Another thing you could do is get a bench grinder with a protective shield to cover the grinder, yet has holes for both hands to go into, and grind away. After you're done grinding, if you have a magnet, you can pick up all of the pins, or at least 99%+ then discard the plastic.
If done that way, it'll be safer and cleaner, without and chemicals, nor the need to pull each pin out one at a time to get them done. On the other hand, depending on the connectors or pin components you're working with, you can take a screwdriver and split it lengthways and most of the pins will fall out within 10 seconds.
Kevin