Thanks for the reply, yes I am aware of biochar but wasn't sure grass was a suitable source.
The latest research seems to show that done properly, biochar can improve crop yields substantially, so that could be a way to pay for the process, but the other aspect is that it can be produced in a very low-tech manner, which is almost certainly the situation in many or most parts of the world.
How are you planning 'geological carbon dioxide sequestration'? I'm not sure of the chemistry/process, but is burning the charcoal completely actually necessary to produce hydrogen? It seems not, to me. The cynical view of course is that you will omit the costly sequestration step, which makes this just another biofuel endeavor, with the attendant pros, and, mainly (IMHO), cons...
The latest research seems to show that done properly, biochar can improve crop yields substantially, so that could be a way to pay for the process, but the other aspect is that it can be produced in a very low-tech manner, which is almost certainly the situation in many or most parts of the world.
How are you planning 'geological carbon dioxide sequestration'? I'm not sure of the chemistry/process, but is burning the charcoal completely actually necessary to produce hydrogen? It seems not, to me. The cynical view of course is that you will omit the costly sequestration step, which makes this just another biofuel endeavor, with the attendant pros, and, mainly (IMHO), cons...