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In order to identify the most environmental-friendly pretreatment for pyrolsis of wood residue to levoglucosan (LG), for the first time a comparative life cycle assessment (LCA) was carried out for hot water treatment (HWT), torrefaction, acid pretreatment (AP) and salt pretreatment (SP) pathways. Since LG production can facilitate both resource recovery (RR) and wood residue handling (WRH), two different functional units (FUs), i.e., 1 kg LG production and 1 kg wood residue handling were considered. AP was found to generate the least global warming potential of 134.60 kg CO

Biosorbent has attracted considerable attention recently for use in environment remediation and pollution control. Here, a simple and efficient method of one-step alkaline ball milling was designed to prepare porous hickory biosorbent without any thermal treatments. The products were characterized for their ability to remove methyl violet (MV) and titan yellow (TY) organic dyes from aqueous solutions. The one-step alkaline ball milled hickory (OABMH) biosorbent exhibited mesoporous microstructure, homogeneous morphology, and a diversity of oxygen-containing functional groups. Furthermore, OABMH could sorb 212.2 mg g

A synergistic pretreatment that realizing effective fractionation and targeted valorization can guarantee the implementability to future biorefinery scenario. In the present study, a stepwise approach using hydrothermal and deep eutectic solvents (DES) pretreatment was developed to preferentially dissociate hemicelluloses and further remove lignin from poplar, while retaining a cellulose-rich substrate that can be easily digested via enzymatic saccharification to obtain glucose. Results showed that the hydrothermal filtrate is mainly composed of xylooligosaccharide (XOS), monosaccharides, byproducts, and xylan-type hemicelluloses, which have homogenous structures and uniform molecular weights distribution as well as excellent antioxidant activity. Subsequent DES pretreatment further removed the lignin barriers, leading to a remarkable increase in the saccharification efficiency from 15.72% to 96.33% under optimum conditions for enzymatic hydrolysis. In short, the integrated pretreatment is effective for dissociating and chemical conversion of poplar wood, which was reasonable to promote the frontier of highly available biorefinery.

Using co-substrate to accumulate polyhydroxyalkanoate (PHA) is an efficient approach to reduce production cost and improve yield of PHA. In the study, PHA was biosynthesized under full aerobic mode by using rubber wood hydrolysate and xylose co-substrate as the carbon source. The effects of co-substrate on PHA production, microbial community and carbon conversion were explored. The results showed that proper addition of xylose was beneficial for the synthesis of PHA and monomer 3-hydroxyvalerate (3HV). Higher conversion yield of substrate-to-PHA (Y

Wood waste-derived biochar with tunable carbon structure and surface functionality has a great potential for various environmental applications and circular economy; however, a holistic understanding on the application-oriented production of high-efficacy biochar is lacking. Thus, the co-impacts of different pyrolysis conditions (temperature and duration) and activation methods (steam, CO2, and acid pretreatment) on the biochar properties were first investigated. A temperature of 650 ℃ was effective in forming carbonized structure in biochar, while 750 ℃ was critical for the porous structure development. A longer pyrolysis duration (>60 min) enhanced the pore volume without compromising the yield. The activated biochar exhibited a larger pore volume (2.1- to 2.9-fold of pristine biochar) for potential high-end emerging applications. The acid pretreatment effectively removed dissolved organic carbon and most metals from the biochar. This study provides an essential guidance on the fit-for-purpose designs of biochar production conditions for sustainable wood waste management.

Direct land application of food waste digestate (FWD) leads to 60–70% of nitrogen loss through NH3 volatilization due to its innate characteristics like high ammonium nitrogen (NH4+-N) (~6000 mg/kg dry matter) and high moisture content (~75%). Hence, bio stabilization of FWD through composting is a promising solution to curb the environmental and occupational hazards. Hence the aim of this study was to assess the feasibility of using sawdust and/or mature compost as a bulking agent to achieve effective composting. The results showed that mixing of FWD with sawdust alone or together with mature compost could produce quality compost with reduced NH4+-N ( 80%) within 2 weeks of co-composting. Composting FWD with both sawdust and mature compost effectively reduced ~ 83% of NH3 volatilization demonstrating that this approach can effectively produce mature nitrogen enriched FWD compost.

The feasibility of producing polyhydroxyalkanoate (PHA) from pretreated waste wood hydrolysate and volatile fatty acids (VFAs) from sewage fermented products as co-substrate feedstock through mixed microbial cultures (MMCs) process was explored. The results showed that the addition of co-substrate shortened the cycle of PHA reaching the maximum and increased the proportion of 3-hydroxyvalerate (3HV) monomer. Compared with N-excess supply, almost 1.6 times increased PHA accumulation was realized under N-limitation, and simultaneously the highest proportion of 3HV monomer with 51% was also obtained. Additionally, PHA production in S1400 reactor reached a maximum value of about 3088 mg COD/L with culture time to 36 h. The microbial community also displayed a high diversity, which was composed of 65 bacterial genera. It is a novel attempt to accumulate PHA from pretreated waste wood hydrolysate and VFAs co-substrate through MMCs, providing an effective green approach to reduce its expensive cost and achieve mass production.

