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mobile phase pressure in binary pump
Posted: Fri Jan 07, 2011 4:38 pm
by che313
our agilent 1200 is conssited of binary pump concetd with 50x2.1 PFP propyl 5um coulmn.
mobile phase A is water with 0.2% formic acid & ammonium formate, mobile phase b is acetonitrile with 0.2% formic acid & ammonium formate. when A is 100% the pressure is more than 200 bar and when b is 100% pressure is 100 bar!!
Is this situation regular?
flow rate is 1 mL/min
Re: mobile phase pressure in binary pump
Posted: Fri Jan 07, 2011 5:24 pm
by tom jupille
The viscosity of water is higher than that of acetonitrile, so yes, the difference makes sense.
Re: mobile phase pressure in binary pump
Posted: Fri Jan 07, 2011 8:37 pm
by bisnettrj2
http://www.separatedbyexperience.com/ar ... C012_1.jpg
http://www.separatedbyexperience.com/ar ... C016_1.jpg
Tom's correct. For more information, see the links for charts with the properties of different solvents, including viscosity.
Re: mobile phase pressure in binary pump
Posted: Sun Jan 09, 2011 7:40 am
by che313
thnx tom & bisnettrj2
but coulm output n this situation are differs, i.e. in water case it is droping and in acetonitrile it is jetting!!
Re: mobile phase pressure in binary pump
Posted: Sun Jan 09, 2011 8:39 pm
by tom jupille
water has a higher surface tension than does acetonitrile so the drops tend to "hang together" better.
Re: mobile phase pressure in binary pump
Posted: Mon Jan 10, 2011 12:16 am
by carls
Sounds like your solvent lines have been crossed somewhere. Follow each line from the reservior all the way to the pump to ensure the system is plumbed correctly. Perhaps someone mistakenly plumbed A to B at either the degasser or the solvent selection valve
