Fluorinated crown ethers and methods and systems for extraction of lithium using same

A method for removing lithium ions from an aqueous solution comprising lithium ions comprising:

• contacting the aqueous solution comprising lithium ions with one or more fluorinated crown ether(s) having the following structure:
• wherein R is an exocyclic fluorinated group and s is 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 and the exocyclic fluorinated group comprises a terminal fluorinated group, wherein
• the terminal fluorinated group is independently at each occurrence
• or
• wherein n is, independently at each occurrence, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20;
• m is, independently at each occurrence, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20;
• a, b, c, d, are, independently at each occurrence, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20;
• and A is, independently at each occurrence, H or F, and
• contacting the aqueous solution with a cation exchanger, and
• separating the aqueous solution that has been contacted with the one or more fluorinated crown ether(s) and the cation exchanger resulting in removal of at least a portion of or all of the lithium ions from the aqueous solution.