Patent ID: 8597471

Claim:
A method of concentrating contaminated sorbate in a solution comprising contaminated sorbate and clean sorbate wherein said contaminated sorbate has a freezing point and said clean sorbate has a freezing point and wherein the freezing point of said contaminated sorbate is higher than the freezing point of said clean sorbate, said method comprising the steps of: (a) cooling the solution to a temperature below the freezing point of the contaminated sorbate and above the freezing point of the clean sorbate; (b) repeating a sorbent/sorbate working pair adsorption/desorption cycle, said adsorption/desorption cycle comprising the steps of: (i) evaporating sorbate vapor from the solution; (ii) adsorbing sorbate vapor into a sorbent which can be regenerated; (iii) desorbing sorbate vapor from said sorbent; (iv) determining whether the sorbate vapor being processed during each repetition of the adsorption/desorption cycle may contain contaminated sorbate; (v) directing the sorbate vapor to either: (A) a clean condenser for condensing if the determination for the present adsorption/desorption cycle indicates that the sorbate vapor is clean sorbate vapor; or (B) a contaminated condenser for condensing if the determination for the present adsorption/desorption cycle indicates that the sorbate vapor may contain contaminated sorbate vapor; (vi) removing the clean sorbate condensed in the clean condenser; and (vii) returning the contaminated sorbate condensed in the contaminated condenser to the solution.