Benzene Material Selection/Corrosion Rates 1

[UKCats]

Looking at using benzene as a solvent up to 300F. It appears carbon steel has less than 2 mpy under 100F (storage) and 316SS up to 150F at higher concentrations. However, benzene will vary in our seperation column (0-100%) and I have found Alloy 20 to be acceptable to 212F in several literature databases.

Have no ideas above 212F at various concentrations? Any ideas where I can go for help?

 

[cap1aa]

First of all, the corrosion rate based on literature is laboratory data. It doesn't consider the effect of protective film(like FeS as a corrosion product) and chemical injection and so on. Some data book from NACE, they recommend up to 50 mpy as a limitation. So, sometimes corrosion rate doesn't have any meanings practically.
In general, whether stainless steel must be used or not is from several purposes. Those things are
1. High temperautre (<about 580C)
2. Corrosive Condition (protecting by chromium oxide)
3. Low temperature (below -70C)

Practically, most of material used in Bezene plant is carbon steel. The reason why is that there is no conditions to use Stainless steel cosidering above 3 conditions.
I strongly recommend carbon steel as a proper and suitable material instead of SS or high alloy.

 

[UKCats]

Carbon steel all the way up to 300F???

 

[cap1aa]

If there is nothing connected with the above No. 1,2,3, Carbon steel is perfectly okay at that temperature.

 

[StoneCold]

I am going to throw this out there, I am sure that you know already but I am going to say it. Benzene is pretty hard to get a hold of in the US. Carcinogenic, water contamination issues have given it a bad name and normally never used anymore as a process solvent. You may want to re-think the use of benzene as your solvent. Toluene still considered ok. Tetrahydrofuran or better methyltetrahydrofuran can disolve just about anything and they are still considered better than benzene, health wise.

Just a thought.

Regards
StoneCold

 

[strider6]

you can search in Corsur of NACE, you find it at:

http://www.knovel.com/web/portal/browse/display?_EXT_KNOVEL_DISPLAY_bookid=532

S

Corrosion & Rust Prevention Control