Try an experiment with a small amount; put it in hot water, very hot such as near boiling point.
I expect that the water will separate the oil from the carbide dust and float the oil to the surface while the dust sinks. You may need to mix it vigorously for a while then let it stand and settle.
At least this is the way the crude oil is separated from the sand in the big tar sands oil recovery operation in Alberta.
Then your only problem is separating the oil from the water; which is not too difficult.
An open mind is a virtue...so long as all the common sense has not leaked out.