See both are completely different. You should be choosing on the basis of your interest. If you are interested in flying and all aero space related things then aeronautical engineering is best for you. 

But if you have an affinity for chemistry then go for chemical engineering. Chemical being one of the oldest branch. It comes with great number of opportunities. But when you talk about aeronautical engineering then there is not much offer in India when compared to other developed countries. But it is becoming popular day by day. 

So if you want quick placement. Go for chemical engineering. Else aeronautical engineering.

Thanks