by
Khanom » Wed May 16, 2018 12:45 pm
Dear iperdomo,
I am sorry, but I was not able to visualise an image.
1 I am unaware of the type of waste water you are sampling. It is possible to clean up the matrix using solid phase extraction (SPE) prior to injection onto the IC system, or even dilute with IC grade water. Do you use a guard column?
2 You should be able to determine the lower concentrations of say 1 mg/L (1 ppm), with ease.
3 As we both do not know the amounts of sulphate present, you may have to first use a linear calibration curve with a large concentration range. When you have an approximate idea of sulphate concentration, you may then use a more finely tuned linear calibration curve, with a more narrow concentration range, which encompasses the approximate concentration of the sulphate found.
If your anion suppressor is not performing correctly, then you will have to repair it or not use it. As you are probably looking at high concentrations of anions, a suppressor may not be required. There are anion IC methods, where a mobile phase of 4 mM p-Hydroxybenzoic acid, 2.5%methanol, 0.1 mM sodium thiocyante pH 8.5, may be used, without a suppressor.
4 I cannot see an image, therefore cannot comment.