[archmagi101]

Hello all!  I am currently in the process of setting up a water cooling system for a PC, and have a question in regards to the effects a higher pH alkaline solution would have on the copper radiator blocks, and if the alkaloid in question could have any additional issues it could cause.  I will explain.

I am attempting to visually recreate the Cherenkov Effect within the confines of my computer rig, and after several hours delving through various internet forums and posts, I came across an interesting solution; Quinine.  Quinine, when exposed to UV light, glows an ghostly bluish tinge very similar to the desired color scheme, so it seemed like it had great potential.  Unfortunately, I discovered that just 1 gram added to 1.9L of distilled water created an alkaline solution with a pH of >9.5. 

I am curious as to what sort of issues might arise from using such a solution within a cooling system.  The majority of components are either brass, copper, or nickel, as well as plastic tubing (probably some version of Tygon).  How much corrosion would stem from having such a high pH solution in a cooling system like this?  Temperatures will probably range from room ambient to 5-10 degrees higher; will this cause any adverse reactions?

I do apologize for the length of my question, but beyond a couple posts discussing the benefits of corrosion inhibitors and their inherent high pHs, I have found nothing relevant to using Quinine as a basic in this sort of system.  Certainly seems like a lot of effort for something visually appealing, but it also has the potential for causing less damage than various color-added coolants.

Thank you for any replies.

[Honclbrif]

http://www.sandvik.com/sandvik/0140/internet/se01659.nsf/HandbookWeb/E17B1ADC80978BB64125662D003B2A41

http://www.deepdyve.com/lp/springer-journals/eco-friendly-corrosion-inhibitors-inhibitive-action-of-quinine-for-4u0m9t0umX

One source claims it will corrode steel, another claims it will inhibit the corrosion of steel. Seems kind of dicey.

You could try putting a piece of copper tubing in your solution and see what the effect is, but if you're running this through valuble equipment I would err on the side of caution.

There are other fluorescent blue dyes out there besides quinine. Shop around the interwebs and see what they turn up.

[archmagi101]

Thank you for the quick reply, Honclbrif.  The bottom link got me browsing through various eco-friendly corrosive inhibitor journal entries, so I have far more material to read up on this topic, now, which is awesome.  I agree that a personal experiment might be needed, possibly with a tonic water substitute for the time being ( sugarless and sans carbonation, of course  ) just to see if it has any obvious, short-term degradation with various copper and brass components.  I will try to follow up in the future with what I discover, and thanks again.

[nox]

I wonder if Methylene Blue would work for your purpose.