NOTICE

Forums are temporarily disabled while we are working on a new login procedure.

When migrating the old forums over to our new forums we were unable to retain the identity of the authors, so the old posts will show up as "anonymous". All NEW posts will show up credited to their authors. So please participate and share knowledge just as you have in the past.

You must log in if you are an existing user or register if you are a new user in order to contribute to the discussions.

Discussion Forums - The Hendrix Group
HomeHomeDiscussionsDiscussionsMaterial Select...Material Select...Best material for Boiling Sulphuric acidBest material for Boiling Sulphuric acid
Previous
 
Next
New Post
2/14/2008 9:00 AM
 
Please advise of the four options given by my supplier to minimize corrosion, storing boiling sulphuric acid - Graphite impregnated with PTFE resin, 20 Cb-3 stainless steel, Titanium and Hastelloy C.
 
New Post
2/15/2008 9:00 AM
 
If you consider cost factor then PTFE coated bolts will do the intended service provided without any acid spillage over the bolts otherwise Hast-C is a better option. regards,
 
New Post
9/20/2008 9:00 AM
 
Dear Gurdeep, It may be a bit late reply to your querry, but I thought the following input may of assistance to you. Out of the materials that you have mentioned, only Hastlloy C and 20 Cb-3 are the most appropriate material to be considered for storing boiling sulphuric acid. One thing that may be added that sullphuric acid occupies two positions regarding oxidizing or reducing acid. At below 85% by weight at room temperature, sulphuric acid is a reducing acid while at higher concentrations, it becomes oxidising acid. Hence, material selection should also take this switching nature of the acid in account. Alloy 20 and Hastelloy C shows similar corrosion resistant in sulphuric acid. However, there are certain advantages in using Alloy 20 over Hastelloy C for storing boiling sulphuric acid. Alloy 20 was originally made for handling sulphuric acid and in my experience, it is quite resistance in boiling 20% to 40% concentrations. If you can provide at what concentration you intend to store the acid, we can provide you a better suggestion. Alloy 20, at higher concentrations at boiling point will have a maximum of 50 mils as corrosion rate while Hastelloy C can have over 200 mils at similar concentrations. Also, Hastelloy C can be pretty vurnerable to stress corrosion cracking if chloride concentration is more that 40 ppm in the acid. Based on the above and within the choice of materials that you have provided, I would recommend Alloy 20 for the intended application. By the way, you may also like to consider Durion which is high silicon cast iron which can be used at temperature as high as 500C. However, there are some limitations in using Durion. One of them is not to use above 100% concentrations in fuming acid. Hope the above is helpful. Please do let me know should you have any further querry. Regards, MetcorrH
 
New Post
9/24/2008 9:00 AM
 
hello just to add some info that may be useful: http://www.norfalco.com/documents/NorFalco_H2SO4TechBrochure.pdf http://www2.dupont.com/Clean_Technologies/en_US/assets/downloads/Equipment_FAQs.pdf SELECTION AND PERFORMANCE OF STAINLESS STEELS AND OTHER NICKEL-BEARING ALLOYS IN SULPHURIC ACID http://www.corrosionsource.com/technicallibrary/nidi/literature/pdf/10057.pdf?bcsi_scan_34B9664DEF68CC68=1 hope this may help u S.
 
Previous
 
Next
HomeHomeDiscussionsDiscussionsMaterial Select...Material Select...Best material for Boiling Sulphuric acidBest material for Boiling Sulphuric acid


  

News

With a little delay, our Calculation of Ammonium Salt Deposition Temperatures...read more
Our sulfidic corrosion calculators are now available at hghouston.com/calcula...read more

Stay Current

Sign up for our quarterly newsletter

covering updates on corrosion

Sign Up