24 hours of Transit Without Visa for India Passport

I am holding India passport, returning from USA. I am flying from Houston to Mumbai via Beijing.

I will be arriving in Beijing on 04th November 2017 early morning 5:30 am local time & my connecting flight to Mumbai same day at 19:40 pm.

Since it is more then 12 hours of transit time, I am planning to visit Great Wall of China, hence I wanted to get clarification on below points.

Will I be eligible for standard 24 hours direct transit?
OR do I have to apply for it from India itself.

Your assistance is highly appreciated, waiting for your revert.