Patent ID: 11905180
Assignee: TORAY INDUSTRIES, INC.
Field: Chemical engineering (Chemistry)
Classification: CPC B  C  H  Y | IPC B  C

Claim 24:
25. The method for recovering a rare metal salt according to claim 12, wherein
the reverse osmosis membrane used in the concentration step comprises a base material, a porous support layer on the base material, and a separation function layer on the porous support layer, and
the separation function layer comprises a crosslinked aromatic polyamide, and the crosslinked aromatic polyamide has at least one of structures represented by the following general formula (3) or (4),, provided that Ar1 to Ar3 are each independently an aromatic ring having 5 to 14 carbon atoms which may have a substituent, R1 is an atomic group having neither an aromatic ring nor a heteroatom, X is a hydrogen atom or a carboxy group, and R2 to R5 are each independently a hydrogen atom or an aliphatic chain having 1 to 10 carbon atoms.