Yes. The generic RBOB types are as follows: "Any oxygenate," "Any renewable oxygenate," "Any ether," "Any renewable ether," and "Non-VOC controlled renewable ether only." There are several legal oxygenates which may be blended with the various types of RBOB. Please refer to the RFG and renewable oxygenate regulation preambles for a detailed discussion.
For example, it would be appropriate to blend ethanol with "any oxygenate" or "any renewable oxygenate" RBOB, but inappropriate to blend ethanol with "Any ether" or "Any renewable ether" or "Non-VOC controlled renewable ether only" RBOBs. MTBE may appropriately be blended with "any oxygenate," "ether only," (and if the MTBE is from a renewable source "Any renewable oxygenate" or "Non-VOC controlled renewable ether only" RBOB).(8/29/94)
This question and answer was posted at Consolidated List of Reformulated Gasoline and Anti-Dumping Questions and Answers: July 1, 1994 through November 10, 1997 (PDF)(333 pp, 18.17 MB, EPA420-R-03-009, July 2003, About PDF)