Aluminium corrosion removal.

[so called]

My colleague has accidentally allowed his glider plane trailer to come into contact with the dehumidifier material in his garage which contains Chloride.
He now has quite a large area of corrosion on the sub frame.

From looking on the internet, it looks like mechanical removal is the only way but the question is, is their a neutralizer he can apply before hand ?
The reason is that he doesn't want to get a wire brush on the area if all he will be doing is spreaging chloride crystals over unaffected areas of the chassis.

Would applying a die-electric chromate free paste, for example, act as a neutralizer ?

Thanks.

[so called]

Yes, not quite what I had in mind but an interesting tip when dealing with a pesky Audi.