Catalytic potential of low-cost natural zeolite and influence of various pretreatments of biomass on pyro-oil up-gradation during co-pyrolysis with scrap rubber tires

• Published in: Energy (Oxford) Vol. 238; p. 121820
• Main Authors: Khan, Shoaib Raza, Zeeshan, Muhammad
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.01.2022; Elsevier BV
• Subjects: Acid pre-treatment; Aromatic compounds; Aromatic hydrocarbons; Catalysts; Catalytic co-pyrolysis; Deoxygenation; Levoglucosan; Low cost; Natural zeolite catalyst; Oil; Physical characteristics; Physical properties; Pretreatment; Pyrolysis; Rubber; Scrap; Tires; Torrefaction; Zeolites; Aromatic hydrocarbons; Torrefaction; Catalytic co-pyrolysis; Acid pre-treatment; Natural zeolite catalyst
• ISSN: 0360-5442; 1873-6785
• DOI: 10.1016/j.energy.2021.121820

This study investigates the influence of low-cost natural zeolite (NZ) catalyst, metallic content and various pretreatments of rice straw (RS) on quality and quantity of oil derived from co-pyrolysis and catalytic co-pyrolysis of RS and scrap rubber tire (SRT). Oil obtained from co-pyrolysis of combined acid-washed and torrefied RS (WT-RS) and SRT (WT-RS/SRT) had 41% less oxygenates, 17% more hydrocarbons (HCs) and a significant amount of levoglucosan compared to the combination of raw RS and SRT (R-RS/SRT). Besides, char from WT-RS/SRT combination had more HHV (30.15 MJ/kg) than that of R-RS/SRT combination (26.85 MJ/kg). NZ incorporation into co-pyrolysis enhanced deoxygenation by 34% for catalytic combination of R-RS/SRT/NZ than non-catalytic co-pyrolysis of R-RS/SRT combination whilst the combination of WT-RS/SRT/NZ encountered 77.27%, 61.53% and 65.51% more deoxygenation than R-RS/SRT, WT-RS/SRT and R-RS/SRT/NZ combinations, respectively. An increase in HCs was found to be 40% and 31.25% for WT-RS/SRT/NZ contrary to WT-RS/SRT and R-RS/SRT/NZ, respectively. Additionally, 69.23% more mono aromatics along with more valuable gaseous composition were obtained in WT-RS/SRT/NZ than R-RS/SRT/NZ. HHV and physical characteristics of oil were superior for WT-RS/SRT/NZ. Results showed co-pyrolysis of pretreated RS-SRT as an effective route to improve product quality, which was further improved by the catalyst incorporation. [Display omitted] •Synergy among raw/treated rice straw (RS) and scrap rubber tire (SRT) was studied.•Combined washed-torrefied RS and SRT co-pyrolysis (WT-RS/SRT) was superior to all.•Oil of WT-RS/SRT had 41% less oxygenates and 17% more HCs than that of raw RS/SRT.•Catalyst addition to WT-RS/SRT had 65.5% more deoxygenation than WT-RS/SRT alone.•Mono aromatics selectivity of catalyst was highest (66%) for WT-RS/SRT among others.