To develop a facile and low-cost nanofibrils process with excellent feedstock adaptability, high-yield lignocellulose nanofibrils (LCNF) are produced directly from wood and non-wood biomass using ...glycerol solvent via screw extrusion pretreatment. Different LCNFs are obtained from four classical raw materials (polar, pine, bamboo, and wheat straw) in this research, followed by comparing their morphological, thermochemical, and mechanical properties. More than 70 wt% of LCNF could be obtained from low-cost substrates except for LCNF from wheat straw with 62.3 wt% yield. Besides, the morphology property of wood LCNF exhibit more uniform distribution over that of non-wood LCNF due to narrower size distribution. Strikingly, despite of the slightly lower LCNF crystallinity various from 52.4% to 62.6% obtained from four substrates, all the LCNFs separated from wood and non-wood biomass exhibit high thermal stability (Tmax over 330 °C), which is higher than conventional nanocellulose, indicating that the crystal area could be well maintained during the pretreated process. Moreover, all the LCNF films show excellent tensile strength which is close to nanocellulose materials. Besides, the Young's modulus of wood-based LCNF films is higher than that of non-wood based LCNF films. Overall, LCNF with excellent performance could be achieved from low-cost biomass by our facile process, which provides a feasible route for industrial production of bio-based nanofilms.
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Activated carbon has been an ideal material for the separation of a variety of chemical pollutants. Its extensive use is limited due to the cost of production, which has triggered the researches on ...the viable option for the non-conventional and cost-effective production. The application of biomass waste has been widely explored as an alternative to expensive methods of activated carbon production from coal. In this study, detailed list of production methods of activated carbon from wood biomass is presented systematically. The attempt has also been made to review the physical properties, such as ultimate and proximate analyses of wood biomass material. Further, the chemical compositions of wood, such as hemicelluloses, cellulose, and lignin are also dealt with. Finally, this review incorporates the existing research papers on wood-derived activated carbons to understand the influence of pyrolysis temperature, activation temperature, and effect of various physical and chemical activation conditions on the production, surface characteristics and adsorption behavior of activated carbons. The outcome of this study revealed that the activated carbons from wood biomass exhibit promising characteristics in terms of surface area, pore size and pore volume, surface functional groups, and surface entrapment behavior against various water soluble chemical toxicants.
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•Utilization of wood waste faces increasing environmental and economic challenges.•Current activated carbon technology requires renewable source as precursor.•Characterized activated carbons have tremendous demand in medical and wastewater treatment industry.•Application of wood waste derived activated carbon have wide possibility.
Effective biological utilization of wood biomass is necessary worldwide. Since several insect larvae can use wood biomass as a nutrient source, studies on their digestive microbial structures are ...expected to reveal a novel rule underlying wood biomass processing. Here, structural inferences for inhabitant bacteria involved in carbon and nitrogen metabolism for beetle larvae, an insect model, were performed to explore the potential rules. Bacterial analysis of larval feces showed enrichment of the phyla Chroloflexi, Gemmatimonadetes, and Planctomycetes, and the genera Bradyrhizobium, Chonella, Corallococcus, Gemmata, Hyphomicrobium, Lutibacterium, Paenibacillus, and Rhodoplanes, as bacteria potential involved in plant growth promotion, nitrogen cycle modulation, and/or environmental protection. The fecal abundances of these bacteria were not necessarily positively correlated with their abundances in the habitat, indicating that they were selectively enriched in the feces of the larvae. Correlation and association analyses predicted that common fecal bacteria might affect carbon and nitrogen metabolism. Based on these hypotheses, structural equation modeling (SEM) statistically estimated that inhabitant bacterial groups involved in carbon and nitrogen metabolism were composed of the phylum Gemmatimonadetes and Planctomycetes, and the genera Bradyrhizobium, Corallococcus, Gemmata, and Paenibacillus, which were among the fecal-enriched bacteria. Nevertheless, the selected common bacteria, i.e., the phyla Acidobacteria, Armatimonadetes, and Bacteroidetes and the genera Candidatus Solibacter, Devosia, Fimbriimonas, Gemmatimonas Opitutus, Sphingobium, and Methanobacterium, were necessary to obtain good fit indices in the SEM. In addition, the composition of the bacterial groups differed depending upon metabolic targets, carbon and nitrogen, and their stable isotopes, δ13C and δ15N, respectively. Thus, the statistically derived causal structural models highlighted that the larval fecal-enriched bacteria and common symbiotic bacteria might selectively play a role in wood biomass carbon and nitrogen metabolism. This information could confer a new perspective that helps us use wood biomass more efficiently and might stimulate innovation in environmental industries in the future.
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•Insect larvae, as a potential incubator for functional bacteria involved in broad environmental control.•Potential bacterial groups involved in carbon and nitrogen metabolism there were classified by SEM.•The SEM-classified groups provided a novel viewpoint underlying wood biomass processing.
•A co-combustion system was designed for green hydrogen production.•Combination of inert porous media and wood pellets achieved a hydrogen growth rate of 142%.•Addition of inert bed significantly ...improved combustion temperature and syngas production.•Hybrid bed with small pellets diameter obtained higher green hydrogen production.
