Reason for the yellow-brown color of the saltwater inlet and outlet hoses in ion membrane electrolyzers
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This post was last edited by sunjl1981 on 2013-1-6 at 21:33. In our plant’s Asahi Kasei ion-exchange membrane electrolyzers, the inner surfaces of the hoses for saltwater inlet and outlet develop a yellow-brown color over time as a result of prolonged operation. However, all parameters related to pure water and secondary saltwater are within acceptable limits. What could be the cause of this phenomenon? # hcbbs
Import and export?? Or just export?`
When the iron ion level is too high, over time both the inlet hose and the outlet hose turn yellow-brown in color.
Do you use refined salt? If so, it is likely due to potassium ferrocyanide – refined salt contains this substance as an anti-caking agent, and iron is present in the form of ferrocyanide complexes. ICP analysis cannot detect iron in this form, which is why the outlet hose changes color. It is recommended to use unrefined salt whenever possible
The ion exchange membrane has been in operation for over 3 years now. Initially, only the soft hoses carrying fresh brine leaving the tank turned yellow-brown, but by June of this year, the soft hoses carrying brine entering the tank also became yellow-brown, with the color deepening gradually from the entrance to the exit of the tank.
I usually use industrial salt, with 80% being brine. What is wet salt?
1. Was too much FeCl3 added? 2. Is there any peeling of the rubber lining on the equipment, resulting in an excessive level of iron ions?
1. It involves checking the content of potassium ferrocyanide in the raw salt. 2. It checks whether the amount of iron ions in the brine increases during the process from primary brine to secondary brine.
1. Check whether the content of potassium ferrocyanide in the raw salt exceeds the specified limit. 2. Check whether the level of iron ions increases as the brine moves from the primary brine stage to the secondary brine stage. 3. Check the acidity at the anode outlet of the electrolyzer. 4. Determine whether all the outlet hoses have turned yellow or only some of them; also check for any pinholes in the ions. :handshake
Our factory uses chlorine-based processes, and this situation also occurs there
Regarding this situation, there have already been discussions on the forum; the main reasons are refined salt, as well as the silicoaluminates brought in with the saltwater.