You need a pressure ratio of 1.8:1 to get the velocities you need to achieve mach one, which is what a typical media blaster will operate at. Actually, you'll just get to mach 1 and then you'll create a normal shock that will drastically reduce the velocty and pressure of the flow, but that will happen at the exit of the nozzle of the media blaster (hence the loud noise when you vent high pressure air).
However, as long as you introduce the soda into the stream before you exit the tube (end of the media blaster), then you will accelerate your soda to a very high velocity. I believe mach 1 is about 650 mph at sea level, although the conditions inside the media blaster will be much higher pressure and lower temp. Those two changes might balance out, so you could see 650 mph air velocity inside the media blaster before it shocks and loses velocity and pressure. That is much higher than the 200 mph you'll get from your leaf blower. Remember, "Kinetic Energy" = 1/2*Mass*Velocity^2, so velocity plays a large role in the effect of media blasting.
You would need a leaf blower with a high pressure ratio capability to achieve the same results, but I don't think the engine or the fan are designed for that. Best bet is to use a proper media blaster with sufficient flow and pressure.
FYI, if you release air above 26 psi in direct sunlight (i.e. air from a tire, liquid air in a can, compressor air), and hold the air source close to where a shaddow can be cast, then you'll see the shock waves in the shaddow since their formation alters the direction of incomming light.
Camelman