What does Star San turn into when it ceases to be active?

[raven19]

Let's say you drop your cleaned and sanitized racking cane onto the ground. On one side of the room you have an open bucket of VERY, VERY old Star San. On the other side, you have a bucket of tap water. Into which do you swish your racking cane before you siphon your precious beer? For this question, assume that there are no other options.

I would be ensuring a good batch of sanitiser was available and ready for use.

Last thing you want to risk is infecting that precious beer.

[Cliff]

One of the by products of mineral acid decomposition are salts. Another will be hydrogen ions. Depends on the acid what else will result.

Dodecylbenzene Sulfonic acid is organic so it'll give off hydrocarbons and I'd guess sulfur ions galore. But it is not a simple subject,
Here is a whole huge paper on decomposition of that one acid
http://www.enveng.tuc.gr/Downloads/Mant ... aper38.pdf
There are industrial processes that break it down to capture and use the by products.

Phosphoric Acid is a mineral (inorganic) acid

[Charlie]

We use octane sulfonic acid and dodecyl sulfonic acid as ion pair agents to separate neurotransmitters by HPLC.

H3PO4 + 3(OH-) ---> H2PO4- + H2O + 2(OH-) ---> HPO4-- + 2H2O + OH- ---> PO4--- + 3H2O

I think we were in the same analytical chemistry class.

Charlie

[ajdelange]

I guess I did take qual which I had completely forgotten about until I saw this post. Thinking back on that course I am sorry to say that the only thing I remember about it was that one of the three girls (in the whole engine school) approched me in the lab and asked if she could use my cathode. I chuckled then and I chuckle now.

[spiderwrangler]

Thinking back on that course I am sorry to say that the only thing I remember about it was that one of the three girls (in the whole engine school) approched me in the lab and asked if she could use my cathode. I chuckled then and I chuckle now.

HAHA... so, did you give it to her?

[Buttwidget]

I guess I did take qual which I had completely forgotten about until I saw this post. Thinking back on that course I am sorry to say that the only thing I remember about it was that one of the three girls (in the whole engine school) approched me in the lab and asked if she could use my cathode. I chuckled then and I chuckle now.

Not as much as she did when you showed it to her...

Couldn't resist, sorry

~widget

[ajdelange]

Well I wouldn't say that. I had it out on the bench in plain view and I think she was rather impressed with it.

[scotchpine]

Ok AJ, since the topic has turned to those being impressed with your equipment, curiosity just led me to the photo archive of your home brewery build from 2001-2007. It left me shaking my head in amazement. Great photo documentary. I guess I shouldn't be that surprised that you built a 1.5 barrel nano brewery in your garage, but the level and extent of that equipment is ridiculous for a home brewery. I'm not aware that you brew for commercial purposes so I suppose it's for your combined brew sessions with your club cause there is no way, if you drank that much beer, your brain would still function at the extremely high level it does. Thanks again for all the helpful info you have extended to myself and others on this forum. U da man.