Copyrolysis Behavior of Xylan and Polyvinyl Chloride Plastic

Copyrolysis behaviors of xylan and polyvinyl chloride (PVC) with different mass ratios were experimentally investigated via thermogravimetric analysis and a fixed-bed reactor. Several species of pyrolysis products were detected through Py-GC/MS. Differential thermography results of the mixtures showed obvious deviations, indicating synergistic effects to promote the reaction to occur at a lower temperature but a slower rate, in ranges of 4-39 degrees C and 0.42-9.68%/min, respectively. The fixed-bed experiments indicated that the interaction could promote char yields by 1.1 to 6.4% and reduce oil yields by 0.2 to 2.9%. The activation energy (E) of mixtures showed a deviation compared with the calculated values, in a range of 13.7-26.2 kJ/mol, indicating interactions to promote the occurrence of copyrolysis. Through the Py-GC/MS results, the synergistic effect was observed to reduce the aromatic components by 2.05 to 15.53% and increase oxygenated compounds in a range of 0.29 to 16.91%. One compound named dl-2-ethylhexyl chloroformate was detected in oil of the mixture, accounting for 5.93% of the products. The addition of PVC could convert the aldehyde and ketone to the alcohol through the nucleophilic addition reaction of the carbonyl.