Hello, I am a student investigating acetate ions in wood.
My current mobile phase is 1000:0.5 (H2O;H2SO4) and I do not have the most resolute peak for acetate. The column is a H+ Column packed with sulfonated styrene /divinylbenzene copolymer backbone. What is a mobile phase worth trying?
pH mobile phase currently is ~2.0
pKA acetic acid is 4.76.
Analyt is acetate in NaOH with a basic pH.
Also is a buffer useful, if so which buffer is needed for acetate ions?
https://www.agilent.com/cs/library/primers/Public/5991-3326EN_SPHB.pdf
https://doi.org/10.3390/separations9060146
https://doi.org/10.1016/j.talanta.2007.11.025
https://doi.org/10.1016/j.jfca.2016.12.010
Hello,
Obviously you are working under conditions of ion-exclusion chromatography, which was quite popular for analysis of organic acids. Briefly, in IEC you need sulfonated ion-exchange column and diluted strong acid eluent. The preferred eluent is sulfuric or phosphoric acid as they are transparent and you can use UV-Vis detector for reliable detection of acetate at 210 nm.
Probably, your problem is connected with the presence of relatively concentrated alkali in your samples. If the concentration of alkali is too high the acetate will not be retained. In this case you can use classic ion-exchange chromatography using anion-exchange column and conductivity or UV-Vis detector.
It will be better to neutralise your sample with sulfuric acid, which is a component of your eluent. Of course, you can use a bit more concentrated acid than in the eluent.
- Badges
- Science topic