I think that we need a good explanation of what is a black hole and how it forms...
Let's start from the beginning.
Black holes form from very dense stars, much bigger than our sun. When the hydrogen in the core of a star finishes, the energy become less and the core collapse and become more dense, the pressure rise the temperature again and the elium starts to burn like idrogen before creating carbon. When the elium finishes again, the energy emitted become less and the gravity make the carbon core collapse again, starting a new reaction with the carbon that creates neon. The star then is like an onion with different strates. From hydrogen at the surface to the neon in the core. The process reapeats again neon becomes oxigen, oxigen becomes silicium and silicium becomes iron.
Here start the problems. Unlike the previous elements the fusion of the iron requires more energy than the process creates, so the gravity "win" and the core suffers a final collapse: the outer part of the star explodes and all the elements created are shoot in the space (this elements in the future may form other stars and planets, and maybe life). The core collapses more and more, untill it reaches a critical density, so big than even light can't escape: a black hole is created. All the remaining matter of the star falls into the events' horizon and (probably) become a superdense degenerated matter: the atoms are destroyed, and also neutrons and protons are split into quark up and down. These particles are than pressed into a singularity, a point with no dimentions and with infinite density and heath. This is why can't be a reaction similar to the one into the star core into a black hole. Simply there aren't atoms. By the way even if the reaction was there, the products of it could never escape from the events' horizon. What happens into a black hole cannot influence the universe out of that border.
If nothing can escape, why the black hole emits radiation like x-ray?
The answer must be found into the quantistic theory. (This is not a part that I know very well, so it could be wrong).
In the vacuum, everywhere in the universe, a couple of particles are created, one of matter and one of antimatter. After an infinitesimal time, they join and annihilate.
But what happens when the particles are created just near an events' horizon? One particle fall into the black hole, and the other escape at the speed of light. That's it. The x-ray emission is not created directly by the black hole, it doesn't come from the singularity. Nothing can escape a black hole.
Please tell me if this part is correct.