7N HCl 1

[joeswoes]

Could someone give me the equivalent (%) HCl. I am wondering if 316 stainless steel will have minimal corrosion rates at this concentration.

Thanks in advance.

 

[quark]

1N HCl = 1 gram equivalent weight/Liter of solution.

1 GEV of HCl = Molecular Weight of HCl/Valenc = 36.5/1

Therefore, 1N HCl = 36.5gms/liter and 7N HCl = 7*36.5 gms/liter = 255.5gms/liter which is 25% approximately (W/V)

 

[TD2K]

You'll need to supply the temperature of the HCl for someone to advise you of the corrosion rates.

 

[IRstuff]

Is this a tank or piping?

We always used Monel for HCl gas

TTFN

 

[moltenmetal]

Almost regardless of temperature, 316 SS is out. This is pretty concentrated HCl...Serious localized corrosion issues.

If it's cold (< 150 C), use plastics or plastic-lined equipment. Better to choose corrosion immunity rather than corrosion resistance...

 

[25362]

As a tutorial, have a look at Perry VI table 23-2. It gives a wide selection of materials and their resistance from 0 to 100% HCl, in the range of temperatures 0 to 300^oF.

 

[jahkid1]

I believe your post has pointed me in the right direction where my project is concerned although the acid is no HCl but nitric.
Thanks

 

[smckennz]

HCl will happily eat the 316 away. We use polypropylene at ambient temperature.
For nitric, 304 is better than 316 as nitric eats moly. At moderately elevated temperatures, 321 is said to be better.

The ASM book gives a more reliable reference.

Cheers

Steve

 

[unclesyd]

The cheapest way to go is 304L with a Carbon less that 0.020
321 SS will work but the fittings will get you. If you go this way make sure the welding rod is also has a restriced carbon.

Our Standard for all HNO3 was the above 304L though we further restricted the S and P for vessels and tanks.