Hey there. I've had what I'm pretty sure were squeaky pedals for a while now, and just went to REI and bought Pedro's Bike grease for the purpose of lubing them up, hopefully eliminating the squeaking. I'm not sure what the name of the pedal manufacturer is, but they are platform pedals that just slide onto the spindle when you remove the cap. When I removed one of them, a bunch of either dirt, dry grease, or maybe rust came out of the pedal and off the spindle. I think that this is a good suggestion that I should clean the inside of the pedals and spindles before applying new grease.

What should I use to clean them? I am currently in a chemistry lab, so all solvents (toluene, petroleum ether, hexanes), ethanol, isopropyl alcohol, and acetic acid are all available to me.

If they're cheapies, bin them. Bearing surfaces will not be healthy. If they're not cheapies there may be a rebuild kit available.

If you're a cheapie, squirt them out with WD40 and pack them with waterproof Teflon grease. Or Pedros, whatever that is.

Avoid the toluene, ethanol, petroleum, ether etc. They can be habit forming.