I am using ICP OES (610 and 460 WL) I want to make a Langmuir Adsorption isotherm. but getting very distorted results? I am using the (200-1000 PPM) LiCL range for exposure. the adsorbent is 3mg, volume 5 ml. I have already tried changing different variables like the range of lithium concentration and wavelength in ICP OES. please help..
Bharat Bhargawa
With your spectrometer, you can measure the concentration of lithium ions. Apparently, adsorption occurs from an aqueous solution. You need to determine the content of lithium ion in an aqueous solution, mix the adsorbent with a solution of lithium ion. The lithium ion is adsorbed on the adsorbent. Then it is necessary to filter the adsorbent with adsorbed lithium ion, and determine the content of lithium ion in the filtrate. By the difference between the first and second amount of lithium ion, you determine the amount of adsorbed lithium ion. With such a device, it is a sin to get bad results.
Professor Yuri,
Thank you so much for your kind response. could you please tell me the name of the spectrometer and wavelength?
I believe you are talking about AAS (atomic absorption spectrometer).
You are obviously confusing measuring and sampling. ICP will measure solutions, not dispersions and as Yuri Mirgorod explained, you'll need to filtrate after adsorbing Lithium onto your adsorbent. Or alternatively, you might centrifuge and collect the liquid fraction (potentially avoids adsorption on the filter), if and only if centrifugation agrees with your experiment (if Lithium is desorbed during centrifugation, forget about it). Then and only then will you be able to run the filtrate/liquid fraction through your ICP.
In any case, you should try both filtration and centrifugation to look for potential impact from one or the other.
Regarding ICP of Lithium, the main emission wavelenghts are 670.784 nm (most sensitive) and 460.286 nm (interfered by Zr and Th). My advice would be to acquire absorption at both wavelengths if you don't know what to expect : results are quite the same, everything is OK ; results differ, you have interference issues.
Lithium should be easy on an ICP-OES, even at trace levels (LODs of a few ppb at 670.784 nm).
Bharat Bhargawa
Instead of me, Pierre Caulet explained everything to you once more in detail.