Ni alloys aquous corrosion

Hi everybody,

This article is very good where they talk about how various Ni alloy’s corrosion rate is sensitive with the various corrosive species like Oxygen,Organic acid,HCl etc.where I noticed that there is stip rise in corrosion rate of Monel when oxygen / air presence.

Thanks & Regards

http://files.engineering.com/getfil...cee6ece5&file=Aqueous_Corrosion_Ni_Alloys.pdf

 

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In HF alkilation units service oxygen is prone Monel.

Oxygen dissolves in, and tends to stay with, the HF acid and accelerates corrosion of, Alloy 400 and copper alloys. It can enter the unit through a number of sources including imported feedstock, FCC wet gas compressors, improper operation of a caustic treating unit, or improperly charging fresh acid into the unit, particularly if oxygen contaminated nitrogen is used. Oxygen is extremely difficult to monitor once it gets into the unit, and can only be removed through the venting of non-condensables into the flare header.

Luis Marques