Table 1 - uploaded by María González Martínez
Content may be subject to copyright.
Source publication
Fractionated pyrolysis coupled to gas chromatography and mass spectrometry (Py-GC/MS) appears as an interesting analytical tool for elucidating lignocellulosic biomass structure, as it allows the progressive release of chemical fragments representative of biomass macromolecular composition. In this paper the effect of fractionated pyrolysis time (f...
Contexts in source publication
Context 1
... composition in main organic constituents as well as in ash is given in Table 1. The extractive content was measured using an ASE (Accelerated Solvent Extractor) extraction with two cycles at 1500 psi, firstly with water at 110 °C then with acetone at 95 °C. ...
Context 2
... carbohydrate derivatives were levoglucosan and 1,5-anhydro-4-deoxypent-1-en-3-ulose from cellulose and xylan, respectively. A high yield of acetic acid was detected as well, in agreement with the high number of acetyl groups measured (Table 1). Acetic acid can originate from xylan, cellulose and lignin, however elimination of acetyl groups linked to xylan in hemicelluloses are expected to be its major source in beech wood pyrolysis. ...
Context 3
... low temperature region, the formation of acetic acid was closely followed by the formation of 1,5-anhydro-4-deoxypent-1-en-3-ulose, both with a maximum at 350 °C, presumably indicating a common origin from the acetylated xylan units known to be present in beech wood [38]. These observations are in perfect agreement with the hemicellulose composition (essentially xylans) and the acetyl group concentration measured for the sample used in this work (Table 1). However, other mechanisms for the acetic acid formation have also been proposed, as the decomposition of glucuronic acid units in hemicelluloses and through the complex reaction of ring-opened glucose units [45,46]. ...
Context 4
... thermal stability of arabinose was shown to be lower, which is in accord with the release of 1,5-anhydroarabinofuranose at lower temperatures in comparison with the formation of other hemicellulose-derived anhydrosugars. This observation is also supported by the very low concentration of arabinose units (only 2 % of neutral monosugars) in beech hemicelluloses (Table 1). The formation of 1,4-anhydrogalactopyranose was closely followed by the formation of 1,5-anhydro-4-deoxypent-1-en-3-ulose. ...
Context 5
... and 5-hydroxymethylfurfural had also a minor maximum at 350 °C, a temperature for which the formation of levoglucosan had not started yet (profile 4). This supports the theory defending that some compounds are also originated from hexose sugars contained in hemicelluloses, such as galactoglucomannan or glucomannan, as previously reported [51], despite the low concentration of these monosugars in beech hemicelluloses (Table 1). ...
Similar publications
Cornus officinalis Sieb. et Zucc is a traditional Chinese valuable medicinal material. Clinically, it is customary to use ripe fruits from which seeds have been removed for medicinal purposes. The pulp contains 16 amino acids and a large number of essential elements for the human body. In recent years, with the expansion of the application of cornu...
Peanut husks are agro-industrial waste and represent about 20 wt% of the peanut harvest. This waste product was subjected to fast pyrolysis in a pyroprobe reactor coupled with GC/MS at temperatures ranging from 350 to 600 °C to maximize levoglucosan production. Prior to pyrolysis, the biomass was washed with acetic acid (10 wt%) to remove the alkal...
In this study, three type of pretreatment methods (single pretreatment of leaching, single pretreatment of torrefaction, combined pretreatment of leaching and torrefaction) were employed to improve the quality of rice straw. Three leaching agents, namely acid solution, phenol solution, and simulated light bio-oil (SBO), were used. Then, in order to...
This work is part of a larger study, which aims to use soda lignin from straw as the starting point for a non-aqueous consolidant for highly degraded archaeological wood from the Oseberg collection. This wood was treated with alum salts in the early 1900s, is actively degrading and exists in varying states of preservation. Non-aqueous consolidants...
The infrastructure features of the spent mushroom substrate (SMS) were detected and explored based on experimental data acquired from Fourier Transform Infrared Spectroscopy (FTIR), Pyrolysis-Gas Chromatography/Mass Spectrometry (Py-GC/MS) as well as Thermogravimetric Analysis (TG). Further, molecular simulation methods were combined with diverse t...
