Poplar Wood Chips Research Articles

Size Reduction Characteristics of Yellow Poplar in a Laboratory Knife Mill

ABSTRACT Size reduction is one of the major pre-processing operations in using biomass as a source of energy or rawmaterials for forest products industry. The grinding characteristics of dried yellow poplar wood chips wereinvestigated using laboratory knife mill with three different screen aperture diameters to provide the basicinformation for the optimizing of size reduction processes in biomass industry. Average specific energy con-sumptions were 0.157, 0.137, and 0.093 Wh/g for the screen aperture diameters of 5.0, 7.5, and 9.0 mm, respectively. According to the results of size distribution analysis of ground particles, the sizes of the most of ground particles were much smaller than the aperture diameters of the screens installed on knife mill used in this study. Keywords : size reduction, biomass, knife mill, specific energy consumption for milling, particle size distribution, Liriodendron tulipifera L. 1 Date Received November 19, 2015, Date Accepted December 28, 2015 2 College of Agriculture and Life Science, Chonnam National University, Gwangju 61186, Republic of Korea

Valorization of Hemicelluloses: Production of Bioxylitol from Poplar Wood Prehydrolyzates by Candida guilliermondii FTI 20037

In this study on the valorization of hemicelluloses (a co-product generated during cellulosic bioethanol production), prehydrolyzates obtained from poplar woodchips pretreated in an industrial experimental steam-explosion pilot-plant facility were evaluated for the production of bioxylitol using the yeast, Candida guilliermondii FTI 20037, employing both batch and fed-batch fermentation modes in shake flasks on defined nutrient medium. The prehydrolyzates consisted of monosaccharides (pentose and hexose sugars) as well as xylo-oligosaccharides and undegraded hemicellulose. Xylose (31.6 ± 0.57 g/L) was the major sugar in the prehydrolyzates that also contained acetic acid and degradation products of lignin and sugars (phenolic and furanic compounds). Xylose in the prehydrolyzates could be further increased (106.4 ± 0.02 g/L) through an acid hydrolysis step (0.6 % (w/v) H2SO4). Compounds of a toxic nature in both the acid hydrolyzates and prehydrolyzates were removed by treatment with Amberlite IRA-400 resin (chloride form). Batch fermentation of pure xylose and poplar prehydrolyzate resulted in bioxylitol production of 9.9 ± 0.01 and 4.9 ± 0.17 g/L, respectively, indicating that the poplar prehydrolyzates exhibited an inhibitory effect on fermentation. After detoxification of the poplar prehydrolyzates, bioxylitol production increased to 8.9 ± 0.01 g/L. Fed-batch fermentation of the prehydrolyzate increased the bioxylitol production to 12.39 ± 0.33 g/L, while acid hydrolysis followed by detoxification resulted in a maximum bioxylitol production of 22.0 ± 0.01 g/L, a 348 % increase. The results demonstrated that acid hydrolysis and detoxification followed by fed-batch fermentation was an efficient way to produce bioxylitol from poplar prehydrolyzates.

The influence of lignin on steam pretreatment and mechanical pulping of poplar to achieve high sugar recovery and ease of enzymatic hydrolysis

With the goal of enhancing overall carbohydrate recovery and reducing enzyme loading refiner mechanical pulping and steam pretreatment (210°C, 5min) were used to pretreat poplar wood chips. Neutral sulphonation post-treatment indicated that, although the lignin present in the steam pretreated substrate was less reactive, the cellulose-rich, water insoluble component was more accessible to cellulases and Simons stain. This was likely due to lignin relocation as the relative surface lignin measured by X-ray photoelectron spectroscopy increased from 0.4 to 0.8. The integration of sulphite directly into steam pretreatment resulted in the solubilisation of 60% of the lignin while more than 80% of the carbohydrate present in the original substrate was recovered in the water insoluble fraction after Na2CO3 addition. More than 80% of the sugars present in the original cellulose and xylan could be recovered after 48h using an enzyme loading of 20mgprotein/g cellulose at a 10% substrate concentration.

