I wouldn't recommend that. Ask for someone who is responsible for the chemical waste. Normally it is handle separated.

Depending on the regulations in your lab, but it should normally be kept in a close/separate container with clear labeling of used oil. they normally sent for either incineration or recycling facilities

Thank you Tien, Amin and Yahia

I'll refer to our department regulation!

http://www.siliconerecycling.com/recycling-of-silicone-transformer-oil/