There is a large variety of H2S scavengers. Depending on the application is the scavenger. Some might even be considered non-reversible reactions, i.e. hotlime (CaO) in drilling fluids.
Something you might want to look into is the basic chemistry of the reaction, whether it is exo or endo thermal and start there by determining the possibility of reversion due to temperature. As well, you might want to see what is boiling and how these gases might affect the products of the scavenger reaction.
What is your scavenger? What will be the product? How is the reaction taking place? Ask this and you might have an answer