extracting/concentrating citric acid from citrus juice

[cipher510]

how would this be done without using a powerful acid?

[powerlabs]

You could concentrate it via extraction with alcohol, but why would you want to? Ebay sells it at $6/pound. The alcohol you'd need to extract a pound would cost many times that.

[cipher510]

thankyou.
i was restoring an old minibike and was looking for a cheep way to remove a heavy coating of rust from the frame.
i would up using .69 cent sand paper and a lot of time xD