Citations
... The lignin content was determined by the sum of soluble and insoluble (Klason) lignin as described in TAPPI standard T222 om-83. The elemental sugars content was measured for the biomass and cellulose pulp samples using ion chromatography after a two-stage sulphuric acid hydrolysis of samples, as described in TAPPI standard T249 cm-80 as detailed in another study 52 . The neutral monosugars obtained were quantified by ion chromatography using a Dionex ICS5000 system. ...
Unprecedented efforts are being deployed to develop hydrogen production from bioresources in a circular economy approach, yet their implementation remains scarce. Today’s Challenges are associated with the shortage in the value chain, lack of large-scale production infrastructure, high costs, and low efficiency of current solutions. Herein, we report a hydrogen production route from cellulose pulp, integrating biomass fractionation and gasification in a biorefinery approach. Softwood sawdust undergoes formic acid organosolv treatment to extract cellulose, followed by steam gasification. High-purity hydrogen-rich syngas at a concentration of 56.3 vol% and a yield of 40 gH2/kgcellulose was produced. Char gasification offers the advantage of producing free-tar syngas reducing cleaning costs and mitigating downstream issues. A comprehensive assessment of mass and energy balance along the hydrogen value chain revealed an efficiency of 26.5% for hydrogen production, with an energy requirement of 111.1 kWh/kgH2. Optimizing solvent recovery and valorization of other constituents as added-value products in a biorefinery approach would further improve the process and entice its industrial takeoff.
... At a pyrolysis temperature of 350 • C, phenolic compounds such as eugenol (G6), aldehydes, ketones, or alcohol group from G-and S-unit were released. Other compounds such as vanillin (G7) and acetoguaiacone from G-unit were degraded at 200-400 • C, in which the β-ether was separated [67]. ...
The efficient isolation process and understanding of lignin properties are essential to determine key features and insights for more effective lignin valorization as a renewable feedstock for the production of bio-based chemicals including wood adhesives. This study successfully used dilute acid precipitation to recover lignin from black liquor (BL) through a single-step and ethanol-fractionated-step, with a lignin recovery of ~35% and ~16%, respectively. The physical characteristics
of lignin, i.e., its morphological structure, were evaluated by scanning electron microscopy (SEM). The chemical properties of the isolated lignin were characterized using comprehensive analytical techniques such as chemical composition, solubility test, morphological structure, Fourier-transform infrared spectroscopy (FTIR), 1H and 13C Nuclear Magnetic Resonance (NMR), elucidation structure by pyrolysis-gas chromatography-mass spectroscopy (Py-GCMS), and gel permeation chromatography (GPC). The fingerprint analysis by FTIR detected the unique peaks corresponding to lignin, such as C=C and C-O in aromatic rings, but no significant differences in the fingerprint result between both lignin. The 1H and 13C NMR showed unique signals related to functional groups in lignin molecules such as methoxy, aromatic protons, aldehyde, and carboxylic acid. The lower insoluble acid content of lignin derived from fractionated-step (69.94%) than single-step (77.45%) correlated to lignin yield, total phenolic content, solubility, thermal stability, and molecular distribution. It contradicted the syringyl/guaiacyl (S/G) units’ ratio where ethanol fractionation slightly increased syringyl unit content, increasing the S/G ratio. Hence, the fractionation step affected more rupture and pores on the
lignin morphological surface than the ethanol-fractionated step. The interrelationships between these chemical and physicochemical as well as different isolation methods were investigated. The results obtained could enhance the wider industrial application of lignin in manufacturing wood-based composites with improved properties and lower environmental impact.
... The elemental sugars content was measured for the extracted celluloses and Avicel cellulose samples through ion chromatography after a two-step hydrolysis of samples in sulfuric acid (TAPPI standard T249 cm-85), as described in (González Martínez et al. 2019). ...
