Calcium bicarbonate

Tara Kennedy <tkennedy [at] mail__state__ne__us> writes

>I need to do one paper treatment using calcium bicarbonate as an
>alkalizing agent. Does anyone have any tips as to how I could make
>up calcium bicarbonate without having to rent a CO2 tank? I thought
>about the soda siphon trick from Anne Clapp, but calcium carbonate
>is not as soluble in water as magnesium carbonate. I cannot/do not
>want to use magnesium bicarbonate. Does anyone have any suggestions?

There is one way I know you can make calcium carbonate without CO2
which needs to bubble through  water in order to dissolve the
carbonate. You should look for a building construction site and
kindly ask if they have by any chance quick lime in a tank or barrel
in a water suspension. You carefully collect the clear water above
the quick lime. You must be very careful not to shake the quick lime
below or you`ll get an unwanted milky and not clear solution. Be
aware also that quick lime is very reactive and I recommend you use
protective gloves and eyes protectors as well. Back at your
Laboratory/studio you should dilute the solution with fresh water to
reduce the alkalinity to pH 8 for deacidification treatment. Good
luck, and keep in mind that quick lime is a dangerous material!

Michael Maggen
Head of Paper Conservation
The Israel Museum Jerusalem
PO Box 71117
91710 Jerusalem Israel
+972 2 67 08808
Fax: +972 2 6771332


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                  Conservation DistList Instance 18:4
                  Distributed: Thursday, July 1, 2004
                        Message Id: cdl-18-4-008
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