How high does a material (say, a piece of cloth, or wood, or whatever) temperature have to reach before it can begin emitting CO? Can it be generated merely by being heated, but not actually combusting yet?
Here is a source that says gasification of biomass starts at about 600 degC.
Gasification is the phase where you get CO (AIUI). There is also pyrolysis, which is a process that starts at lower temperatures but does not yet generate CO. And yes, both of these processes involve “merely” heating the material (with no oxygen present).
600 degC would be the minimum gasification temperature, according to that source. Industrially, and practically, you would want to use temperatures higher than that to get optimal yield of syngas.
CO production from carbonaceous materials due to heating depend on the composition of the material, the presence of air (oxygen), the presence of water (moisture) and the *of heating *.
In general this temperature band is between 100 to 500 C. Cite : Pyrolysis - Wikipedia
There are also combustibles like low rank coal which show spontaneous combustion at room temperature when dried. They generate CO which helps in combustion.
On reviewing , it should be * Rate if heating *. When we did our pyrolysis experiments, the product composition depended on the temperature and how quickly we got to that temperature. So if you heated a pieces of wood to 500 F at 100 F per min or 50 F per min played a role. This is because of reaction kinetics and heat conduction inside the material.