Improving hydrocarbons production via catalytic co-pyrolysis of torrefied-biomass with plastics and dual catalytic pyrolysis

To increase the low yield and selectivity of aromatic hydrocarbons during the biomass pyrolysis process,we torrefied the biomass and then co-pyrolyzing with plastics such as high-density polyethylene(HDPE),polystyrene(PS),ethylene-vinyl acetate(EVA) and polypropylene(PP) and also single and dual catalyst layouts were investigated by Py-GC/MS.The results showed that non-catalytic fast pyrolysis(CFP) of raw bagasse(RBG) generated no aromatics.After torrefaction non-CFP of torrefied bagasse(TBG) generated low aromatic yield.Indicating that torrefaction would enhance the proportion of aromatics during the pyrolysis process.The CFP of TBG200℃and TBG240℃over ZSM-5 produced the total aromatic yield of 1.96 and 1.88 times higher,respectively,compared to non-CFP of TBG.Furthermore,the addition of plastic could increase H/Ceff ratio of the mixture,consequently,increase the yield of aromatic compounds.Among the various torrefied-bagasse/plastic mixtures,the CFP of TBG/EVA(7:3 ratio) mixture generated the highest the total aromatic yield of 7.7 times more than the CFP of TBG alone.The dual catalyst layout could enhance the yield of aromatics hydrocarbons.The dual-catalytic co-pyrolysis of TBG200℃/plastic(1:1) ratio over USY(ultra-stable Y zeolite)/ZSM-5,improved the total aromatics yield by 4.33 times more than the catalytic pyrolysis of TBG200℃alone over ZSM-5 catalyst.The above results showed that the yield and selectivities of light aromatic hydrocarbons can be improved via catalytic co-pyrolysis and dual catalytic co-pyrolysis of torrefied-biomass with plastics.