Production of bio-oil and bio-char from pyrolysis of sawdust wood waste (SWW)

Abstract

This study deals with fast pyrolysis of sawdust wood waste (SWW) at the range of temperature 300–700 °C in a stainless steel tubular reactor. The aim was to experimentally investigate how the temperature, the particle size, the nitrogen flow rate (N2) and the heating rate affect bio-oil, bio-char and gaseous products. These parameters were varied in the ranges of 5–20 °C/min, below 0.1–1.5 mm and 20–200 mL min−1, respectively. It was concluded that both the temperature and heating rate have a significant effect on both yield of bio-oil and bio-char resulting from pyrolysis of SWW. The liquid products obtained at various pyrolysis temperatures were subjected into column chromatography after removal of asphaltenes (hexane insoluble). Obtained bio-oils (maltenes or hexane soluble) were classified as aliphatic, aromatic and polar sub-fractions. The maximum of bio-oil yield of 39.5 wt% was obtained at a pyrolysis temperature of 500 °C, particle size between 0.5 and 1 mm, nitrogen flow rate (N2) of 100 mL min−1 and heating rate of 5 °C/min. Liquid product (bio-oil) obtained under the most suitable and optimal condition was characterized by elemental analysis, Nuclear magnetic resonance spectroscopy (1H NMR and 13C NMR), Fourier transformed infrared spectroscopy (FT-IR). The analysis of liquid showed that bio-oil from SWW could be a potential source of renewable fuel production and value added chemical. The yield of char generally decreases with increasing the temperature, the char yield passes from 54.61 to 29.47 wt% at the heating rate of 5 °C/min and from 50.01 to 24.5 wt% at the heating rate of 20 °C/min at the same range of temperature (300–700 °C). Solid products (bio-char) obtained in the presence of nitrogen (N2) contain a very important percentage of carbon and high heating values (HHVs).

Biofuels and biochars production from agricultural biomass wastes by thermochemical conversion technologies: Thermogravimetric analysis and pyrolysis studies

“…Figures 12 and 13a show the FT-IR and H'NMR analysis of bio-oils obtained from pyrolysis of agricultural biomass samples. As can be seen, the results obtained from pyrolysis of all agricultural biomass samples have a representative FT-IR compared with other and previous works and papers (Duan et al, 2020;Guida and Hannioui, 2016;Guida et al, 2020;Ioannidou et al, 2009). The FT-IR absorbance spectrum of sunflower shell, eucalyptus, wheat straw and peanut shell's bio-oils show the presence of several and large amounts of products and functional groups in bio-oil samples.…”

“…These types of biomass with low nitrogen and sulfur contents can be a good nominee for thermochemical conversion process. Low sulfur and nitrogen contents in biomass imply that they release few amounts of NO x and SO x compounds during pyrolysis (Guida et al, 2020;Situmorang et al, 2021;Xin et al, 2020).…”

“…At temperature between 350 and 500 8C, cellulose breaks down and lignin starts to degrade resulting in water, heavier tars and charcoal. At higher temperatures, reaction of gasification takes place forming hydrogen enriched gaseous products (Guida et al, 2018(Guida et al, , 2020Ozbay et al, 2001).…”

“…The absorption peaks between 850 and 1,310 cm À1 indicate the presence of alcohols and phenols compounds and they were shown as the O-H bending and C-O stretching. The presence of aromatics and alkenes functional groups was indicated by the absorbance peaks between 1,610 and 1,640 cm À1 (Guida et al, 2020;Phuakpunk et al, 2020). C5O stretching absorbance between 1,640 and 1,740 cm À1 indicates the presence of aldehydes, carboxylic acids and ketones compounds.…”

“…(Erdil and Erbijik, 2015;Khan et al, 2020;Searcy and Flynn, 2010). Because of its high energy content, high abundance in agricultural growing countries, and high cellulose, hemicellulose and lignin content, agricultural biomass wastes have attracted a lot of scientists, which the aim to produce biofuels (bio-oil, bio-char and gas products) from several and different types of agricultural biomass waste (Guida et al, 2020;Meshitsuka and Isogai, 1996;Worasuwannarak et al, 2007). Thermochemical conversion technology presents a good and viable option for the valorization of several type of lignocellulosic biomass (constituted from cellulose, hemicellulose and lignin).…”