Biotechnology Forums

Can a plant be engineered to absorb hydrogen from minerals in soil and release it as a hydrogen gas byproduct

It depends upon your perception of plants. If you consider Algae as plants, then yes it has already been achieved on a small scale. Even microbial Fuel Cells are able to achieve it to variable degree of volume. But this is an active area of research (not only on production front but management as well). So, all the best if you have some plans to work in this direction.
As far as engineering the plants to do so, is concerned, nothing is impossible. But, I hope you understand, genetic modification requires years of research and testing. People spend their entire career on a single goal which might propagate for generations...