Horizontal gene transfer and gene dosage drives adaptation to wood colonization in a tree pathogen

Some of the most damaging tree pathogens can attack woody stems, causing lesions (cankers) that may be lethal. To identify the genomic determinants of wood colonization leading to canker formation, we sequenced the genomes of the poplar canker pathogen, Mycosphaerella populorum, and the closely related poplar leaf pathogen, M. populicola. A secondary metabolite cluster unique to M. populorum is fully activated following induction by poplar wood and leaves. In addition, genes encoding hemicellulose-degrading enzymes, peptidases, and metabolite transporters were more abundant and were up-regulated in M. populorum growing on poplar wood-chip medium compared with M. populicola. The secondary gene cluster and several of the carbohydrate degradation genes have the signature of horizontal transfer from ascomycete fungi associated with wood decay and from prokaryotes. Acquisition and maintenance of the gene battery necessary for growth in woody tissues and gene dosage resulting in gene expression reconfiguration appear to be responsible for the adaptation of M. populorum to infect, colonize, and cause mortality on poplar woody stems.

Value Adding of Poplar Hemicellulosic Prehydrolyzates: Laccase Production by Botryosphaeria rhodina MAMB-05 and Its Application in the Detoxification of Prehydrolyzates

Fast-growing hybrid poplar species are attractive as feedstocks for the production of bio-based chemicals including biofuels. Pretreatment makes cellulose accessible to enzymatic hydrolysis, producing hemicellulose and lignin as major co-products. Poplar woodchips pretreated hydrothermally in an experimental industrial pilot-plant generated two prehydrolyzate streams; purge-condensate collected from cooking the woodchips and press-filtrate collected after the fiber explosion step. Both prehydrolyzates contain hemicellulose sugars (pentoses, hexoses, oligosaccharides), acetic acid, and degradation products from hemicellulose and lignin (furanic and phenolic compounds, respectively). Purge prehydrolyzate was highly diluted, of low sugar content and high biochemical/chemical oxygen demand, and constituted a process waste that was addressed for value-adding through production of enzymes by fermentation. Wood-decay fungi were screened for laccases on purge prehydrolyzate, with Botryosphaeria rhodina producing highest titers. B. rhodina detoxified the prehydrolyzate but at expense of sugar consumption. Adding xylose and glycerol to purge did not inhibit fungal growth or impede laccase production. Phenolics in the purge had inducing effect on enhancing laccase titers. Laccase production was optimized by Box-Behnken-(33)-factorial design varying the concentration of xylose in the purge, together with adding copper as laccase inducer and glycerol to increase the level of fermentable substrate, resulting in optimal enzyme titers (36.37 ± 3.52U/mL; validated). The crude laccase preparation was employed to detoxify the more concentrated press prehydrolyzate, reducing the overall content of phenolics by ∼30 %. Chromatographic (high-performance liquid chromatography-ultraviolet, gas chromatography/mass spectrometry) analysis identified various phenolic compounds present in the press prehydrolyzate following laccase treatment, and in the presence of the mediator, ABTS, the phenolics content decreased further.

Effect of Hot-Pressing Temperature on the Subsequent Enzymatic Saccharification and Fermentation Performance of SPORL Pretreated Forest Biomass

Methods to increase the energy density of biofuel feedstock for shipment are important towards improving supply chain efficiency in upstream processes. Towards this end, densified pretreated lignocellulosic biomass was produced using hot-pressing. The effects of fiber hornification induced by hot-pressing on enzymatic digestibilities of lodgepole pine and poplar NE222 wood chips pretreated by sulfite pretreatment to overcome recalcitrance of lignocelluloses (SPORL) were examined. Pretreated wood chips were pressed at 25, 70, 90, 110, and 177 °C. The cellulose accessibilities of the pressed and unpressed substrates were evaluated using water retention value and direct cellulase adsorption measurements. Hot-pressing below 110 °C produced a degree of hornification (DH) below 0.26 and had limited effect on cellulose accessibility and enzymatic digestibility. Hot-pressing at 177 °C produced a DH of 0.86 that substantially hornified the fibers and resulted near zero saccharification. The saccharification results were consistent with cellulose accessibility data. Ethanol fermentation studies at 18 % solids suggest that a pressing below 110 °C is preferred to reduce its effect on biofuel yield.

