China's largest oil trading firm, UNIPEC has taken over the marketing of Ghana's share of crude Oil from the Jubilee field.JOYBUSINESS has learnt the firm took over the role from January this year.This was after the Ghana National Petroleum Company decided not to review its contract with Vitol and Woodfields which ended last year.UNIPEC is expected to market Ghana's crude for the next fifteen and half years.Joy Business sources say UNIPEC has taken over as part of conditions covering the recent 3 billion Chinese loan.UNIPEC is a subsidiary of SINOPEC, the firm constructing the 700 million dollars gas processing plant in the western region.