Cellulose pyrolysis kinetics: An historical review on the existence and role of intermediate active cellulose

Cellulose pyrolysis, studied since more than one century, has been the object of a great number of papers. Several related kinetic models have been established in large experimental conditions, from slow to fast pyrolysis. Unfortunately, no actual consensus is reached. The primary formation of intermediate species accompanied or not with phase change phenomena are amongst the main matters of concerns. The purpose of the present review is to report the controversies, well-established knowledges and unresolved questions concerning the existence and role of intermediate species (often called “active cellulose”). After a general discussion, a few research topics are suggested at the end of the paper.