Recently, the worldwide production of dissolving pulp has grown rapidly. Enzymatic technologies play an important role in producing high-quality dissolving pulp, due to their green, mild conditions, high specificity and efficiency. In this review, the relevant publications regarding enzyme applications for dissolving pulp are summarized. Cellulase and xylanase are two major enzymes used for this purpose. Cellulase can improve the quality of dissolving pulp, such as improving the reactivity/accessibility, controlling the intrinsic viscosity and adjusting the molecular weight. Xylanase is mainly used to increase the purity of the dissolving pulp and improve the pulp brightness. Furthermore, in order to increase the enzymatic treatment efficiency, the enzymatic technology can be combined with other techniques, including mechanical refining, fiber fractionations, alkali treatment and use of additives. The advantages, disadvantages and practical implications are analyzed. Also, the potential of other enzymes (such as laccase, mannanase) are discussed.

Chemi-mechanical pulping, a typical high-yield pulping method, combined with autohydrolysis pretreatment prior to pulping is an efficient and value-added utilization method for biomass in pulp and paper industry. This study investigated the surface lignin changes of poplar sapwood chips in autohydrolysis pretreatment and their effect on the subsequent alkali impregnation for chemi-mechanical pulping. The results showed that the surface lignin content went up with the increase of autohydrolysis intensity, and that the existence of the surface lignin had nearly no impact on the subsequent alkali impregnation in making chemi-mechanical pulps (CMPs) compared to the volume porosity, which was validated by using the stepwise regression analysis. It can be further concluded that autohydrolysis can facilitate the subsequent alkali impregnation of the autohydrolyzed sapwood chips in making CMP, which would be of significance for the combination of biomass refinery and pulp and paper industry.

Torrefaction is a promising pretreatment technology for biomass thermochemical conversion. In this study, pinewood (PW) and PW250 (torrefied at 250 °C) were prepared for pyrolysis. Torrefaction was carried out in a fixed bed reactor and the pyrolysis was studied by thermogravimetric analyzer using six different heating rates. The results showed that the content of hemicellulose in biomass decreased while cellulose and lignin increased after torrefaction. Moreover, the C-O peaks of torrefied biomass was strengthened in FTIR spectrum and the crystallinity degree was enhanced according to XRD analysis. The performance of devolatilization and heat transfer were improved for PW250 while the volatiles only decreased by only 4%. Activation energy was calculated by three iso-conversion methods. It was found that the PW followed D3 diffusion model, while the PW250 followed D1 diffusion model and tended to higher order reaction model at high conversions. In addition, the thermodynamic parameters were compared.

The aim of this study was to pyrolyze individual (oil palm shell, empty fruit bunch and sawdust) as well as blend biomass in a thermogravimetric mass spectrometry (TG-MS) from room temperature to 800 °C at constant heating rate of 15 °C/min. The results showed that the onset TG temperature for blend biomass shifted slightly to lower values. Activation energy values were also found to decrease slightly after blending the biomass. Interestingly, the MS spectra of selected gases (H2O CH4, H2O, C2H2, C2H4 or CO, CH2O, CH3OH, HCl, C3H6, CO2, HCOOH, and C6H12) evolved from blend biomass showed decreased in the intensity as compared to their individual biomass. Overall, the blend biomass showed synergy which provides ways to expand the possibility of utilizing multiple feedstocks in one thermo-chemical system.

In the present work, palm wood was pretreated using hydrothermal technique in conjunction with chemical method for removal of lignin. Pretreated palm wood was subjected to hydrolysis using Trichoderma reesei MTCC 4876. Subsequently bioethanol was produced using palm wood hydrolysate by Kluveromyces marxianus MTCC 1389. RSM was used to identify the non-linear relationship and optimize various process parameters such as parameters such as pH, temperature, agitation rate, substrate concentration and inoculum size for bioethanol production. ANN constructed with 5-2-1 topology was also used to optimize process parameters. The experimental bioethanol yield of 22.90 g/l was obtained at ANN optimum conditions of temperature 45 degrees C, agitation rate 156 rpm, pH 5, substrate concentration 8% (v/v) and inoculum size 3.2% (v/v).

Enzymatic hydrolysis is a method to generate biofuel from biomass, and autohydrolysis is a popular method to pretreat biomass prior to enzymatic hydrolysis. The primary aim of the present study was to determine the role of lignin produced in the autohydrolysis process on the enzymatic hydrolysis of biomass. The HSQC and

Flower waste (FW) is disposed off in the rivers or mixed with solid waste for landfilling that pollutes the environment and causes harmful effects on human health and aquatic life. It is rich in nutrient content and easily converted into the compost. Therefore, the objective of the present research was to optimize the combinations of flower waste and cow dung during agitated pile composting using response surface methodology. Thirteen different agitated piles were used for composting using the central composite design. The optimum combination from central composite design was 65 kg floral waste, 25 kg cattle dung and 10 kg sawdust having 7.10 pH, 3.31 mS cm−1 electrical conductivity, 32.98% total organic carbon and 14 Carbon to Nitrogen ratio during the end phase of the composting period. The nutrient concentrations into the final compost were within the acceptable limit and also found to be beneficial for the growth of plants.

