Ammonium bitartrate is even more insoluble than cesium bitartrate:
https://en.wikipedia.org/wiki/Solubility_table
(1.88% at 10 C and 2.7% at 20 C)
In general bitartrate salts of monovalent ions are very insoluble, although sodium is (usually!) the exception. I believe lithium bitartrate also has
high solubility. Zinc forms double salts; magnesium inhibits the deposition of tartrates. Quite simply, the ion is a jerk.
Hexamethonium bitartrate on the other hand has a very high solubility because it is a double quaternary ammonium salt which cannot form a tightly
bonded crystal structure with bitartrate ions.
It's possible that lysine or arginine could be used as the base, though, since their bitartrates should be quite soluble. It should be possible to
obtain these. But I still think sodium bitartrate can work pretty well as long as you're careful with the stoichiometry.
Calcium nitrate might also work, since cesium nitrate has roughly the same solubility as cesium bitartrate, whereas Ca(NO3)2 is extremely soluble.
[Edited on 1-11-2017 by clearly_not_atara] |