Re: ORGLIST:Details of Kipps-like generation of CO2?

Date view Thread view Subject view Author view Attachment view

From: Jacob Zabicky (zabicky$##$bgumail.bgu.ac.il)
Date: Mon Aug 26 2002 - 03:55:17 EDT


Hello Fergus,

Two alternatives for which you have to decide the actual size of parts you need.

1. IMHO the simplest. You need a glass stopcock or a needle valve or any
flow regulating device, with one outlet long enough to dip into the
solution, the other one wide enough to stick into the opening of a rubber
baloon (you may need to reinforce that with a rubber band or a bracket so
the baloon doesn't fly away) . Open the valve, inflate the baloon with CO2
from a cylinder to a reasonable size, close the valve and stick the long
end in your reactor. Voila! Keep a few baloons handy for replacement.

2. I'm looking into a "Fisher" catalog, any other catalog may be fine. The
only thing that is important is the shape of the parts. You decide on the
size. In the Distillation section youl find "Pyrex brand vacuum type
distillation traps," you'll need two of these, not necessarily of the same
size (they will be parts A and B). In the Funnels section you'll find
"Cylindrical separatory funnels," you'll need one of these (part C).
Connect the side tube of part A (the bigger one) to the vertical tube of
part B. Put some glass wool (rather loosely) in the side tube of part B and
connect that to a tube dipping into the solution. stick the stem of part C
into the vertical tube of part A and seal the space between the tubes.
Place some dilute H2SO4 in the vessel of part A and some concentrated H2SO4
in the vessel of part B (the vertical tube of part B should dip into the
acid). Close the stopcock of part C and place some Na2CO2 solution in the
cylinder. Carefully open the stopcock of part C and start generating moist
CO2. The moisture will be absorbed in part B. The glass wool serves to
knock out any droplets of acid that will interfere with the Grignard
synthesis. You may sort out the details of concentrations a dripping rate
of carbonate solution.

Have fun,

Jacob

At 18:35 21/8/2, F.J. Lalor wrote:
>Ok - I am fully aware that this is a shamefully elementary question
>so no finger-wagging from the intellectual elite please 8-)
>For the purposes of a u/g lab experiment I need to generate small
>quantities of CO2 - preferably from a Kipps apparatus or something
>similar - to do a small-scale carbonation of PhMgBr. (Of course a
>cylinder would be easier but .... well, there are reasons). Now of
>course I know that all I need to do is drop sulphuric acid on calcium
>carbonate. Problem is I cannot find specific details anywhere. All
>the older practical textbooks in our library that might have
>described the experiment have long ago been dumped. So do I need
>conc. or dilute sulphuric acid? How do I dry the CO2 and avoid
>entrainment of acidic vapours? Any and all advice will be most
>gratefully appreciated.
>Regards -
>Fergus Lalor
>--
>
>--------------------------------------------------
>Dr. Fergus Lalor, Senior Lecturer, Chemistry Dept., University
>College, Cork, IRELAND.
>Telephone: 353-(0)21-4902317. Fax: 353-(0)21-4274097
>
>
>
>_______________________________________________
>ORGLIST - Organic Chemistry Mailing List
>Website / Archive / FAQ: http://www.orglist.net
>To post a message (TO EVERYBODY) send to everybody$##$orglist.net
>To unsubscribe, send to everybody-request$##$orglist.net the message:
>unsubscribe your_orglist_password your_address
>List coordinator: Joao Aires de Sousa (coordinator$##$orglist.net)

x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x
Prof. Jacob Zabicky
Institutes for Applied Research
Ben-Gurion University of the Negev Private: POB 12366, Beer-Sheva 84863
POB 653, Beer-Sheva 84105, ISRAEL Tel. +972-8-6496792
http://profiler.bgu.ac.il/site/main.cfm
Tel. +972-8-6461271/6461062/6472754
Fax. +972-8-6472969
x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x-x

_______________________________________________
ORGLIST - Organic Chemistry Mailing List
Website / Archive / FAQ: http://www.orglist.net
To post a message (TO EVERYBODY) send to everybody$##$orglist.net
To unsubscribe, send to everybody-request$##$orglist.net the message: unsubscribe your_orglist_password your_address
List coordinator: Joao Aires de Sousa (coordinator$##$orglist.net)


Date view Thread view Subject view Author view Attachment view

This archive was generated by hypermail 2.1.4 : Fri Sep 19 2003 - 12:16:54 EDT