I'm writing about the treatment of methane gas, and in one part of the process, the methane gas is dried in a tank called a scrubber. Here, a desiccant called triethylene glycol is used.
Thinking about another desiccant, magnesium sulfate heptahydrate (Epsom salt), the water must be taken away through evaporation before the salt can be used for drying. The chemical must be anhydrous, so that it'll steal away all the water from the object in need of drying.
However, is this the case with triethylene glycol? Must it be made anhydrous before it can be used for drying, or is its attraction to water molecules great enough to begin with?