Yes, in the given facts, refund of accumulated Input Tax Credit (ITC) is admissible, subject to statutory conditions.
You are procuring goods on payment of GST at 18% and supplying the same at a concessional rate of 0.1% to exporters under Notification No. 40/2017-Central Tax (Rate). This results in accumulation of ITC due to a higher rate of tax on inputs as compared to output supplies.
As per Section 54(3) of the CGST Act, 2017, refund of unutilized ITC is permissible in cases of inverted duty structure, i.e., where the rate of tax on inputs exceeds the rate on output supplies. Your case squarely falls within this category.
Further, Circular No. 125/44/2019-GST prescribes the procedural framework for filing refund applications, including documentation, timelines, and the manner of filing Form GST RFD-01. The said circular supports the processing of such refund claims but does not independently determine eligibility, which is governed by the Act and relevant notifications.
It is pertinent to ensure that the goods in question are not covered under the restriction specified in Notification No. 5/2017-Central Tax (Rate), as refund of ITC is not allowed in respect of notified goods under the inverted duty structure.
Subject to the above condition and proper compliance with Rule 89(5) of the CGST Rules regarding computation, your claim for refund of accumulated ITC is legally tenable.