Characterizing ionic and nonionic condensation from a mixed vapor stream

A method, comprising:

• (a) forming a mixed vapor supply stream at a first elevated temperature, wherein the mixed vapor supply stream includes a measured amount of water vapor, a measured amount of hydrocarbon vapor, and a carrier gas;
• and
• (b) for each of a plurality of target temperatures less than the first elevated temperature:
• (i) cooling the mixed vapor supply stream to a target temperature to form a first liquid stream and a mixed vapor outlet stream;
• (ii) cooling the mixed vapor outlet stream to condense vapor from the mixed vapor outlet stream to form a second liquid stream;
• (iii) measuring an amount of a selected component in the second liquid stream;
• and
• (iv) calculating an amount of the selected component in the first liquid stream as the difference between the measured amount of the selected component in the mixed vapor supply stream and the measured amount of the selected component in the second liquid stream;
• and
• (c) analyzing the amount of the selected component as a function of the target temperature to identify a lowest temperature at which the first liquid stream is expected to contain none of the selected component other than an amount soluble in the first liquid stream.