China Petroleum and Chemical Corp, or Sinopec, has donated 140 million yuan ($20.5 million) in the past 10 years to help cataract patients with eye surgery in Xinjiang.

The world's biggest refiner set up a mobile hospital called the Sinopec Lifeline Express, an eye surgery training complex and 16 therapeutic centers for cataracts.

Serving as a mobile ophthalmic hospital, the lifeline express has traveled to 18 outlying areas including the Xinjiang Uygur autonomous region, the Tibet autonomous region, Qinghai province and Sichuan province. It has provided free medical care to over 38,000 cataract patients.