Normal Phase Applications - Agilent Technologies 1260 Infinity II User Manual

Normal Phase Applications

Current passive inlet valves and outlet ball valves used with 1260 and 1290
Infinity pumps do not work well with applications using non-polar solvents as
for normal phase applications (e.g. hexane, heptane and CO
applications, pressure drops could be observed. They are a result of particles
electrostatically charging up in insulating solvents and sticking to the balls
inside the valves, such that the valves do not close properly any more after
some time of use (can be hours).
For normal phase applications, a second type of valves is available, which has
a design based on the existing one for 1260 and 1290 Infinity valves. These
valves use a new material for valve balls, which is a conductive ceramic and
replaces non-conductive ruby balls. The balls do not charge up
electrostatically and show good performance in normal phase.
The valves are marked with N for non-polar or normal phase.
Agilent recommends using these valves for (and only for) normal phase
applications.
No design change has been done for active inlet valves, which have already
been used successfully in the past for normal phase applications in 1200
Series and 1260 Infinity binary pumps.
Corrosion of valves
C AU T I O N
Normal phase balls/valves corrode quickly in aqueous solutions and acids (at or
below pH 7).
➔
The N-Valves have been tested successfully in using hexane at pressures below
100 bar; heptane can be used as a substitute for neurotoxic hexane.
InfinityLab LC Series 1260 Infinity II Binary Pump User Manual
Do not use normal phase valves in applications running with aqueous solutions.
Using the Pump

Normal Phase Applications

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