Sciencemadness Discussion Board

hot acid resistant coating for steel

roy30103 - 16-9-2011 at 00:22

I would like to coat a steel reaction vessel so it can withstand hot HCl. I am considering enamel but I need a recipe that is used in the industry.

dann2 - 17-9-2011 at 03:26

You could coat with Ta, not too simple though.

Can Teflon bags be purchased. You could perhaps place one inside the vessell.

I cannot get a paper on Ta coating to attach, will try later.
It involves a molten Ta salt.

[Edited on 17-9-2011 by dann2]

Chordate - 17-9-2011 at 04:09

Used in industry? usually thats done by either teflon, ceramic, or glass coating.

Theres a couple of ways to go about glass coating steel. Industrially, this is done by thermal decomposition of silane. This... is troublesome, Silane is a pyrophoric gas and decomposes at 400-500 degrees. Lower temps can be achieved by using hydrogen fluoride gas . Industrially: this is doable. To you or I, this seems like a real good way to die.

Now, a little while ago some chaps figured out how to make really fine particles of sillicon dioxide, which can be turned into a suspension which just sprays right onto materials and renders them pretty chemically inert. Awesome! They are holding on to their method and their supplies very tight-fistedly. This is unsurprising, because microstructured sillicon dioxide is probably not the healthiest thing to be handling either.

That said there are a few people out there who will apply such a coating for you professionally. I just have no idea how much it costs. Glass coating is nice for its thermal properties

Alternatively, there are some people who make chemically resistant thermal-set epoxies which are designed to be applied to steel. These guys came up on a quick google search. Googling for chemical resistant epoxy though will give you an idea of whats out there.

Endimion17 - 17-9-2011 at 04:36

Steel reaction vessel? Is it steel because the vessel is to be pressurized? If it is, you need to mention that. If there's no extra pressure, why not simple borosilicate glass?
How hot acid are we talking about, and what's the pressure?

roy30103 - 17-9-2011 at 22:52

OK, more info
I want steel because of about 100KPa gauge pressure. Bake-ware enamel would probably work fine. I have some frit made from borosilicate glass. I was wondering what additives to put with the frit.

dann2 - 18-9-2011 at 05:39


Paper here on Ta coating.


[Edited on 18-9-2011 by dann2]

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