It's obvious that those firelighters make a lot of carbon particulates. Just burning one and looking at the flame, thick black smoke comes off it. I suspect t

It's obvious that those firelighters make a lot of carbon particulates. Just burning one and looking at the flame, thick black smoke comes off it. I suspect the cellulose is the cause, rather than the kerosene. Perhaps the problem is that the kerosene burns at a lower temperature than the cellulose, and liquid kerosene can act as a decent heatsink via the specific heat of vaporization, therefore preventing the cellulose getting hot enough to properly burn.