Thermal degradation of cellulosic materials

Abstract

Fortisan, cellulose triacetate, and NOroxidized cellulose were pyrolyzed in a vacuum in the temperature range 180 0 to 465 0 C. Cotton cellulose and cellulose t ri acetate were also pyrolyzed in nitrogen at atmospheric pressure. The tar yields were in the decreasing order from: Cotton, Fortisan, cell ulose triacetate, and oxidized cellulose. The other volatiles consisted mainly of acetic acid, carbon dioxide, and carbon monoxide, from the triacctate; and water, carbon dioxide, and carbon monoxide from the other celluloses. In all cases there was a carbonaceous residue (volatilization end point), the amount depending on t he natur e of the cellulose and the temperature of pyrolysis. When pyrolyzed in nitrogen at atmospheric pressure, cotton cellulose and cellulose triacetate yielded less tar than when pyrolyzed in a vacuum. T he tar from cellulose triacetate consisted of a compound whose infrared spectrum resembled that of the original triacetate. Cotton cellulose, Fortisan, and cellulose triacetate do not differ much in t heir initial rates and activation energies of thermal degradation. Oxidized cellulose has very high initial rates of therm al degra dation .