Sorry, but I don't think so. We get this question often on this board, and no one ever has a good answer. I know some sort of gelling agent is used to make naval jelly -- that's phosphoric acid in what I assume is some sort of organic gel, or maybe polysiloxanes is better. But phosphoric acid is a weak acid. People who want to gel con. sulfuric, or oxidizing acids may simply be out of luck. There's also hydrated silica gels, but once you've added a very hydrated silica gel to concentrated sulfuric ... you don't have concentrated sulfuric anymore.