The production of green hydrogen by utilizing wood pellets is an effective way to solve the problem of energy shortage and environmental pollution. In order to improve the hydrogen production efficiency of biomass, a co-combustion system of inert porous media and wood pellets was built, and the combustion characteristic of wood pellets was studied with different porous media structures. The results demonstrated that the increasing of air velocity was beneficial to increase the combustion temperature, and hydrogen production reached the maximum value at v = 4 cm/s. Meanwhile, the hydrogen production increased with the increasing of inert bed length due to the intensification of heat circulation. When the length ratio of the hybrid to inert bed was 6: 3, the lower heating value of syngas was 3.69 MJ/Nm3 and the molar fraction of hydrogen increased by 69 % compared to the single wood pellets combustion. Moreover, the decreasing of pellets diameter was conducive to increase syngas production. The co-combustion of inert porous media and wood pellets realized the efficient utilization of biomass, and maximum growth rate of hydrogen reached 142 %.
With the speedy advancement of wireless communications, electromagnetic wave (EMW) pollution and electromagnetic interference (EMI) are gradually austere, which makes it an urgent need to develop ...high-performance EMW absorbers and shields. Carbon-based materials are important members of the family of EMW absorbing and shielding materials, due to their satisfactory electrical conductivity, low density, and good corrosion resistance. Especially, wood biomass-derived carbon materials, including carbonized cellulose, lignin and wood monolith, are acclaimed for their rich conductive network, unique porous structure, and effective loading of functional fillers, which promotes high-efficiency EMW absorption and shielding, and provides a new idea for using wood biomass resources in a high-value way. Additionally, due to the high yield of wood biomass, the mass production of carbonized wood biomass-derived EMW absorbers and EMI shields becomes more promising compared with other carbon materials. Hence, relevant studies should be summarized. Meanwhile, the functions of carbon materials need to be clarified and the importance of carbon materials needs to be highlighted. In this review, the roles of wood biomass-derived carbon in various EMW absorbing and shielding materials were emphasized, along with an analysis of related studies. Meanwhile, the main obstacles and the prospects of wood biomass-derived carbon were proposed.
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•Clarifying the electromagnetic wave (EMW) absorption/shielding mechanism.•Reviewing the main functions of wood biomass-derived carbon in EMW absorbing/shielding.•Discussing future research directions and challenges of wood biomass-derived carbon.
The evaluation of thermochemical characteristics and the development of kinetic model for pyrolysis of waste biomass are more challenging. In this study, the mass losses, intermediates evolved and ...products formed during pyrolysis of waste wood biomass were determined by coupling DSC/TGA-DTG/GC-MS/FTIR to improve the understanding of conversion processes and decomposition characteristics. The improved non-isothermal kinetics method was proposed by introducing the function of mechanisms, the activation energies and pre-exponential factors were estimated iteratively by regression to enhance modeling accuracy. The results indicated the gases of CO, CO2, CH4, H2 and the liquids of N-containing organics, esters, ketons and carboxylic acids were the most dominated products evolved. The pyrolysis of waste wood biomass could be divided into three phases, and with the increase of heating rates, the caloric requirement for pyrolysis was greatly increased. The random nucleation and one-dimensional diffusion predicted accurately the main (second) and third phases in the pyrolysis of waste wood biomass and waste camphor presented lower activation energies than waste bamboo.
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•Pyrolysis of waste wood is studied by DSC/TG-DTG/GC-MS/FTIR.•Mass loss and energy requirement of pyrolysis are determined by DSC/TGA-DTG.•Gases and liquids of pyrolysis are analyzed by FTIR, GC-MS.•Improved kinetics method is derived to enhance the accuracy of model.
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•Co, Ni, Cu and Zn are successfully used in the preparation of activated carbons by microwave radiation.•The metal atoms have an impact on physicochemical and adsorptive ...properties.•SBET and pore volumes increase with atomic number and decrease with melting point.•Cu-MC, Co-MC and Ni-MC exhibit high hydrophobic properties compared to Zn-MC.•O-nitro phenol is the most adsorbed molecule from aqueous solution.
First-row transition metals (Co, Ni, Cu and Zn) were successfully used in the preparation of activated carbons from wood biomass via microwave-assisted irradiation. Physical-chemical properties of the produced materials (MWAC) were studied by nitrogen adsorption–desorption curves, SEM, FTIR, UV–vis DRS and synchronous fluorescence spectroscopy, CHN elemental analysis, TGA/DTG, pHzpc, hydrophobic properties, and total acidity and basicity groups. Results showed that the metals were bound successfully in different amounts with surface functional groups of the wood biomass through ion exchange and surface complexation interaction during the impregnation step. Zn2+ and Cu2+ formed the most complexes. MWAC impregnated with Zn2+ showed higher pore volumes and surface areas, followed by Cu2+, Co2+ and Ni2+, independently of the ratio used. As the metal : biomass ratio was increased from 0.5 to 2, the surface area of MWAC increased from 300 to 620m2g−1 for Co-MC, 260 to 381m2g−1 for Ni-MC, 449 to 765m2g−1 for Cu-MC and from 572 to 1780m2g−1 for Zn-MC. The samples showed high values of carbon contents and oxygen-containing groups. An adsorption experiment revealed that samples prepared using ZnCl2 showed the highest sorption capacities (qe) for the tested adsorbates, followed by CuCl2, CoCl2 and NiCl2. These results matched with the surface areas and pore volumes trends, which were found to follow atomic number and melting point trends–Ni(II)<Co(II)<Cu(II)<Zn(II), rather than the Irving-Williams Series. The sorption capacities (qe) of molecules followed this order: 2-nitro phenol>bisphenol A>hydroquinone>4-nitro phenol>2-naphtol>paracetamol>caffeine>resorcinol.