Effects of the addition of 2-naphthol and 2-naphthol-7-sulfonate on the dilute acid pretreatment of mixed wood sawdust were investigated, respectively. Compared to 2-naphthol, 2-naphtnol-7-sulfonate was more effective to enhance delignification and facilitate the enzymatic hydrolysis. The 72 h hydrolysis yield was improved by 47.8% for 2-naphthol-7-sulfone, while only 9.1% was observed for 2-naphthol. The surface charges, enzyme adsorption, and cellulose accessibility of dilute acid pretreated substrates with or without naphthol derivatives were examined. The improved enzymatic hydrolysis by adding 2-naphthol-7-sulfonate was ascribed to the higher negative surface charges, the lower enzyme non-productive binding, and the higher cellulose accessibility of pretreated substrates. Additionally, the HSQC NMR and 31P NMR analysis were carried out on both decomposed lignins and residual bulk lignins. It indicated that the addition of the naphthol derivatives during pretreatment could suppress the lignin repolymerization, which further mitigated the inhibition of residual lignins on enzymatic hydrolysis.

The catalytic activity of engineered biochar was scrutinized for generation of glucose and hydroxymethylfurfural (HMF) from starch-rich food waste (bread, rice, and spaghetti). The biochar catalysts were synthesized by chemical activation of pinewood sawdust with phosphoric acid at 400–600 °C. Higher activation temperatures enhanced the development of porosity and acidity (characterized by C O PO3 and C PO3 surface groups), which imparted higher catalytic activity of H3PO4-activated biochar towards starch hydrolysis and fructose dehydration. Positive correlations were observed between HMF selectivity and ratio of mesopore to micropore volume, and between fructose conversion and total acid density. High yields of glucose (86.5 Cmol% at 150 °C, 20 min) and HMF (30.2 Cmol% at 180 °C, 20 min) were produced from rice starch and bread waste, respectively, over H3PO4-activated biochar. These results highlighted the potential of biochar catalyst in biorefinery as an emerging application of engineered biochar.

Alkali and alkaline earth metal (AAEM) species are the main components of the ash of biomass, and which would influence the combustion of biomass and coal during the co-firing process. The aim of this paper is to investigate the effects of potassium (K), sodium (Na), calcium (Ca), and magnesium (Mg) on the combustion characteristics of pine sawdust (PS) and bituminous coal (BC) by a single particle combustion method. The raw, ash-free and impregnated samples were prepared, and their combustion processes were recorded by a high speed camera. Based on the recorded flame images, the effects of K, Na, Ca and Mg on the combustion characteristics (ignition, volatiles combustion, char combustion) of PS and BC were analyzed. The results reveal that the demineralization treatment brings negative effects on the combustion of PS, which reflects in longer ignition delay time, volatiles and char burnout time, and lower combustion temperature, while the effects on the combustion of BC are opposite. The impregnated samples exhibit shorter ignition delay time, volatiles and char burnout time, and higher combustion temperature than the ash-free samples. In the entire combustion process of PS and BC, K exhibits the strongest promotion effect. When the concentration of K increases from 0 to 2 wt%, the ignition delay time of PS and BC decreases about 5.5 ms and 16.4 ms respectively, the volatiles combustion temperature increases about 41 °C and 77 °C respectively, and the char combustion temperature increases about 226 °C and 141 °C respectively.

Fast microwave-assisted co-pyrolysis of pretreated bamboo sawdust and soapstock was conducted. The pretreatment process was carried out under microwave irradiation. The effects of microwave irradiation temperature, irradiation time, and concentration of hydrochloric acid on product distribution from co-pyrolysis and the relative contents of the major components in bio-oil were investigated. A maximum bio-oil yield of 40.00 wt.% was obtained at 200 °C for 60 min with 0.5 M hydrochloric acid. As pretreatment temperature, reaction time and acid concentration increased, respectively, the relative contents of phenols, diesel fraction (C12 + aliphatics), and other oxygenates decreased. The gasoline fraction (including C5-C12 aliphatics and aromatics) ranged from 55.77% to 73.30% under various pretreatment conditions. Therefore, excessive reaction time and concentration of acid are not beneficial to upgrading bio-oil.

Graphical abstract, Highlights • Low-temperature biochars doubled biomethane production rate and enhanced yields. • Seaweed biochars and hydrochars from various feedstocks reduced biomethane yields. • Biochars with high levels of oxygen surface groups favoured biomethane augmentation., The augmentation of biochar produced at 450 and 600–650 °C and hydrochar produced at 250 °C has been investigated using biochemical methane potential experiments of cellulose. The feedstocks used for the char production included the lignocellulosic (oak wood), macroalgae (Fucus serratus) and aquatic plant (water hyacinth). Biomethane production was improved with the addition of lower-temperature biochars from oak wood (285 mL CH4/g VS) and water hyacinth (294 mL CH4/g VS), corresponding to 7 and 11% more than the control. The addition of these two biochars increased the methane production rate of 2.4 and 2.3 times the control, respectively. Higher temperature biochars showed no difference. Conversely, all hydrochars and macroalgae biochars augmentation reduced methane generation by 57–86 %. The chemical and structural composition of each of the chars differed significantly. Surface oxygen functionality appears to be the most important property of the biochars that improved digestion performance.

