R-23 Recovery From H2 and Contaminated With H2O

Dear colleague,

The appropriate molecular sieve packed in a column will do the job.

Sincerely,

Jacob Scheinert

Thank you. Will molecular sieve separate all three impurities? (H2, water, CO2?). I didn't think it would do anything for the H2 and believe the CO2 capacity is limited.

Is there a better way to get rid of relatively large amounts of CO2 (I had a typo in the original posting, it is closer to 1000-2000 ppm Vs 100 ppm stated)

A dessicant dryer will do wonders for the water, so we can effectively deal with the water fairly easily.

R-23 is much denser than air whereas hydrogen isn't. You could probably use some kind of hydrocyclone to separate the two but it won't do much for the CO2. But an easier way to deal with that (and it would work for the CO2 as well) is a molecular seive as was stated previously. R-23 molecules are pretty big. CO2, not so much. H2 is even smaller and to be honest with hydrogen, the trick is usually to keep it IN, not out. It is so small it will seep through steel itself (slowly granted). so you could use a series of molecular sieves to sort the dry mixed stream into H2, CO2, and R-23.

Another way to skin the cat would be to refrigerate and liquefy them. H2 won't liquefy until you get it pretty dang cold. the boiling point at 1 bar is something like -82C for R23, CO2's boiling point is -78.5C, H2's is something like -259C, so that is another way you could separate the streams.

BTW, this is a nice little site by Air Liquide for various industrial gases.

http://encyclopedia.airliquide.com/Encyclopedia.asp?LanguageID=11&CountryID=19&Formula=&GasID=36&UNNumber=&EquivGasID=26&PressionBox=&VolLiquideBox=&MasseLiquideBox=&VolGasBox=&MasseGasBox=&btnMSDS=0&MSDSLanguageBox=11&RD20=29&RD9=8&RD6=64&RD4=2&RD3=22&RD8=27&RD2=20&RD18=41&RD7=18&RD13=71&RD16=35&RD12=31&RD19=34&RD24=62&RD25=77&RD26=78&RD28=81&RD29=82