Pronunciation of "du 11 septembre 2001"?

Question

I would expect this to be pronounced "de l'onze septembre," despite being written with *du* instead of *de l'*.Is that correct? Is it only written this way because it's written with numerals?

Answer 1

It would still be pronounced like "du onze," with no liaison. Yes, "du' is the contracted preposition of "de le" for masculine words, but "du" is indeed a different word and therefore needs to be treated and pronounced as such. Again, there is no liaison, so it isn't "d'onze." Just pronounce "du" and then "onze" separately.