Hi,

We are recently using HP-5 & HP-1701 capillary column for pesticide residue analysis. I wanna know the precutions we have to follow to increase the column life time. what type of solvents or chemical compounds that we mustn't inject into this columns or those which may decrease the columns life time.

Thanx and best regards

Hello,

To increase the lifetime or your columns take care to stay behind the temperature limits of your columns.
Staying at the maximum temperature of the column will seriously decrease their lifetime.
From head with the 1701 don't go over 280°C and the HP-5 about 325°C.
You could also filtrate your samples especially when you could have some salts in the sample you'll inject.
Then always dilute carefully your sample (acidic compouds with the combination of high temperature are always source of trouble).

Laurent

Respect the maximum allowable temp from manufacturer,this depends also in the film tickness of your column,not only on the phase type.
This temp are written on the column badge,the first is the max isothermal temp where you could stay as long as you want,without damage the phase,the second is the max temp where after 10-15 min the phase begin to degrade....and the lifetime decrease.

See You

Thank you all for your precious information. I would like to know the type of solvents or chemical compounds that we mustn't inject into those columns

Thanx and best regards
Emad

For my part I mainly use the dichloromethan or methanol.

Laurent