Biomass composition on cellulose, hemicelluloses and lignin determinates its behavior in torrefaction (200–350 °C, default-oxygen atmosphere). Up to now, commercial microcrystalline cellulose was typically used to represent cellulose behavior in biomass torrefaction models based on macromolecular components. The objective of this work is to evaluate the impact of cellulose properties on its behavior in torrefaction, so as to identify the most suitable cellulose sample for modelling. To do this, five extracted celluloses from woody and agricultural biomass, commercial microcrystalline cellulose (Avicel) and four cotton linters tailored to different degrees of polymerization (DP) were considered. Cellulosic samples were deeply characterized in terms of fiber analysis, molar mass distribution (MMD), hydrodynamic behavior (SEC-RALS) and allomorphic structure. Cellulosic samples were torrefied in a thermogravimetric analysis up to two temperatures, leading to partial (300 °C) and total (350 °C) cellulose degradation. Extracted celluloses and Avicel cellulose degradation profiles showed strong differences at 300 °C. Polymer MMD, dispersity and the presence of residual hemicellulose sugars, especially xylose, strongly impacted cellulose degradation through torrefaction. Extracted celluloses presented high purity, narrow MMD and high DP, but a cellulose II structure due to mercerization. This cellulosic allomorph was shown to be more reactive, but it led to an identical final solid mass loss. The observed hydrodynamic behavior and the probable preservation of cellulose amorphous areas from native cellulose may also influence polymer structural behavior in torrefaction. Finally, at least one-order-of-magnitude DP variation was shown to be required to see an impact in cellulose degradation profile through torrefaction.
... Environmental pollution and energy shortage have become the main contradictions restricting the sustainable development of economy and society. Biomass has attracted people's attention for its renewability, availability, carbon neutrality, less dependency on fossil fuels, and other advantages [1][2][3][4]. Woody biomass derived from trees is a vital biomass resource since new forests can be regenerated through afforestation and appropriate maintenance [5]. The construction scrap wood is almost completely utilized in construction materials. ...
... The IR peak at 3200 cm −1 was ascribed to the stretching vibration-OH in boric acid. The IR absorption peak at 1375 cm −1 was attributed to the unsymmetrical stretching vibration of the B-O bond in B(OH) 3 . The absorption peak at 1340 cm −1 was attributed to the bridge stretching vibration of the B-O-C bond [42], corresponding to the scattering characteristic peak at 1338 cm −1 in the Raman spectrum. ...
Boric acid is recently proved to be a good substitute for conventional acidic catalytic materials. However, few studies used boric acid as a catalyst in biomass pyrolysis. This study focused on the catalytic effects of boric acid (BA) on pyrolysis behaviors of woody biomass. The birch wood flour (WF) was used as feedstock and treated by impregnation of boric acid solution. Both untreated and boric acid-treated samples (BW) were characterized by FTIR and SEM. Thermogravimetry (TG) and pyrolysis coupled with gas chromatography and mass spectrometry (Py-GC/MS) techniques were used for studying mass loss, composition, and distribution of evolved volatiles formed from pyrolysis process. Additionally, a small fixed-bed pyrolyzer with an amplificated loading amount was used to prepare liquid products, and further, GC/MS were used to analyze the composition of these liquid products. Different pyrolysis temperatures and boric acid/wood flour mass ratios were also studied. The main results are as follows. Boric acid infiltrated into both cell cavity and cell wall through impregnation treatment. FTIR analysis showed that boric acid reacted with wood flour to form B-O-C bond during the treatment. After the treatment of boric acid, the initial degradation temperatures and residual carbon contents were increased, while the maximum weight loss rates were decreased. Boric acid significantly altered the composition and distribution of volatile pyrolysis products of wood flour. It significantly increased the contents of small molecule compounds such as acetic acid and furfural but, decreased the contents of phenol derivatives with high molecular weights. And these changes became more pronounced as the temperature increased. When mass ratio of boric acid (BA) to wood flour (WF) was 2, the acetic acid accounted for 91.28% of the total product in the pyrolysis liquid, which was 14 times higher than that of untreated wood flour. Boric acid effectively catalyzed fast pyrolysis of woody biomass to selectively produce acetic acid
... There are few studies focusing on the stepwise pyrolysis of lignin currently. Chen et al. [13] studied twostage thermos-degradation behaviors of lignin by setting the torrefaction at 250-300°C and pyrolysis at 500°C using pyrolysis-gas chromatography/mass spectrometry (Py-GC/ MS), and the results indicated that the torrefaction could stabilize pyrolysis bio-oil, make its composition more uniform, separate certain chemicals, and increase the selectivity of aromatic compounds. However, the effects of wider pyrolysis temperature ranges and residence time are necessary to be investigated further. ...