The design, modeling and simulation of an integrated biorefinery plant assumed to convert different forestry assortments such as sawdust or shavings (sawmill waste) into bioethanol from cellulose and hemicellulose as the main product, and lignin as the most valuable co-product, was carried out. The proposed lignocellulosic ethanol biorefinery plant was simulated with ProSimPlus. The model was based on experimental results and includes an Organosolv pretreatment, enzymatic hydrolysis, fermentation and distillation to obtain bioethanol. The investigated plant size processed 70,088 tons of biomass/year, with a production capacity of 11,650 tons ethanol/year. Ethanol productivity reached 351 L/ton of dry feedstock. Considering water consumption, approximately 4.8 L of water were needed to produce a liter of ethanol. Finally, the energy targeting through conventional pinch analysis lead to 16.4 MW and 16.07 MW of hot and cold utility energy demand for the entire process respectively with the cogeneration of electricity.

Lignocellulose biodegradation is limited because of its recalcitrant structure particularly when polluted by toxic and carcinogenic compounds such as creosote oil (CRO). As far as we know, this might be the first report that explores the biodegradation of creosote treated wood (CTW) to serve biomethane production. Two novel CTW-degrading microbial consortia, designated as CTW-1 and CTW-2, were screened and constructed to enhance methane production from CRO-treated pine sawdust. After 12 days of biological pretreatment by CTW-1 and CTW-2, a significant reduction in lignocellulosic content of CTW was recorded; estimated as 49 and 43%, respectively. More than 64 and 91% of cumulative biogas and methane yields were obtained from biodegraded CTW over control. Ecotoxicity of treated and untreated CTW was compared by Microtox test. The biodegraded CTW hydrolysates showed a toxicity decrease of more than 80%, suggesting the promising role of constructed microbial consortia for biofuel production and bioremediation.

Formulation of substrates based on three hardwood species combined with modulation of nitrogen content by whey addition (0–2%) was investigated in an experiment designed in D-optimal model for their effects on biological preproceesing of lignocellulosic feedstock by shiitake mushroom (Lentinula edodes) cultivation. Nitrogen loading was shown a more significant role than wood species for both mushroom production and lignocellulose degradation. The fastest mycelial colonisation occurred with no nitrogen supplementation, but the highest mushroom yields were achieved when 1% whey was added. Low nitrogen content resulted in increased delignification and minimal glucan consumption. Delignification was correlated with degradation of syringyl lignin unit, as indicated by a significant reduction (41.5%) of the syringyl-to-guaiacyl ratio after cultivation. No significant changes in substrate crystallinity were observed. The formation of furan aldehydes and aliphatic acids was negligible during the pasteurisation and fungal cultivation, while the content of soluble phenolics increased up to seven-fold.

Enzymatic digestibility of an acid-pretreated poplar (AP, 42.9%) was superior to that of a similarly acid-pretreated larch (AL, 12.5%). Effects of lignin-related recalcitrance on enzymatic hydrolysis were comprehensively investigated by disrupting the two predominant lignin fractions present in acid-pretreated material (extractable lignin and bulk lignin). Lignin removal and bovine serum albumin (BSA) addition were performed to estimate the relative contributions of lignin towards physical blocking and enzyme binding on enzymatic hydrolysis. The lignin physical blocking played a more significant role in limiting the enzymatic hydrolysis of AL. BSA addition improved enzymatic hydrolysis of AP more significantly than AL. Moreover, the effects of lignin embedded in the lignocellulosic matrix on enzyme non-productive binding were compared with the isolated lignin. It indicated that the lignin distribution would influence the lignin effects on enzyme non-productive binding during enzymatic hydrolysis. Results will give insights towards improvement of enzymatic hydrolysis on acid-pretreated woody biomass.

The enzymatic digestibility of softwood is hindered for its highly recalcitrant nature to enzymatic attack. In this study, the effects of dilute sulfuric acid pretreatment (DSAP), acidic sodium chlorite pretreatment (SCP), and their combined pretreatments (DSA-SCP and SC-DSAP) on Chinese fir sawdust were investigated, respectively. Results demonstrated that lignin was the most important obstacle, and digestibility increased linearly with lignin removal yield. Furthermore, the results revealed that the order of sequential pretreatment significantly affected the delignification, and hemicellulose should be removed first. Compared to SC-DSAP, DSA-SCP involving the hemicellulose-removal-first strategy exhibited higher delignification efficiency. DSA-SCP caused lignin removal of 92.3% and the enzymatic hydrolysis was high of 97.9%. Finally, a regression model with high reliability was established to quickly evaluate pretreatment process. In summary, this study highlighted the importance of delignification for saccharification of softwood and unveiled the effect of hemicellulose on delignification.

Plasma gasification of raw and torrefied woody, non-woody, and algal biomass using three different gasifying agents (air, steam, and CO2) is conducted through a thermodynamic analysis. The impacts of feedstock and reaction atmosphere on various performance indices such as syngas yield, pollutant emissions, plasma energy to syngas production ratio (PSR), and plasma gasification efficiency (PGE) are studied. Results show that CO2 plasma gasification gives the lowest PSR, thereby leading to the highest PGE among the three reaction atmospheres. Torrefied biomass displays increased syngas yield and PGE, but is more likely to have a negative environmental impact of N/S pollutants in comparison with raw one, especially for rice straw. However, the exception is for torrefied grape marc and macroalgae which produce lower amounts of S-species under steam and CO2 atmospheres. Overall, torrefied pine wood has the best performance for producing high quality syngas containing low impurities among the investigated feedstocks.

