multi-port valve for the chromatography

[gbern]

Hello all,
I am new here and already with the question.
We are trying to set-up a low-tech multi-user medium pressure chromatography station with the regular peristaltic pump and a column. Since the purification requires different buffers, we plan to connect all buffers to the main pump tube using multi-port valve manifold with 6-8 inlets and one outlet to the pump. We want users to change from one buffer to another by switching the valve manually. I found some round multi-port valves on Omnifit site, but it seems that since it's round it's easy to make a mistake and connect the wrong buffer.
I remember I saw somewhere the rectangular valve manifold with a slider switch. So it's one oulet on one side and six inlets on the other and the sliding switch can move from one inlet to another. The inlets can be clearly labelled so it's easier to use and lower chance of mistakes.
I was wondering if anybody here saw this kind of valve and can point us toward the manufacturer, or may be you know some other way to do the same.
Appreciate all your suggestions.
gbern

[Gerhard Kratz]

Please check on Buyers Guides from different magazines, or go on the Pittcon website www.pittcon.org and start a search for your switching valve. There are a few manufacturers producing such column, or solvent switching valves like Bischoff, Knauer, Rheodyne and some others. A switching valve must be round, but with a user friendly outfit. Good luck.

[tom jupille]

As far as I know, VICI (Valco, Cheminert) no longer make slider valves. The only one I know of from Rheodyne is a 3-way valve (A connected to either B or C).

As Gerhard wrote, a multiport valve pretty much has to be round. If it were my problem, I would mount the valve in a panel and clearly label the positions. There is no way to make it foolproof, because fools are extremely ingenious.

[Gilson_PLC2020]

It will cost a little more but have you considered an electronic switching valve with a digital display. That way there's no mistaking which position the valve is in, couple this to a laminated sheet detailing which buffer is which position and you can't go too far wrong. You can also use some colour coded nuts on the connections and similar coloured stickers on the tubing and bottles to minimise mistakes at the buffer end. Also have these colours referenced on the laminated sheet.

Some thing like this - http://www.gilson.com/en/AI/Products/17.12/Default.aspx