This study aims to simulate the steam-enhanced co-gasification of hybrid blends (HB) composed of municipal solid waste (MSW) and urban forest waste (UFW), with torrefaction as pretreatment. ...Experimental (torrefaction), numerical (gasification thermodynamic equilibrium model), and optimization (response surface methodology) techniques evaluated the gasification process to produce (i) hydrogen-rich gas or (ii) enhanced calorific value gas. The torrefaction (225–275 °C), steam-to-biomass (0.4–1.2 S/B) ratio, and HB proportion (0–50% of MSW) influences were investigated to assess H2%, exergy efficiency of H2-production (ηH2), lower heating value (LHV), cold gas efficiency (CGE), and CO2%. The hybrid methodology defined the optimal conditions for 600 °C gasification as (i) 0.9 S/B and an HB comprising 31% MSW and 69% torrefied UFW at 275 °C, presenting an ηH2 of 49%; and (ii) 0.4 S/B and an HB containing 23% MSW and 77% torrefied UFW at 275 °C, showing an LHV of 6126 kJ.Nm−3.
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•Urban solid waste valorization by torrefaction and gasification for H2 production.•Co-gasification of torrefied wood and municipal waste blends for waste mitigation.•Steam-gasification improved the exergy efficiency of H2 production from residues.•Severe torrefaction enhanced the producer gas' quality and reduced carbon emission.•Excellent correlation (R2 = 0.99) of response surface methodology prediction models.
This study investigates the effect of wood biomass energy consumption on CO2 emissions in 27 European Union (EU) member countries for the 1990–2017 period. Applying panel dynamic ordinary least ...squares (DOLS), the results revealed that CO2 emissions decline with an increase in wood biomass energy consumption. While fossil fuel, GDP per capita and trade openness are found to be increasing CO2 emissions. The finding implies that CO2 emissions in EU member countries can be effectively reduced by increasing the amount wood biomass energy consumption in production processes. This will eventually contribute to tackling global warming. The estimated results are considered robust as they were validated by panel FMOLS and pooled OLS. The study recommends for EU member countries to increase the share of wood biomass energy in their energy mix to reduce CO2 emissions. Policy makers in these countries should also invest more in wood biomass energy production to increase its supply and accessibility. The authorities of these countries can equally emphasize on efficiency and sustainability of wood biomass energy to achieve energy security and reduce dependency on fossil fuel.
•This study investigates the impact wood biomass energy consumption on CO2 emissions in EU 27.•Dynamic Ordinary Least Squares (DOLS) was employed to achieve the objective of the study.•The results reveal that wood biomass energy consumption significantly reduces CO2 emissions.•The reduction in CO2 emissions by wood biomass energy is more in top six CO2 emitters than in other EU member countries.
•Thermal degradation of both hardwood and softwood was studied by TG.•A model-fitting method was combined with a model-free method.•Reaction mechanism was predicted by the Coats-Redfern method.•Two ...pyrolysis regions were divided by Ea with the same temperature.•Reaction mechanism was verified as diffusion followed by reaction order model.
Comparative pyrolysis behaviors of typical hardwood (Fagus sylvatica) and softwood (Cunninghamia lanceolata) were investigated based on thermogravimetric analysis over a wide heating rate range from 5K/min to 60K/min. The Flynn-Wall-Ozawa model-free method was applied to estimate the various activation energy values at different conversion rates, and the Coats-Redfern model-fitting method was used to predict the possible reaction mechanism. Two pyrolysis regions were established by the trend of activation energy, divided by the threshold of conversion rate (0.4 for hardwood and 0.2 for softwood) but with the same distinguished temperature at about 580K. For the region under the conversion rate threshold, the activation energy of hardwood increased gradually while softwood decreased. Furthermore, the activation energy remained the same for both hardwood and softwood in the region over the conversion rate threshold. However, softwood behaved greater activation energy than hardwood during the whole pyrolysis process. The pyrolysis differences of hardwood and softwood could be attributed to the chemical component, molecular structure, component proportion and various extractives. The same reaction mechanism of hardwood and softwood was verified by applying the Coats-Redfern approach. By checking activation energies obtained according to different models with those obtained through the Flynn-Wall-Ozawa method, the best model was based on diffusion mechanism when the conversion rate was less than its threshold, otherwise based on reaction order (2nd to 3rd).
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