International audience; the aim of this work was to demonstrate the feasibility of second-generation bioethanol production using for the first time a sawmill mixed feedstock comprising four softwood species, representative of biomass resource in auvergne-rhone-alpes region (france). the feedstock was subjected to a microwave-assisted water/ethanol organosolv pretreatment. the investigation focused on enzymatic hydrolysis of this pretreated sawmill feedstock (psf) using cellic® ctec2 as the enzyme, followed by fermentation of the resulting sugar solution using saccharomyces cerevisiae strain. the cellulose-rich psf with 71% w/w cellulose content presented high saccharification yields (up to 80%), which made it perfect for subsequent fermentation; this yield was predicted vs. time up to 5.2% w/v psf loading using a mathematical model fitted only on data at 1.5%. finally, high psf loading (7.5%) and scaleup were shown to impair the saccharification yield, but alcoholic fermentation could still be carried out up to 80% of the theoretical glucose-to-ethanol conversion yield.

This work studied the optimal conditions for pyrolysis of Prosopis juliflora wood in fixed-bed tubular reactor. The optimal conditions are measured by performing pyrolysis experiment with respect to wood properties such as particle size, moisture and pyrolysis condition such as, temperatures, heating rates. Higher solid yield (36.8%) was recorded for a slower heating rate of larger particle size at lower temperatures. Further, higher liquid yield (38.3%) was observed while maintaining high heating rate and temperature. It is observed that with increase in particle size, the yield of char and gas decreases and bio-oil increases. The literature reported biomass pyrolysis kinetic model is validated for Prosopis juliflora wood. The kinetic models are able to predict the performance of fixed-bed tubular reactor in terms of pyrolysis product properties. The validated kinetic model may be used for the design of commercial fixed bed pyrolysis reactor to process Prosopis juliflora wood.

Flower waste is the good source of organic matter which is beneficial for the growth of plants. It can be extracted from the abundant flower waste resources. The present study was carried out to examine the role of sawdust and cow dung on the compost maturity from six different combinations of waste mixture. Role of cow dung was significant, however, saw dust played a critical role to arrest the leachate and also to maintain the aerobic condition. Addition of sawdust is crucial as flower waste may get converted into a lump (ball like structure) without adding the bulking agent. At the completion of composting period, the concentration of macro and micronutrients, CO2 evolution and C/N ratio showed the stable matured compost which is useful for the purpose of agriculture.

Over the last century the pulp and paper sector has assessed various technologies to fractionate woody biomass to produce strong, bright fibers. Several of these processes have also been assessed for their potential to pretreat and fractionate biomass to enhance the subsequent enzymatic hydrolysis of the cellulosic component. Although many of these pretreatments are effective on agricultural residues, softwoods have proven more recalcitrant, primarily due to their high lignin content and structure. As delignification is too expensive to be used routinely a more economically attractive approach might be to alter the lignin. Recent work has shown that, using a modified chemithermomechanical pulping (CTMP) "front end", lignin can be modified and relocated. This significantly enhanced hemicellulose recovery and enzyme-mediated cellulose hydrolysis of woody biomass. As well as being effective on wood chips, the modified CTMP pretreatment process also enhanced the bioconversion of densified feedstocks such as pellets.

The aim of this work was to study the degradation of lignin in raw wood via pretreatment with heteropoly acids as substitutes for traditional H2SO4 in γ-valerolactone/water. By optimizing catalyst concentration, reaction time and temperature, the optimal lignin degradation conditions are obtained (130 °C, 3 h and 20 mM silicotungstic acid). SEM and FTIR measurements demonstrated the efficient lignin degradation ability of HPAs in the GVL/H2O solvent, with negligible damage to cellulose within the raw wood. Furthermore, an elaborated enzymatic hydrolysis study of the thus obtained cellulosic feedstock revealed its suitability for enzymatic digestion, with great potential as starting material for the production of fermentable sugar from biomass in future biorefinery applications.

Recycled wood of two grades (A and B) and spruce were converted on bench (100 o.d. g) and pilot (100 o.d. kg) scales to monosugars, lignin and lignosulfonates using SO2-Ethanol-Water (AVAP®) technology. After digestion, C6 and C5 sugars were recovered at 98–100% and 87–99% for Wood A and Spruce, respectively, while the values for Wood B were 92% and 74–87%. Cellulose was hydrolysed to glucose at 90% or higher using enzyme charge of 7.1 FPU/g glucan. Hemicellulosic sugars were autohydrolyzed to 95–100% monosugars. At bench scale, monosaccharide yield was 609, 561 and 688 kg (hydrous) per BDT biomass for Wood A, Wood B and Spruce, respectively. Corresponding water insoluble lignin yield was 157, 148 and 189 kg per BDT biomass. The preliminary techno-economic evaluation revealed that conversion of recycled wood to sugars using AVAP® fractionation platform results in higher profitability in comparison to virgin wood.

Two kinds of biofuels were produced and compared from hydrothermal carbonization (HTC) and coupling washing with torrefaction (CWT) processes of bamboo sawdust in this study. The mass and energy yields, mass energy density, fuel properties, structural characterizations, combustion behavior and ash behavior during combustion process were investigated. Significant increases in the carbon contents resulted in the improvement of mass energy density and fuel properties of biofuels obtained. Both HTC and CWT improved the safety of the biofuels during the process of handling, storing and transportation. The ash-related issues of the biofuels were significantly mitigated and combustion behavior was remarkably improved after HTC and CWT processes of bamboo sawdust. In general, both HTC and CWT processes are suitable to produce biofuels with high fuel quality from bamboo sawdust.

