What's the difference between China United Oil and China Oil?

There are differences. China United Petroleum Co., Ltd. is an oil foreign trade company jointly funded by China Petroleum and Natural Gas Group Corporation and China Chemical Import and Export Corporation. China Petrochemical Company is a super-large petrochemical enterprise group reorganized by the state on the basis of the former sinopec group in July 2006, 1998. It is a state-owned company wholly owned by the state, an institution authorized by the state to invest and a state holding company. Therefore, there is a difference between the two.