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    I have just read through your site which is quite good. Hopefully you will be able to help me out a bit. At work we are trying to remove silicon off aluminium as the aluminium needs to be painted but so far nothing seems effective, not even acitone. Scrapping is slow and not always removing the silicon.
Hope to hear from you soon
Thanks

Your question is a good one.  Silicon is well known for its chemical inertness, (ie. it tends to not react with many other chemicals).  Depending on what type of silicon your dealing with, this may or may not be easy to solve. If the silicon is from a lubricant, it's probably the graphitic form which is soluble in a strong combination of nitric and hydrofluoric acids, neither of which I would recommend for you to use...and hydroflouric acid is not easy to come by.   If it's silicon from an acidic form (probably any other form other than a lubricant), you should try ammonia.  In either case, leave your acetone at home...it will NEVER work!

Thank you very much for taking the time to reply to my email. My boss was quite impressed. Your solution was ideal and we got stuck into the job and was then able to have the machinery painted with no problems.We have been preparing the factory for some visitors hoping to get a contract with them, they are due tomorrow.