Just make sure to do something about NOx emissions, the cause of the downfall of Diesel in many countries. As long as you burn just about any fuel - hydrocarbon

Just make sure to do something about NOx emissions, the cause of the downfall of Diesel in many countries. As long as you burn just about any fuel - hydrocarbon or otherwise - using air you'll end up with NOx as a combustion by-product. Filtering out nitrogen from air is possible - zeolites are used for this purpose in oxygen concentrators - but hard to do at a high enough capacity to satisfy the needs of even modest-sized ICEs so a post-combustion NOx capture/conversion step will be needed regardless of the provenance of the fuel [1]. [1] http://www.meca.org/technology/technology-details?id=5&name=Catalytic%20Converters http://www.meca.org/technology/technology-details?id=5&name=...