SrCO3 and Y-Oxalat precipitation measurement

[Andreas]

If we are using a proportional counter to determine Sr89/90 we have the problem that the SrCO3 precipitat and the Y-Oxalat curl up. Sometimes the precipitat contaminates the Window and we loose some of the probe and have now problems with the chemical recovery determination.
There are a lot of interesting tricks in the Labs. Could you describe your methode?

[Steffen]

Hi Andreas,

Well, actually this is more something I saw in a lab the other day, and basically it was more used for microprecipitated sources, I liked the idea and maybe it might work for your samples, too…
The lab’s been using 47mm cellulose nitrate filters for the µ-precipitation. After filtration they glued the filter (still wet) with some double-faced tape into 50mm steel planchets and fixed them with a stainless steel or aluminium ring (outer diameter 50 mm, corresponding to the inner diameter of the planchet, thickness of the ring about 2 – 3 mm). They then dried the filters fixed like that in an oven at approx. 40°C (I guess a couple of hours at RT will do to). The filter didn’t curl during the drying step, even after they removed the ring (anyway, maybe one could even measure when the ring is still in place to be sure?)
Only problem: I guess you’re determining the chemical yield by gravimetry? Might complicate that considerably… .
You could maybe try leaving the double-faced tape out and just dry the filter in this setup before removing, weighing and counting?

Might be worth a try, maybe somebody is already doing something similar?

Regards,
Steffen