I can't give you the page number, but I can tell you that the first mention of Aouda occurs in chapter 12. However, we don't learn her name until chapter 13, when Phileas Fogg and Passepartout rescue her from being burned alive with her dead husband.
Since the book was first published in 1873, many, many editions have been printed in many, many formats. In order for someone to give you a page number, you need to indicate which edition you're using, who published it, when it was published, whether it is abridged or an illustrated classic--in other words, not an easy thing to do.
I hope this helps!