Pipe material for H2SO4 (93-98%)

this is belong to dense sulfuric acid. I remember the stainless steel can do the trick.

(include steel material)

Provided no water gets into the stream then mild steel will do satisfactorily. If water cannot be excluded, try rubber-lined mild steel or PVDF, perhaps.

93% - 98% Sulfuric Acid at 65 degrees C is most corrosive to metals at the lower 93% concentration. I do not recommend using mild steel or rubber lined mild steel pipe with 93% - 98% Sulfuric Acid at 65 degrees C. I wouldn't use 304 SS or 316 SS pipe with 93% Sulfuric at 65 degrees C without doing a corrosion tests. PVDF is probably the best material to use under these conditions. I suggest you ask your PVDF pipe supplier about its pressure rating at 65 degrees C and 75 psig.

I once helped design an electroforming line for copper foil. We used sulfuric acid based plating bath to plate the copper onto a stainless steel drum then striped it off and post-processed it before winding onto a coil.

We used 316L and specified material be selected for "extra-low carbon" for the drum and the piping between the copper digester and the plating tank. Unfortunately, I cannot recall the concentration of sulfuric acid.

Hello, we just finished doing some repair to our sulfuric acid tanks and piping at th e mill I work in. All of our pipe is carbon steel for the 98% acid. I do not recommend stainless such as 316 or 304, we have had allot of problems with it especially on the lower concentration sulfuric lines. Many times I have installed cast iron with a Kynar liner for sulfuric or just Kynar tubing where there is not a Chance for physical damage to the pipe.You can also run the Kynar tubing inside another less expensive pipe if you need protection from something damaging the tubing from outside. I ran a 1", 5% waste sulfuric pipeline from Sch. 80 CPVC with a 2" galvanized outside pipe protection sleeve several years back and it is still doing well. I have had very good luck with vinyl ester liners and HDPE pipe on large effluent lines where low concentrations of acid are present as well. if you want to go all out and install something that will pretty much be maintenance free I would suggest Carpenter 20 (Hastelloy, alloy 20) although it is very expensive. We have a few places that this is the only thing that will work such as a steam sparger in tall oil reaction tanks, and/or brine tanks where the heat and the reaction of the acid/brine is really strong.

Dear every body

I noted with many thank to your opinion/advice. After consideration technical and investment cost. We decided to used CS for sulfuric acid transfered pipe.

Due to the reasons as below:

1) CS can be used for this case (NACE RP0294)

2) Investment Cost is acceptable (The line sizing is large (16inchs), the pipe length is far (appx.2.5km))

But, I just had the very old NACE RP0294 version. can every body advise me that where i can find out the new version for this standard?

Dear doctor dissolvo

Thank you for your advise.

316 SS will corrode at greater than .020" per year,as will carbon steel. Carpenter 20,Hastelloy B and Hastelloy C will each corrode less than .005" per year. Also Tantalum is less than .005" per year. This is at 25C,so expect more at elevated temperature. Teflon is generally suitable, as well as Kynar, natural rubber, and epoxy fiberglass.--------------------------------------------------------------------------------------GUEST

A good source of information is the supplier of the <...sulfuric acid (93~98%)...Temp. Nor. 40Deg.C, design. 65Deg.C...Press. approx. 5barg...> as it will not want any civil liability arising from the downstream user getting it wrong. Telephone?