Yes, but ideally you'd want the most adhesive substance you could find...the aDsorption power of the activated charcoal/carbon has got to be greater than that of any oil. One would think, anyway.
More bang for your buck as well. The activated charcoal thickens very fast in the mouth, which, by OP logic, means it pulls toxins verrry fast, yes? Whereas the oils that people use thin, then thicken, then thin, etc.