Characterization of carbonized material obtained by heat treating nitrile butadiene rubber pyrolysis residue

Chemical recycling of rubber waste has long been considered. Disposable rubber gloves could be appropriate as feedstock because separation from the metals is not required after pyrolysis. In this study, the feasibility of using the pyrolysis residue obtained by nitrile butadiene rubber glove liquefaction as a solid fuel was investigated. The calculated calorific value and chlorine content of the water-washed pyrolysis residue satisfied the quality standards for refuse paper and plastic fuel. Furthermore, the pyrolysis residue was heated in an inert gas atmosphere over 500 °C for 2 h. When the heating temperature was above 800 °C, the surface functional groups and the oxygen content were decreased significantly. In addition, the calculated calorific value of these heat-treated residues exceeded 20 MJ/kg. Therefore, although the quality of the solid fuel was lower than that of the waste tires, the heat-treated residues were comparable to the refuse-derived fuel obtained from combustible general waste. The hygroscopicity and surface hydrophobicity of the water-washed pyrolysis residue were decreased by heating above 800 °C. This result suggests that the water-washed pyrolysis residue heated above 800 °C exhibits superior storage and transportability.