Insight into impact of co-pyrolysis process parameters on cross-interaction of volatiles between furfural residue and coal via rapid infrared heating

The energy utilization of furfural residue is an effective way for the clean production and carbon emission reduction of the furfural industry. In this study, the co-pyrolysis behaviors and products distribution of furfural residue and long flame coal were investigated via TG-FTIR-GC/MS and infrared fast heating technique. According to the analysis of TG-FTIR-GC/MS, the functional groups of carbonyl, phenolic and alkyl were generated with the co-pyrolysis process. As the temperature rose from 500 to 800 °C, the yield of oil increased from 15.27 to 18.24 wt% before decreasing to 16.64 wt%. With the increase in heating rate, the yield of oil increased first from 18.24 to 20.90 wt% and then decreased to 16.70 wt% at 40 °C/s. RSM was employed to optimize the oil yield and the highest oil content of 21.73 wt% was obtained at 650 °C and 30 °C/s. The analysis of GC-MS shows that elevating the temperature and heating rate decreased the content of ketone, phenol, ether, and furan. In addition, the result of simulated distillation shows that the total content of light fractions of oil is between 71.86 % and 77.16 % at all co-pyrolysis conditions. The evolution of char structure was analyzed by Raman, EPR and BET. The higher temperature and heating rate promoted the deoxidation of char to form carbon-centered radicals and developed pore structures. The findings may yield useful insights into the synergistic mechanism of co-pyrolysis between long flame coal and furfural residue, thereby enhancing our comprehension and facilitating future commercial applications. •Co-pyrolysis synergistic effects of coal and furfural residue were analyzed systematically.•Higher temperatures promoted the cleavage of C-O, C-H and β-O-4 to produce radicals.•Co-pyrolysis enhanced oil yields up to 21.73 wt% with over 70 % light fractions.•Infrared fast heating developed pore structures promoting the deoxidation of char.