Originally Posted by
CPRich
starting with 1543:
Whoever falsely makes, forges, counterfeits, mutilates, or alters any passport or instrument purporting to be a passport, with intent that the same may be used; or
Looks like you'd max out at 10 years

I'm not sure if removing the visa sticker would count as altering the passport itself. FWIW, I can attest to the fact that Chinese visa stickers have a tendency to start peeling off.
Also, the "mutilates" part would seem to be so broad as to cover the unfortunate sap who ran his passport through the wash or spilled some coffee.
I'd be far more afraid of having trouble with an immigration or consular official who notices and decides the passport should be considered invalid than of any real punishment beyond being forced to cough up for a new one. Still, likely not worth the risk.