Yes. Conflicts of interest would be sure to arise, and something within the scope of "high crimes and misdemeanors" would be found to justify his removal from office.
If he's already burned his bridges with Congress, the necessary 2/3s of each House will be easy to obtain.
And all it takes is a simple majority of Congress, or of the (Executive branch) Department heads, to set this in motion.
It's like an impeachment, except the President immediately is stripped of power. If Congress then finds him fit, then the power is returned.