The reactivity enhancement and viscosity control are of practical importance during the manufacture of high-quality cellulose (also known as dissolving pulp). In the study, the concept of using phosphotungstic acid (HPW) for this purpose was demonstrated. The Fock reactivity of resultant pulp increased from 49.1% to 74.1% after the HPW catalytic treatment at a dosage of 86.4 mg HPW/g odp. The improved results can be attributed to the increased fiber accessibility, thanks to the favorable fiber morphologic changes, such as increased pore volume/size, water retention value and specific surface area. HPW can be readily recycled/reused by evaporating method, where maintaining 87.1% catalytic activity after six recycle times. The HPW catalytic treatment concept may provide a green alternative for the manufacture of high-quality dissolving pulp.

The combination of autohydrolysis and ionic liquid microwave treatments of eucalyptus wood have been studied to facilitate sugar production in a subsequent enzymatic hydrolysis step. Three autohydrolysis conditions (150 °C, 175 °C and 200 °C) in combination with two ionic liquid temperatures (80 °C and 120 °C) were compared in terms of chemical composition, enzymatic digestibility and sugar production. Morphology was measured (using SEM) and the biomass surface was visualized with confocal fluorescence microscopy. The synergistic cooperation of both treatments was demonstrated, enhancing cellulose accessibility. At intermediate autohydrolysis conditions (175 °C) and low ionic liquid temperature (80 °C), a glucan digestibility of 84.4% was obtained. Using SEM micrographs, fractal dimension (as a measure of biomass complexity) and lacunarity (as a measure of homogeneity) were calculated before and after pretreatment. High fractals dimensions and low lacunarities correspond to morphologically complex and homogeneous samples, that are better digested by enzyme cocktails.

The present study reports pyrolysis behavior of three waste biomass using thermogravimetric analysis to determine kinetic parameters at five different heating rates. Physiochemical characterization confirmed that these biomass have the potential for fuel and energy production. Pyrolysis experiments were carried out at five different heating rates (5–25 °C min−1). Five model-free methods such as Kissinger-Akahira-Sunose (KAS), Ozawa-Flynn-Wall (OFW), Friedman, Coats-Redfern, and distributed activation energy (DAEM) were used to calculate the kinetic parameters. The activation energy was found to be 171.66 kJ mol−1, 148.44 kJ mol−1, and 171.24 kJ mol−1 from KAS model; 179.29 kJ mol−1, 156.58 kJ mol−1, and 179.47 kJ mol−1 from OFW model; 168.58 kJ mol−1, 181.53 kJ mol−1, and 184.61 kJ mol−1 from Friedman model; and 206.62 kJ mol−1, 171.63 kJ mol−1, and 160.45 kJ mol−1 from DAEM model for PW, SW, AN biomass respectively. The calculated kinetic parameters are in good agreement with other reported biomass.

The effective separations of cellulose and hemicelluloses from cellulosic fibers are the prerequisite for creating high-value to the abundant and green cellulose materials. In this study, the process concept of cellulase pretreatment, followed by a cold caustic extraction (CCE) was investigated for a softwood sulfite pulp. The results showed that the cellulase pretreatment led to favorable fiber morphological changes, including the increases of the specific surface area (SSA), pore volume and diameter, and the water retention value (WVR). These changes can induce more pronounced fiber swelling in the subsequent CCE process so that the hemicelluloses removal is enhanced. After the cellulase pretreatment (cellulase dosage of 1 mg/g) and CCE process, the cellulose purity was as high as 97.49%, while the hemicelluloses removal selectivity reached 76.42%.

© 2017 Elsevier Ltd Optimisation of conditions for gamma-valerolactone (GVL) pretreatment of Australian eucalyptus sawdust for high cellulose biomass and bioethanol production was demonstrated. Pretreatment parameters investigated included GVL concentrations of 35-50% w/w, temperatures of 120-180 °C and reaction durations of 0.5-2.0 h. Optimum conditions were determined using the response surface method (RSM) and central composite face-centred design. Cellulose content increased from 39.9% to a maximum of 89.3% w/w using treatments with 50% GVL at 156 °C for 0.5 h. Temperature had the most significant effect (RSM p < .05) on cellulose content of residual biomass and reducing operational duration of < 0.5 h may be viable according to RSM. PSSF fermentations of optimised pretreated eucalyptus sawdust produced up to 94% theoretical ethanol yield, which corresponded to approximately 181 kg of ethanol per dry ton of eucalyptus sawdust. The compositions of both the residual biomass and pretreatment liquors show that GVL pretreatment is a promising solvent for lignocellulosic biorefining.

This work presents a first approach concerning the use of Tectona Grandis tree sawdust (from East Timor) for high activated carbon production, by physical activation with carbon dioxide at different temperatures. The activated carbons (AC) obtained exhibit a well-developed porous structure with a pore size distribution varying from micro to mesopores. Selected AC was successfully evaluated for pesticide removal, specific to 4-chloro-2-methylphenoxyacetic acid, from the liquid phase. The results presented are very promising, allowing to establish that Tectona Grandis sawdust is as an excellent precursor for the basic AC production and allow to expect good performance of theses adsorbents on the removal of a broad range of pollutants. It should also be noted that, this achievement is very relevant for developing countries, such East Timor, where Tectona Grandis sawdust is available and may constitute a source of income creating a handle to the technical and industrial development of this region.

