( 1 ). The appellants manufacture liquid pure carbon dioxide for use in soft drinks, fire extinguishers and other industrial uses. The appellants filed a classification list on 23/3/1978 claiming exemption from the payment of excise duty in respect of carbon dioxide manufactured and cleared by them on the basis of Notification No. 71 of 1978 dated 1/3/1978 under which full exemption was granted up to an aggregate value not exceeding rupees five lakhs, in respect of certain goods specified in the said Notification which were cleared on or after 1st April of any financial year. Carbon dioxide is one of the commodities mentioned in the Notification.

( 2 ). The classification list filed by the appellants was kept pending and was not approved by the Assistant Collector of Customs since there was a dispute as to whether the appellants were to be considered as the manufacturers of the goods or whether Coromandal Fertilizers Ltd. were the manufacturers. Ultimately an order was passed in favour of the appellants by the government of India being Revision Order No. 939 of 1979 dated 30-10- 1979. In the meanwhile, on 5/7/1979 the Superintendent of central Excise informed the appellants that they were eligible for exemption under the said notification. The appellants who had, in the meanwhile, cleared their goods on payment of duty, filed a refund claim on 4/1/1980 in respect of the duty paid by them from 1/4/1978 to 25/7/1978. After the filing of the refund claim, the classification list of 23/3/1978 was finally approved with effect from 1/4/1978 on 24/4/1980.

( 3 ). The claim of the appellants for refund was rejected as time-barred by the Assistant Collector in view of Rule 11 of the central Excise Rules, 1944. On an appeal, the Collector (Appeals) by his order dated 4/8/1981 upheld the order of the Assistant Collector. On further appeal to the central Excise and Gold Control Appellate tribunal (CEGAT), the CEGAT rejected the appeal of the appellants by its order dated 24/4/1987 upholding the contention of the Department that the refund claim having been filed beyond the period of six months from the date of payment of duty, it was barred by limitation under Rule 11 of the central Excise Rules, 1944.

( 4 ). The appellants filed a writ petition being No. 2155 of 1988 before the a. P. High court challenging the above order of CEGAT. In the said petition, the appellant had also challenged the vires of Section 11-B of the central Excises and Salt Act which was introduced by the Amending Act 40 of 1991. The High court by its order dated 29/4/1993 dismissed the saidwrit petition along with a group of other writ petitions. The present appeal arises from the above judgment of the High court.

( 5 ). The question of vires of Section 11-B is now settled by a decision of this court in Mafatlal Industries Ltd. v. Union of India. The appellants however, contend that their claim for refund was not time-barred inasmuch as on the date when they filed the claim for refund their classification list had not been approved. All payments made pending the approval of the classification list can only be provisional payments. Hence their claim for refund which was made even prior to the approval of the classification list cannot be considered as time-barred under Rule 11. The period provided by rule 11 would run only from the date of approval of the classification list. The appellants have relied upon a decision of this court in Samrat international (P) Ltd. v. CCE where this court said that limitation under rule 11 commences only from the date of final assessment. On the facts of that case, however, this court had held that the payment of duty which was made by the appellants in that case was provisional and the procedure under rule 9-B had been followed. We have not been shown any material on record to indicate whether the appellants in the present case had cleared carbon dioxide manufactured by them by following the procedure laid down in Rule 9-B or that the