Enhanced production of naphtha-range compounds from arundo donax via catalytic fast pyrolysis using SAPO-11

Abstract

Arundo donax, acknowledged for its elevated energy content, substantial biomass yield and rapid growth, stands as an alluring candidate for biofuel production. In this investigation, a molecular sieve-based catalyst was utilized to scrutinize the catalytic fast pyrolysis (CFP) of Arundo donax, aiming for the production of naphtha-range compounds. The study also encompassed the evaluation of pyrolysis product yields within a fixed-bed reactor. The systematic exploration included an assessment of the impacts arising from catalyst type, temperature, weight hourly space velocity (WHSV), and N2 flow rate. The results demonstrated that at 500 °C, WHSV of 1 h−1 and N2 flow rate of 300 ml/min, SAPO-11 exhibited a selectivity of 64.55% to naphtha-range compounds and 64.55% to isomerous naphtha-range compounds. This was in stark contrast to the control group, which contained no catalyst (with a selectivity of 41.40% and 3.19%, respectively), SAPO-41 (with a selectivity of 11.02% and 9.55%, respectively) and HZSM-5 (with a selectivity of 59.89% and 53.51%, respectively). Additionally, SAPO-11 yielded the highest bio-oil compared to other catalysts (SAPO-11 of 28.52 wt% > none of 19.48 wt% > HZSM-5 of 18.90 wt% > SAPO-41 of 13.11 wt%). The conclusions drawn from these findings imply that the synthesized SAPO-11 catalyst exhibited superior catalytic activity and isomerization proficiency in contrast to other catalysts (SAPO-41 and HZSM-5). Remarkably, under the specified conditions of SAPO-11 catalyst, temperature = 500 °C, WHSV = 1 h−1 and N2 flow rate = 200 ml/min, the CFP process yielded a remarkable maximum absolute yield of the naphtha-range compound at 25.82 wt%, with an isomerized naphtha-range compound absolute yield of 25.35 wt%.