What material should be used for fluorination reactors?
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I’ve been carrying out a fluorination reaction using anhydrous hydrogen fluoride recently (hydrogen chloride is produced). The experiment was conducted in a stainless steel pressure vessel at a temperature of 90°C and a pressure of 1.5 MPa. After conducting the experiment several times, it was found that the rupture disc had been corroded through. Therefore, I would like to ask everyone: what material is used for reaction vessels in fluorination processes in industrial settings? How is corrosion prevention achieved? The reaction is endothermic; so how can the heating issue be addressed if PTFE is used as a lining?
The thermal conductivity of tetrafluorine is too low. I would be very grateful if experienced experts could give me some advice
Take a look at this post on the forum: http://bbs.hcbbs.com/viewthread.php?tid=339914
Reply to 3# yuchenchf: Thanks, buddy, but the problem still hasn’t been solved. Question 1: I’m not sure about the corrosive effect of a mixture of HF and HCl gases at 90°C on carbon steel I’ve heard before that some large companies use carbon steel to make fluorination reactors; using stainless steel would be a waste. Question 2: If the reactor is corroded by shrapnel, is it because it was exposed to air and came into contact with moisture in the air? Question 3: Hydrogen fluoride is highly toxic; how can the safety factor be increased? I earnestly ask all of you to share your insights
If carbon steel is used, how is the corrosion margin calculated? Seek experience
Reply to 5# zgvbb: We have not used hydrogen fluoride, but based on experience, it is advisable to use a larger safety factor in the design. For safety, a leak detection device is installed at the tank to provide timely alerts. It is best to empty it after it has been treated ； Or a safety rupture facility with higher safety levels.
This post was last edited by Litaotao1314 on 2012-2-29 at 12:30. Use a nickel-based alloy; don’t consider any other options
This post was last edited by yuchenchf on 2012-3-2 at 10:55. If PTFE is used, internal coil heating could be considered! Have time to chat!
I have seen graphite equipment used in the production of hydrofluoric acid.
Is it the fluorination of p-chlorotrichlorotoluene to produce a raw material for herbicides?
Previously, methane chloride reactors required a preheating temperature of 145°C, as this temperature prevents hydrogen chloride from corroding the metal. We are also conducting pilot tests on fluorination. The starting point is the chlorination of toluene to produce p-chloro and o-chloro toluene, followed by distillation for separation. P-chlorotoluene is first chlorinated using chlorine gas, and then fluorinated under high pressure using HF. We use stainless steel reactors; however, we did not install safety valves during the pilot tests, so there is no issue with rupture disks. If we produce the same product, we can engage in technical exchanges.