The board of directors of Bongaigaon Refinery & Petrochemicals today approved the scheme of amalgamation for merger of the company with Indian Oil Corporation (IOC).According to a release issued by Bongaigaon to the BSE today, the board has recommended a share swap ratio of 4:37, i.e. Bongaigaon shareholders will be alloted 4 IOC shares in lieu of 37 shares held, as of the record date.The scheme is, however, subject to the approval from the government and all other consents or approvals from regulatory authorities or otherwise as may be required under Law, the release added.