Water raised to the temperatures at which these pyrolysis events take place is in a supercritical state and thus under these conditions is an oxidant of organic species, both toxic and non toxic. The water is reduced to hydrogen gas and carbon oxides, basically syn gas, presumably with a residue, depending on conditions, or pyrolytic carbon, itself a valuable material.
I was unfamiliar with the claim about potassium additives converting pyrolytic carbon into slow release phosphates, but I will get around to calling up the reference.
This review did not explicitly cover the issue of pyrolytic gases, but these are of significant value as well. There are many papers discussing this topic.
My ideas on nuclear energy are designed to make use of the high temperatures at which fission occurs, connected to a large heat network. The supercritical water/pyrolytic system could be a side product, or rather an additional product, of that heat network, with the production of electricity also being a side product.
The issue is to close the carbon waste cycle, and the chemical waste cycle while providing clean water and clean air.
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