To explore a new way of utilizing lignin and deepen the understanding of mechanism of two-step pyrolysis (TSP) of biomass, the effects of the first step pyrolysis temperature (T1) and residence time (RT1) on TSP of lignin were studied by using pyrolysis gas chromatography/mass spectrometry (Py-GC/MS). TSP of lignin was also compared with one-step pyrolysis (OSP) of lignin. The results indicated that higher pyrolysis temperature promoted the break of ether linkage among the structural elements of lignin and the removal of side chains. With T1 increasing, the contents of monophenols (MPs), catechols (CPs), monocyclic aromatic hydrocarbons (MAHs), and polycyclic aromatic hydrocarbons (PAHs) increased in the first step, while the contents of methoxyphenols with double bond in the side-chain (MPBSs) and methoxyphenols with no double bond in the side-chain (MPSs) increased firstly and then decreased. In the second step, with T1 increasing the contents of MPs and CPs increased firstly and then decreased, the contents of MAHs and PAHs increased significantly, and the contents of MPBSs and MPSs decreased. Higher T1 increased the yields of the most identified compounds of the first step, but decreased the yields of MPs, CPs, MPBSs, and MPSs in the second step. RT1 had great effects on the pyrolysis behaviors and product distribution of TSP of lignin, and the content of MAHs and PAHs in the second step increased significantly with RT1 increasing. Compared with OSP, the yields of MAHs and PAHs could increase in the second step. TSP of lignin could improve the selectivity of value-added chemicals remarkably, such as guaiacol, vanillin, acetovanillone in the first step, and the selectivity of benzene, toluene, m-xylene, phenol, o-cresol, and p-cresol in the second step.
... According to (González Martínez et al., 2019), the length of the pyrolysis process has a considerable impact on the amount and type of pyrovapours produced. Therefore, sequential pyrolysis was performed to determine the process duration for the analysed fractions, following the methodology reported by (Kleen et al., 2003;Selsbo et al., 1997). ...
Fuelled by further planet degradation concerns, the circular economy concept spreads worldwide, incorporating the need for the closing of material loops. This can be done not only by waste prevention and recycling but also by excavating old landfill sites. In line with this need, the Enhanced Landfill Mining concept was developed, which covers mining of old landfills combined with material and energy recovery from the excavated material. Site-specific investigations of excavated material are required because the way of excavated material utilisation has to be individually tailored to the material features. In this article, the valorisation options for the excavated waste from the old part of the landfill located in Mont-Saint-Guibert (Belgium) are preliminarily assessed. Seven separated waste fractions were analysed regarding their thermal decomposition pattern (TGA), pyrolysis potential (Py-GC/MS), and elemental composition (ICP-OES). Most of the analysed fractions are characterised by a highly heterogeneous composition, which excludes their primary or secondary recycling. The fractions are also characterised by high calorific value, which indicates the potential for thermochemical utilisation (i.e., pyrolysis). The presence of a significant amount of heavy metals (especially Hg and Pb) and chlorine may, however, pose a considerable risk of the contamination of pyrolysis products. It may require costly washing of the feedstock prior to the utilisation or cleaning of the process products prior to their use. Therefore, in order to limit additional costs, collective pyrolysis of all fractions seems to be a feasible way of their utilisation.
... Neutral sugar composition was determined by the ASTM E1758 standard method. Characterization data from neutral sugar composition were normalized to 100% as described in [38]. The macromolecular composition is in agreement with previous studies in the literature [39][40][41][42]. ...
