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Coating to resist aqua regis

Is there any coating on metal surface that resists corrosion of aqua regis? I have a project to process sludge contaminated with heavy metal and aqua regia. The plate and frame dewatering equipment needs the coating to protect metal surface of the equipment from aqua regia corrosion.

Tony Lee
corrosion prevention - Grand Prairie, Texas
2004

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The metal finishing industry uses filter presses with polypropylene plates almost exclusively, and you might want to consider whether that is a better answer than a coating. Plastisol coating or teflon coating should do the job on the frame, but these coatings are of obvious thickness (something like 30 mils), they're not just paint.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2004

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Tony,

Ted is right again (then I haven't noticed him being wrong about most things, either!)

Firstly, to transport your sludge, go to Pe pipe (pressure pipe is now available up to 5 feet dia.) and then, as Ted said, go to Plastisol.

I wouldn't even consider teflon. Too expensive to buy and to apply. A TFE coating would not be nearly thick enough to withstand abrasion.... just use a PVC plastisol.

Freeman Newton [deceased]
(It is our sad duty to advise that Freeman passed away
April 21, 2012. R.I.P. old friend).
2004