one rare earth element having an atomic number selected from 39, 57-71, and 90-103; y is 2-6; z is a number that charge balances the total positive charge of RE; and the amide is the conjugate base of the cationic portion of the protic ionic liquid of Formula (1) and has the following formula:

##STR00002##

A method for extracting a rare earth element from a rare earth-containing substance, the method comprising mixing the rare earth-containing substance with a protic ionic liquid, such as: ##STR00001##
wherein R.sup.1 is selected from hydrogen atom and hydrocarbon groups containing 1 to 6 carbon atoms; R.sup.2 and R.sup.3 are independently selected from hydrocarbon groups containing 1 to 12 carbon atoms; and X.sup.− is an anionic species; to produce a composition of the formula (RE)(amide).sub.yX.sub.z at least partially dissolved in the protic ionic liquid, wherein RE is at least one rare earth element having an atomic number selected from 39, 57-71, and 90-103; y is 2-6; z is a number that charge balances the total positive charge of RE; and the amide is the conjugate base of the cationic portion of the protic ionic liquid of Formula (1) and has the following formula: ##STR00002##

A method for extracting a rare earth element from a rare earth-containing substance, the method comprising mixing the rare earth-containing substance with a protic ionic liquid, such as:

##STR00001##

wherein R.sup.1 is selected from hydrogen atom and hydrocarbon groups containing 1 to 6 carbon atoms; R.sup.2 and R.sup.3 are independently selected from hydrocarbon groups containing 1 to 12 carbon atoms; and X.sup. is an anionic species; to produce a composition of the formula (RE)(amide).sub.yX.sub.z at least partially dissolved in the protic ionic liquid, wherein RE is at least one rare earth element having an atomic number selected from 39, 57-71, and 90-103; y is 2-6; z is a number that charge balances the total positive charge of RE; and the amide is the conjugate base of the cationic portion of the protic ionic liquid of Formula (1) and has the following formula:

##STR00002##

A method for extracting a rare earth element from a rare earth-containing substance, the method comprising mixing the rare earth-containing substance with a protic ionic liquid, such as: ##STR00001##
wherein R.sup.1 is selected from hydrogen atom and hydrocarbon groups containing 1 to 6 carbon atoms; R.sup.2 and R.sup.3 are independently selected from hydrocarbon groups containing 1 to 12 carbon atoms; and X.sup. is an anionic species; to produce a composition of the formula (RE)(amide).sub.yX.sub.z at least partially dissolved in the protic ionic liquid, wherein RE is at least one rare earth element having an atomic number selected from 39, 57-71, and 90-103; y is 2-6; z is a number that charge balances the total positive charge of RE; and the amide is the conjugate base of the cationic portion of the protic ionic liquid of Formula (1) and has the following formula: ##STR00002##

Provided is a method for efficiently separating and recovering tungsten and other valuable(s) from at least one valuable containing tungsten. The present invention relates to a method for recovering at least one valuable containing tungsten, comprising subjecting a raw material mixture comprising at least one valuable containing tungsten to electrolysis using an electrolytic solution containing at least one alcohol amine to dissolve tungsten in the electrolytic solution, electrodeposit a part of the valuable(s) onto a cathode used for the electrolysis and separate at least one valuable other than the valuable(s) electrodeposited onto the cathode as a residue in the electrolytic solution, and then separating and recovering each of the residue and the valuable(s) electrodeposited onto the cathode.

Provided is a method for efficiently separating and recovering tungsten and other valuable(s) from at least one valuable containing tungsten. The present invention relates to a method for recovering at least one valuable containing tungsten, comprising subjecting a raw material mixture comprising at least one valuable containing tungsten to electrolysis using an electrolytic solution containing at least one alcohol amine to dissolve tungsten in the electrolytic solution, electrodeposit a part of the valuable(s) onto a cathode used for the electrolysis and separate at least one valuable other than the valuable(s) electrodeposited onto the cathode as a residue in the electrolytic solution, and then separating and recovering each of the residue and the valuable(s) electrodeposited onto the cathode.