posted 10 years ago
Ok, firstly don't even think of burning the laminates. PTFE is Teflon and it gives off small amounts of octafluoroisobutylene when burned, which is an extremely toxic gas, actually banned by the U.N. chemical weapons treaty. It also, more importantly will contaminate your soil with dioxins which is currently one of the biggest pollution problems in world agriculture right now. Particularly in countries where they were dumped indiscriminately all over the countryside (like we did in vietnam). Basically don't ever burn chlorinated or fluorinated plastic... the amounts will be small with what you are doing, but still, don't do it.
As far as regular printer paper, the paper itself is mostly tree fiber and clay and isn't particularly toxic... but it burns like total shit in large quantities so good luck making it do anything besides burn the outside of the stack.
As far as the ink, ink jet printer ink is alcohol based and not particularly toxic, whether it becomes that way when burned, I'm not sure, it doesn't really matter though because this is kind of stupid for other reasons. Namely that wood, what everyone else uses to make biochar is totally free. If you want charcoal then it is much easier to gather some fallen logs from a nearby forest. It is easier than your plan, and will yield infinitely more usable charcoal.