Propane works but there are serious hazards with it due to the pressure. If you try to release it from a valve, it looks like a flame thrower, not exactly like an explosion.
For the real movie type explosions, you need benzoyl peroxide with a fuel moderator. In large quantites, it will detonate so you add a fuel like oil to slow it down. These are expensive FX and used only for simulation of grenade-sized explosions and smaller and inside a set/building where blast overpressure is to be avoided, after all, the crew needs to survive.
Good luck on finding it in the quantities you need. Its available but the shit is some serious hazmat and needs to be kept wet until needed, then you dry it and mix.
Real explosions with high explosives are not that spectacular unless you add fuel. IIRC, bomb simulators for some special effects are gasoline in bags over a small quantity of high explosive. They are frequently assembled in cardboard boxes to guide the fuel into the desired cloud. The gasoline burns on the outside of the resultant cloud, making a fireball of considerable duration. This is ONLY DONE OUTSIDE for obivious reasons. Never even think about doing it with Tannerite inside a building.