Co-upgrading of biomass and polyethylene -derived volatiles for organic liquid over Ru, Ti, Sn/HZSM-5 coupled with NTP technology

Abstract

Co-upgrading of biomass and polyethylene -derived volatiles was conducted over HZSM-5 and its metal-modified versions, and NTP was introduced to enhance the conversion. The effects of metal species on the active radicals, organic yields, properties and compositions were explored. The Ru and Ti species, especially the low-valence titanium-oxides, increased atomic radicals, relieved the bottleneck of hydrogen transfer, and induced more volatiles into the radicals scale. The synergy of acid sites, metal species and NTP contributed to the integration of volatiles and exhibited promising potential in lowering oxygen and increasing organic yield. Specifically, TiHZ5 yielded the organic liquid of 58.73 % with the HHV of 38.73 MJ/kg, and RuHZ5 produced 51.70 % of organic liquid with the HHV of 36.96 MJ/kg. The synergy between SnHZ5 and NTP was so weak that it sacrificed partial yield to promote HHV. The Ru, Ti, and Sn modification increased the aromatic selectivity from 23.38 %–48.9 %, 72.14 % and 35.66 %, respectively, which caused the decrease of effective hydrogen to carbon ratios. Particularly, TiHZ5 gave the maximum MAHs selectivity of 64.19 % and minimum PAHs selectivity of 7.95 %. Besides, Ru, Ti and Sn modification decreased coking rate from 16.97 % to 7.04 %, 4.62 % and 8.46 %, respectively, and removal of coke became easier. This study provided a new waste-energy refinery way to reduce the disposal of waste plastics and relieve the dependence of fossil fuels.