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- Posts: 405
- Joined: Wed Jul 18, 2012 6:45 am
- Location: Germany
This is not chromatography related, but I know there is other lab hand-work experience around here
Here is the challenge: We have pressure sensors for bottles we use in CO2 evolution tests used for biodegradability studies. The volume of every bottle is determined individually and a known amount of water is added so that the pressure is proportional to the amount of gas evolved. These sensors are calibrated using VERY expensive tablets that look a bit similar to effervescent tablets, only smaller. We have tried to use Magnesium tablets from the drugstore (larger, but work), but these show relatively high variation in the final pressure, so they cannot be used for calibration.
I thought about adding a known amount of analytical grade hydrogen carbonate and excess acid to allow quantitative formation of CO2. Problem: The gas evolution starts before I can close the bottle tightly. I need something which delays the gas formation. Any ideas are greatly appreciated.
Thanks
Jörg