In the present study, the effect of temperature and residence time during microwave hydrothermal pretreatment (MHT) on hydrochar properties and pyrolysis behaviors was investigated. Experimental results indicated that higher heating value (HHV) and fixed carbon content gradually increased with increased pretreatment severity. Obvious reduction of oxygen content was found under MHT at 230°C-15min and 210°C-35min. Although lower mass yield was observed under severe conditions, corresponding energy yield was relatively higher. Crystallinity indexes of hydrochar demonstrated an upward trend with increased residence time. Unlike hydroxyl group, dissociation of acetyls was more favorable under prolonged residence time rather than increased temperature. Peaks in thermogravimetric and derivative thermogravimetric curves shifted to higher temperature region under severe conditions, indicating better thermal stability. Py-GC/MS analysis suggested that acids content was decreased but sugars increased with increased MHT severity. Moreover, compared to temperature, residence time was mainly responsible for acetic acid formation.

In this study, the microwave was employed during the alkaline treatment process, in order to separate the hemicelluloses and cellulose from a delignified hardwood kraft pulp. In relation to hemicelluloses yield, the integrated microwave and alkaline treatment resulted in 9.25% and 12.05% at 50°C and 80°C, respectively. Correspondingly, the resultant pulp fibers presented the increased cellulose content, which was desirable for manufacturing dissolving pulp. Additionally, the effect from mechanical refining pretreatment followed microwave and alkaline treatment, on the separation of hemicelluloses and cellulose, was also investigated.

The present study compared the development of various physicochemical properties and the composition of microbial communities involved in the composting process in the solid fraction of dairy manure (SFDM) with a sawdust-regulated SFDM (RDM). The changes in several primary physicochemical properties were similar in the two composting processes, and both resulted in mature end-products within 48days. The bacterial communities in both composting processes primarily comprised Proteobacteria and Bacteroidetes. Firmicutes were predominant in the thermophilic phase, whereas Chloroflexi, Planctomycetes, and Nitrospirae were more abundant in the final mature phase. Furthermore, the succession of bacteria in both groups proceeded in a similar pattern, suggesting that the effects of the bulking material on bacterial dynamics were minor. These results demonstrate the feasibility of composting using only the SFDM, reflected by the evolution of physicochemical properties and the microbial communities involved in the composting process.

A flow-through reactor for hemicelluloses extraction with hot pressurized water was scaled with a factor of 73. System performance was evaluated by comparing the temperature profile, extraction yield and kinetics of the two systems, performing experiments at 160 and 170 °C, 11 barg for 90 min, using catalpa wood as raw material. Hemicellulose yields were 33.9% and 38.8% (lab scale 160 °C and 170 °C) and 35.7% and 41.7% (pilot scale 160 °C and 170 °C). The pilot reactor was upgraded by designing a manifold system capable to provide samples with different liquid residence time during the same experiment. Tests at 140, 150, 160 and 170 °C were carried for 90 min. Increasing yields (9.3–40.6%) and decreasing molecular weights (4078–1417 Da) were obtained at increasing the temperature. Biomass/water ratio of 1/27 gave total average concentration of xylose of 0.4 g/L (140 °C) to 1.8 g/L (170 °C)., MINECO and FEDER Funds, Project CTQ2015-64892-R (BioFraHynery)

Due to the depletion of fossil fuels and their environmental issues, it is necessary to find energy resources which are renewable. Biomass becomes promising feedstock for bio-fuel production. The aim of this study is to investigate thermal decomposition behavior and the effect of third component on the binary mixture pyrolysis using thermogravimetric analysis (TGA). Experiments were carried out at heating rates of 10, 20 and 40°C/min from ambient temperature to 600°C. Two divided groups of peaks were observed in DTG curve of tertiary mixture which the first one was corresponded to microalgae and wood and the second one was belonged to polymer. It is stated that microalgae and wood can improve the degradation process while polymer can delay the decomposition process of mixture. Mentioned positive effect of microalgae and wood could be related to main decomposition temperature and component of microalgae and wood. On the other hand, polymer reduces weight loss of binary mixture and has negative effect of it. The kinetics analysis showed that activation energy (E) and pre-exponential factor (A) of tertiary mixture was slightly lower than that of microalgae-polymer mixture which had the lowest E and A.

Whether lignin benzyl hydroxyl shielding could promote its pyrolysis to phenolic compounds was investigated in this paper. Lignin benzyl hydroxyl was first preoxidized by 2,3-dichloro-5,6-dicyano-1,4-benzoquinone and stabilized by propionaldehyde respectively, then pyrolysis was conducted with milled wood lignin as a control. Organic stable radicals in pyrolytic chars were further detected to reveal lignin pyrolysis chemistry. Results showed that benzyl hydroxyl shielding process weakened lignin thermal stability, and decreased liquid yields regardless of the frequency of lignin β-O-4 linkages. In addition, char yield grew after benzyl hydroxyl shielding. Radical concentration was inversely proportional to β-O-4 content which indicated the non-negligible impact of shielded benzyl hydroxyl on lignin pyrolysis. Furthermore, gases from propionaldehyde stabilized lignin quenched its radicals. This work confirmed that lignin β-O-4 linkages and shielded benzyl hydroxyl both played the great role in radical-mediated pyrolysis, but the enhancement of liquid products could not be achieved via benzyl hydroxyl shielding.

