JUDGMENT

S.B. Majmudar, J.-These six appeals are preferred by the common appellant, M/s Gujarat State Fertilisers Company, against the central excise authorities, being aggrieved by common judgment and order dated 19.4.1991 rendered by the Customs and Gold (Control) Appellate Tribunal ( CEGAT for short). The appellant contends that it is entitled to concessional rate of excise duty on raw naphtha consumed by it at its factory at Vadodara for manufacturing ammonia which was captively consumed for manufacturing molten urea. That claim for concessional rate of duty is based on Notification No. 75 of 1984 dated 1.3.1984, as amended from time to time, issued by the Central Government in exercise of its powers conferred by sub-rule (1) of Rule 8 of the Central Excise Rules, 1944 promulgated under the Central Excises and Salt Act, 1944. The appellant also claimed total exemption from excise duty on the manufactured ammonia utilised by it for production of molten urea by captively consuming the aforesaid ammonia manufactured out of raw naphtha. The said claim is based on a similar exemption notification issued by the Central Government being Notification No. 40 of 1985 dated 17.3.1985, as