Magnesium perchlorate (Mg(ClO4)2) is used in Isotopic Ratio Mass Spectrometer (IRMS) to trap moisture from the gas. Is there any other alternative for this or this one is best?
Dear Mohammad Tauseef!
I have listed mostly used Drying agents (desiccants)
1. Absorption tube for H2O
H2O absorption tubes are used to keep reagents or solvents dry
2. Calcium chloride (anhydrous powder)
It is used for drying Acetone; ethers; numerous esters; aliphatic, olefinic, aromatic and halogenated hydrocarbons; neutral gases
3. Calcium oxide
It is used for drying Neutral and basic gases; amines; alcohols; ethers
4. Desiccant sachets [SiO2]
It is used for drying Humidity
5. Magnesium perchlorate
It is used for drying Inert gases; air; adsorbs ammonia as strongly as water
6. Molecular sieves
It is used for drying nearly all gases and liquids
7. Phosphorus pentoxide
It is used for drying Neutral or acid gases; saturated aliphatic and aromatic hydrocarbons; nitriles; alkyl and aryl halogenides; carbon disulfide
8. Silica gel [SiO2]
It is used for drying practically all gases and liquids
You may add "drierite" (calcium sulfate) to the list, sometimes with an activity indicator. Some cited desiccants can be regenerated by heating, some are strong but not chemically inert as indicated (P2O5, is acidic, CaO is basic, etc.). Anhydrous sodium sulfate (very mild) and magnesium sulfate (mild) are somewhat neutral.
I forgot to tell that your application is very specific. If you look at carbon isotopes by combustion/oxydation, CaO (basic) will trap CO2 (weak acid). If you change the drying mode you may have to recalibrate or validate the method.
Dear Mohammad Tauseef this is a very interesting technical question. In general, I would be very careful when handling perchlorate salts due to their potentially explosive nature. Thus I would generally reduce the amount to a minimum and avoid any heating of the salt.
Beaides this safety advice, magnesium perchlorate (Mg(ClO4)2) has been reported to be a convenient and reliable drying agent for this particular purpose. For more information please have a look at the following freely available RG link:
Magnesium perchlorate as an alternative water trap in AMS graphite sample preparation: A report on sample preparation at KCCAMS at the University of California, Irvine
Article Magnesium perchlorate as an alternative water trap in AMS gr...
Thus there is apparently no need to look for any alternatives.
- Badges
- Science topic