Good result on rust with phosphoric acid 75%

[Sailingsaves]

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Following on from this thread, I have some results with regard to rust and small items.

http://www.ybw.com/forums/showthread.php?409086-Anti-Rust-Mixture-Bath

The phosphoric acid REMOVED all rust, left a grey surface that upon scratching revealed shiny metal.

The phosphoric acid left in shot glass has turned black and lost efficacy as I now have a spanner in there and the rust is not fizzing as much.

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Still have to wait to see how molasses works out.

https://www.youtube.com/watch?v=9ojyC6pRgMk&feature=youtu.be

The fizzing is great to watch.

 

[Champagne Murphy]

Always a good idea to remember that it's the same stuff they put in Cola! Fine if you already have dentures

 

[MM5AHO]

Hot dip Galvanizing requires the de-rusting of steel, and (in the UK) its normal to used HCl at about 5-10%.
It also leaves a grey surface that's clean of rust and millscale (another of iron's oxides, only forms at high temp).
But after so called "pickling", steel will soon start to rust again, so some prevention is then required.
This de-rusting technique is used on about 4000 tonnes of steel a week in the UK.

 

[VicS]

yes steel will rust again very quickly if de-rusted with hydrochloric acid but phosphoric acid leaves a phosphate coating

 

[kolster]

Always a good idea to remember that it's the same stuff they put in Cola! Fine if you already have dentures

Hopefully not 75%

 

[viva]

Where can you buy phosphoric acid?

 

[kolster]

Where can you buy phosphoric acid?

There seems to be quite a few choices on eBay, up to 81%

 

[TSB240]

Where can you buy phosphoric acid?

I think you will find that this contains a mild solution of phosphoric acid!

http://www.wickes.co.uk/Wickes-Grout-Film-Remover-1L/p/166088.

I have used it to polish up rusty stainless items, remove rust stains and stubborn waterline stains out of gf .

just clicked on safety data sheet link and it contains 15-30% phosphoric and 1-5% Oxalic!

 

[Sailingsaves]

Where can you buy phosphoric acid?

Yes, ebay.

 

[Sailingsaves]

great result.

View attachment 45987

Video at:

http://youtu.be/A1pDvt5CZqQ

The left over acid even worked really well on this spanner.

I have little use for this knowledge, but anyone with rusty stuff, phosphoric acid is great

 

[nigelmercier]

Where can you buy phosphoric acid?

I've used these sellers for various chemicals: http://amzn.to/1uMkkWI

 

[srp]

I bought an old pillar drill a few months ago, and derusted it with the electrolysis method (battery charger, washing soda solution, a plastic dustbin and a couple of bits of angle iron for electrodes). Did a superb job - some of the lightly rusted parts were in the bath for a few hours, and the heavy rust took about 24 hours. Used solution is not toxic so can just be tipped out in a far corner of the garden (I think the same applies to mollasses, but maybe not the case for phosphoric and hydrochloric acid).