Brainstorming - maybe this can suggest better answers?
I suspect there is no solution

, that you are only being asked to show some chemical knowledge and thinking. This wine is not so valuable that I can imagine an economically viable process for just removing one component. If there were I doubt you could satisfy the health authorities. Maybe destroying the diol is more important than recovering the rest, the object being to minimise the toxicity when you throw it into a river or waste system?

I do not have any very good text and cannot find anything much online I think at least the following is not worse than what has been suggested already.
Because of the vic
diol, borate forms a complex with glycol. You could add borate to the wine you distill and that should make the distillation much more specific. Distillation is not destroying the glycol - it's concentrating it.
Adding borate to a chromatography, e.g. ion exchange chromatography, should add specificity. I think borate used to be used in paper chromatography of ribonucleosides, which are glycols (contain -CHOH-CHOH-). However it makes sense to use the borate in immobilised forms, and there are boronate solid supports which are capable of giving very fine separations, even chiral separations - have a glance at these http://www.uni-graz.at/~schmidm/publications/JChrA761_269-275.pdf
http://books.google.it/books?id=kCl...X&oi=book_result&ct=result&resnum=3#PPA216,M1
It sounds too advanced to be the answer sought here, but useful glimpses if you are going into biochemistry.
About the only other well known thing that distinguishes diols from mono-alcohols is oxidation by periodate. See
http://www.mhhe.com/physsci/chemistry/carey/student/olc/ch15oxidativecleavagediols.html . You would have to know something about the conditions for that reaction, e.g. does it happen in fairly dilute aqueous solution? I don't know but I think it does.
Then maybe there exists now some immoblised enzyme system with suitable oxidant to specifically oxidise the glycol - the only small hope of being able to drink it afterwards. I am not recommending that.