This study aims to explore distinct bacterial strains from wood-feeding termites and to construct novel bacterial consortium for improving the methane yield during anaerobic digestion by degrading birchwood sawdust (BSD) and removing creosote (CRO) compounds simultaneously. A novel bacterial consortium CTB-4 which stands for the molecularly identified species Burkholderia sp., Xanthomonas sp., Shewanella sp., and Pseudomonas mosselii was successfully developed. The CTB-4 consortium showed high efficiency in the removal of naphthalene and phenol. It also revealed reduction in lignin, hemicellulose, and cellulose by 19.4, 52.5, and 76.8%, respectively. The main metabolites after the CRO degradation were acetic acid, succinate, pyruvate, and acetaldehyde. Pretreatment of treated BSD mixed with CRO enhanced the total methane yield (162 L/kg VS) by 82.7% and biomass reduction by 54.7% compared to the untreated substrate. CRO showed a toxicity decrease of >90%, suggesting the efficiency of constructed bacterial consortia in bioremediation and biofuel production.

The pyrolysis behaviors of nine biomass-derived holocelluloses (from seven agricultural and two forestry residues) were studied on a thermogravimetric analyzer (TGA) and pyrolysis–gas chromatography/mass spectrometer (Py-GC/MS). The results illustrated that compared with forestry holocellulose, agricultural holocellulose had quite high ash and hemicellulose contents. Moreover, agricultural holocellulose presented lower initial temperature and maximum mass loss rate. The results of GC/MS revealed that agricultural holocellulose produced more acids, ketones, aldehydes and furans and corn stalk holocellulose led to the highest targeted compounds (ketones, aldehydes and furans with carbonyl group) content of 51.4%. Woody holocellulose was suitable for the production of sugars, particularly levoglucosan, and pine sawdust holocellulose afforded the highest levoglucosan content of 46.55%. Intriguingly, the correlation of sugars/levoglucosan content with a mass ratio of cellulose to hemicellulose (CE/HCE) was put forward.

In this study, the thermal stability of a wood shaving biochar (WS, 650 °C), a chicken litter biochar (CL, 550 °C) and an activated carbon (AC, 1100 °C) were evaluated by combustion at 375 °C for 24 h to remove the labile non-carbonized organic matter. Results showed that WS and CL biochars were not thermally stable and can lose most of the organic C during combustion. The combusted WS and CL biochars retained considerable amounts of negative charge and displayed higher sorption for Cd (from 5.46 to 68.9 mg/g for WS and from 48.5 to 60.9 mg/g for CL). The AC retained 76.5% of its original C and became more negatively chargely after combustion, but its sorption for Cd slightly decreased (from 18.5 to 14.9 mg/g). This study indicated that after potential burning in wildfires (200–500 °C), biochars could have higher sorption capacity for metals by remaining minerals.

Thermal decomposition behavior and kinetics of microalgae Chlorella vulgaris, wood and polypropylene were investigated using thermogravimetric analysis (TGA). Experiments were carried out at heating rates of 10, 20 and 40°C/min from ambient temperature to 600°C. The results show that pyrolysis process of C. vulgaris and wood can be divided into three stages while pyrolysis of polypropylene occurs almost totally in one step. It is shown that wood can delay the pyrolysis of microalgae while microalgae can accelerate the pyrolysis of wood. The existence of polymer during the pyrolysis of microalgae or wood will lead to two divided groups of peaks in DTG curve of mixtures. The results showed that interaction is inhibitive rather than synergistic during the decomposition process of materials. Kinetics of process is studied by the Kissinger-Akahira-Sunose (KAS) and Flynn-Wall-Ozawa (FWO). The average E values obtained from FWO and KAS methods were 131.228 and 142.678kJ/mol, respectively.

The aim of this work was to compare the two most common hydrothermal pre-treatments for wood - mild steam explosion and hot water extraction - both with the prospect of enabling extraction of hemicelluloses and facilitating further processing. Although both involve autohydrolysis of the lignocellulosic tissue, they are performed under different conditions: the most prominent difference is the rapid, disintegrating, discharge employed in the steam explosion opening up the structure. In this comparative study, the emphasis was placed on local composition of the pre-treated wood chips (of industrially relevant size). The results show that short hot water extraction treatments lead to significant variations in the local composition within the wood chips, while steam explosion accomplishes a comparably more even removal of hemicelluloses due to the advective mass transport during the explosion step.

Yellow poplar sawdust (YPS), a wood waste that can be easily collected from a local furniture factory, was fractionated using continuous twin screw-driven reactor for high hemicellulosic sugar recovery. The highest total sugar yields were attained under the following conditions: a barrel temperature of 127°C, sulfuric acid concentration of 0.8wt%, liquid feeding rate of 25mL/min, solid feeding rate of 2.0g/min, screw rotation speed of 25rpm, and residence time of 14.5min. The glucan and hemicellulose contents of the CTSR-fractionated YPS were 47.8% and 10.4%, respectively, and these results indicated that 44.9% of cellulose and 76.3% of the hemicellulose were extracted into liquid hydrolyzate. Meanwhile, the batch fractionation of YPS at the same reaction conditions showed a little fractionation effect, i.e., only 20.5% of hemicellulosic sugar yield was obtained.