Kitchen chemistry

[urbantangleweed]

A rusty water pump cover presently marinading in lovely hot citric acid solution 😊

[dc]

Works out cheaper than Deox-C.👍

[urbantangleweed]

Apr 21, 2024 19:27:11 GMT 1 dc said:

Works out cheaper than Deox-C.👍

Yep, and it's doing a lovely job too.

[dc]

Be sure to post the finished item.

What dilution did you use ?

[urbantangleweed]

Apr 21, 2024 20:42:01 GMT 1 dc said:

Be sure to post the finished item.

What dilution did you use ?

Always 40 grams per litre of water.

[reedpete]

For those new to citric ( I’m a long time fan , particularly on chrome parts) … the mix ratio ‘doesn’t matter’… means , there no right or wrong , just consequences…
Citric is an organic acid so it’s disassociation is quite week which means you need a reasonable mol mix to get the required ion concentration… but that’s only one variable in the reaction time. Surface area , time and temp are the others.
Plus remember that the citric acid is ‘used up’ as the rust is converted so whatever you start with will dilute down ..

Too strong is not a problem but wasteful as a 1kg bag will last a long time if used wisely..

Time is your friend… think of this as best being an overnight process.. sit the part in a solution and walk away, a good scrub half way through in plain water is a good idea to loosen off flaky rust that then doesn’t need be reacted… also allows you to monitor progress.

Also remember that after de rusting you do need to do something else otherwise it will flash back over, paint strip and prime or ACF50 if you want it to be left as is.

[urbantangleweed]

Photos 1 and 2 are straight out of the solution, 3 and 4 are after a scrubbing brush session, 5 and 6 are after gasket remnant removal and a bit of P1500 wet and dry action:

    

  

[dc]

Good result. 👍