Biomass preheating in torrefaction at an industrial scale is possible through a direct contact with the hot gases released. However, their high water-content implies introducing moisture (around 20% v/v) in the torrefaction atmosphere, which may impact biomass thermochemical transformation. In this work, this situation was investigated for wheat straw, beech wood and pine forest residue in torrefaction in two complementary experimental devices. Firstly, experiments in chemical regime carried out in a thermogravimetric analyzer (TGA) showed that biomass degradation started from lower temperatures and was faster under a moist atmosphere (20% v/v water content) for all biomass samples. This suggests that moisture might promote biomass components’ degradation reactions from lower temperatures than those observed under a dry atmosphere. Furthermore, biomass inorganic composition might play a role in the extent of biomass degradation in torrefaction in the presence of moisture. Secondly, torrefaction experiments on a lab-scale device made possible to assess the influence of temperature and residence time under dry and 100% moist atmosphere. In this case, the difference in solid mass loss between dry and moist torrefaction was only significant for wheat straw. Globally, an effect of water vapor on biomass transformation through torrefaction was observed (maximum 10%db), which appeared to be dependent on the biomass type and composition.
... 34 In addition, the liquid products of oxidative AP torrefaction contained a certain amount of 5-hydroxymethylfurfural, which was directly derived from cellulose. 35 2-Furaldehyde diethyl acetal was the main aldehyde in liquid products derived from AP torrefaction. The alcohols of liquid products derived from GP torrefaction were mainly 3-pyridinol and 3-methyl-1butanol. ...
... The carbohydrate composition was determined after a second acidic post-hydrolysis of the liquor to depolymerize all remaining oligomers to monosaccharides using diluted H2SO4 aqueous solution (2 %) for 1 h at 121°C in an autoclave [63]. Monosugar content was determined from ionic liquid chromatography after acidic hydrolysis of the polysaccharides. ...
... Polysaccharide based-fractions were characterized in terms of sugar composition and acetyl group content (Table 1) as defined in [41,58,63]. Sugar composition of the raw biomasses was also added to Table 1 for comparison [41]. ...
The behavior of biomass in torrefaction is determined by that of its macromolecular components, as well as by the biomass type. However, up to now, commercial compounds were typically used for modelling biomass torrefaction. This work proposes to assess the behavior of cellulose, hemicelluloses and lignin in torrefaction through extracted fractions directly isolated from woody and agricultural biomasses (ash-wood, beech, miscanthus, pine and wheat straw) thanks to an optimized extraction procedure. The solid kinetics of these extracted fractions were analyzed through thermogravimetric analysis (TGA) in chemical regime conditions (200–300 °C at 3 °C·min⁻¹ followed by 30 min at 300 °C). These experiments highlighted the influence of the biomass type and the sugar composition in the degradation of the polysaccharide fractions in torrefaction, particularly for hemicelluloses. Furthermore, the degree of preservation of the native structure of the macromolecular components, when extracting them from biomass, seems also having an impact their behavior, especially for cellulose. The comparison of the torrefaction solid kinetic profiles of these extracted fractions, dependent on the biomass type, to that of commercial compounds from previous studies suggest that these extracted fractions would be more suitable for biomass torrefaction modelling.
... The possible reason for presence of carbohydrate derivatives was that cellulose and hemicellulose were not completely removed during the enzymatic hydrolysis of feedstock, resulting in feedstock containing a small portion of cellulose or hemicellulose (about 5 wt-10 wt%) [28]. Due to the cleavage of bonds between lignin and polysaccharide, a certain amount of carbohydrate derivatives could also be partially formed [29]. Methylene succinic acid ...
This paper investigated the pyrolytic behaviors of enzymatic hydrolysis lignin (EHL) and EHL treated with steam explosion (EHL-SE) by pyrolysis-gas chromatography/mass spectrometer (Py-GC/MS). It was shown that the main component of the pyrolysis products was phenolic compounds, including G-type, H-type, S-type, and C-type phenols. With different treatment methods, the proportion of units in phenolic products had changed significantly. Meanwhile, proximate, elemental, and FTIR analysis of both lignin substrates were also carried out for a further understanding of the lignin structure and composition with or without steam explosion treatment. FTIR result showed that, after steam explosion treatment, the fundamental structural framework of the lignin substrate was almost unchangeable, but the content of lignin constituent units, e.g., hydroxyl group and alkyl group, evidently changed. It was noticeable that 2-methoxy-4-vinylphenol with 11% relative content was the most predominant pyrolytic product for lignin after steam explosion treatment. Combined with the above analysis, the structural change and pyrolysis product distribution of EHL with or without steam explosion treatment could be better understood, providing more support for the multi-functional utilization of lignin.
