The Evaluation of Mesoporous Materials as Catalyst in Fast Pyrolysis of Wheat Straw

Abstract

In this study, wheat straw was chosen as a biomass sample and the fast pyrolysis of this sample was carried out with or without catalyst at different conditions in a well-swept fixed-bed reactor. Experiments were carried out in a well-swept tubular fixed-bed reactor with a heating rate of 300 • C/min, between pyrolysis temperature ranges 300-800 • C in the nitrogen atmosphere. The results indicated that a maximum oil yield of 31.9% was obtained at a pyrolysis temperature of 500 • C in non-catalytic procedure. Siliceous and Al-MCM-41 materials were evaluated as potential catalysts in the pyrolysis experiments. Mesoporous materials have large pore dimensions with strong acid sites. These acidic sites catalyze some reactions in pyrolysis. The product yields and the quality of bio-oil were influenced with using MCM-41 materials. The bio-oil yield was reduced, whereas the gas yield increased with using a catalyst in the experiments. An increase in the fractions of pure phenol, alkyl phenols, alkenes+alkanes, carbonyls, aromatic, and cyclic compounds and a decrease in the fractions of methoxy phenols, acids+esters, furans, and alcohols were observed in the presence of Al-MCM-41 material. According to all results, the use of Al-MCM-41 materials as catalyst in the pyrolysis can be suggested to obtain both quality fuels and valuable chemicals.

Comprehensive Assessment of Particle-Scale Modeling for Biomass Pyrolysis: One-Dimensional versus Three-Dimensional Models

“…Char and volatile yields for the different reactor temperatures after pyrolysis has finalized: experimental and literature − (crosses), calculated (circles), volatile (pink and red), and char (black and blue).…”

Performance of mesoporous HZSM-5 and Silicalite-1 coated mesoporous HZSM-5 catalysts for deoxygenation of straw fast pyrolysis vapors

“…Esters (EST) and methoxy-phenols (MPH) contained four members, respectively, while alcohols (ALC), sugars (SUG), acids (AC) and phenols (PH) contained 1-2 group members. PH and MPH are attributed to the decomposition of the lignin component of wheat straw, while anhydrosugars and smaller oxygenates result from the pyrolysis of hemicellulose and cellulose [60][61][62].…”

Waste to liquid fuels: potency, progress and challenges

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