Metrohm 940 Vario - Sulfate in ICE column
Posted: Thu Jun 08, 2023 4:29 pm
Hello All,
I am in the process of qualifying a new instrument, a Metrohm 940 Vario IC with a 858 sample processor. The material to be analyzed using this instrument will primarily be hydrofluoric acid (about 50% strength HF but diluted during sample prep).
The issue I am running into is we utilize a Dionex ICE AS6 column to prevent fluoride overloading. The anions of interest here are chloride, nitrate, phosphate, and sulfate. We expected that the AS6 based on its material and storage before use to have to flush out some sulfate. Discussing with our Metrohm reps they suggested just running several water blanks to rinse it out (18.2 megaohm).
I've done this and based on the chromatograms, the sulfate peak doesn't seem to diminish.
Are there other suggestions in flushing out this sulfate? The AS6 is brand new.
Other details:
500 mM H2SO4 suppressor
Eluent is 3.2 mM Na2CO3, 1.0 mM NaHCO3
water reservoir and dosino reservoir uses 18.2 DI water.
thanks in advance.
I am in the process of qualifying a new instrument, a Metrohm 940 Vario IC with a 858 sample processor. The material to be analyzed using this instrument will primarily be hydrofluoric acid (about 50% strength HF but diluted during sample prep).
The issue I am running into is we utilize a Dionex ICE AS6 column to prevent fluoride overloading. The anions of interest here are chloride, nitrate, phosphate, and sulfate. We expected that the AS6 based on its material and storage before use to have to flush out some sulfate. Discussing with our Metrohm reps they suggested just running several water blanks to rinse it out (18.2 megaohm).
I've done this and based on the chromatograms, the sulfate peak doesn't seem to diminish.
Are there other suggestions in flushing out this sulfate? The AS6 is brand new.
Other details:
500 mM H2SO4 suppressor
Eluent is 3.2 mM Na2CO3, 1.0 mM NaHCO3
water reservoir and dosino reservoir uses 18.2 DI water.
thanks in advance.