Evaluation of lignocellulolytic activities of ten fungal species able to degrade poplar wood

The study of wood decay fungi that naturally biodegrade lignocellulosic polymers has been steadily increasing during the past two decades due to their industrial and innovative applications. In this work, we compare ten species of lignicolous macrofungi which develop fruiting bodies on poplar in relation to their capacity for growing on poplar wood chips and sawdust and of secreting cell wall degrading enzymes. All the fungi studied appeared to be able to grow well in these conditions and to secrete cellulase and hemicellulase, Mn-peroxidase and cellobiose dehydrogenase, while Li-peroxidase and laccase were produced by seven and six out of the ten species, respectively. Variability in the levels of all these enzymatic activities was assessed. Two species, never investigated before, showed the best performances as regards production of cellulolytic and hemicellulolytic activities (Lenzites warnieri) and Mn-peroxidase (Perenniporia meridionalis). The highest laccase level was detected in the well known plant pathogen Fomes fomentarius, and the brown-rot Daedalea quercina proved to be the best producer of lignin peroxidase and cellobiose dehydrogenase.

Exergetic analysis of a fast pyrolysis process for bio-oil production

This paper presents an exergetic analysis of a fast pyrolysis plant simulated in Aspen Plus, producing crude bio-oil from lignocellulosic feedstock (hybrid poplar woodchips). The simulation includes the drying and pretreatment of the biomass, the pyrolysis reactor, product recovery, and a combustion reactor that provides the process heat. Chemical and physical exergies are determined for all process streams and the exergy destruction is calculated at the component level of the plant. The overall exergetic efficiency of the plant is found to be 71.2%, with the gas-and-char combustor of the plant causing the highest exergy destruction. Relatively high irreversibilities are also calculated in the pyrolysis reactor and the bio-oil recovery section (quench and water cooler), as well as in the dryer and the mill. Further investigation shows considerable potential for improvement when introducing the hot exhaust gases of the combustor directly in the dryer without using part of their thermal energy for preheating the combustion air. This measure increases the overall plant efficiency to 73.2% by reducing the inefficiencies in the dryer and the heat exchangers. Lastly, the contribution of the compressors and pumps to the overall exergy destruction is found to be rather small.

Effect of composting on the Cd, Zn and Mn content and fractionation in feedstock mixtures with wood chips from a short-rotation coppice and bark

Micronutrient content and availability in composts may be affected by the addition of wood chips or tree bark as a bulking agent in the compost feedstock. In the first part of this study, micronutrient levels were assessed in bark and wood of poplar and willow clones in a short-rotation coppice. Large differences between species were observed in bark concentrations for Cd, Zn and Mn. In the second part of the study, we aimed to determine the effect of feedstock composition and composting on Cd, Zn and Mn concentrations and availability. By means of three composting experiments we examined the effect of (a) bark of different tree species, (b) the amount of bark, and (c) the use of bark versus wood chips. In general, compost characteristics such as pH, organic matter and nutrient content varied due to differences in feedstock mixture and composting process. During the composting process, the availability of Cd, Zn and Mn decreased, although the use of willow and poplar bark or wood chips resulted in elevated total Cd, Zn or Mn concentrations in the compost. Cd concentrations in some composts even exceeded legal criteria. Cd and Zn were mainly bound in the reducible fraction extracted with 0.5M NH2OH⋅HCl. A higher acid-extractable fraction for Mn than for Cd and Zn was found. Higher Cd concentrations in the compost due to the use of bark or wood chips did not result in higher risk of Cd leaching. The results of the pH-stat experiment with gradual acidification of composts illustrated that only a strong pH decline in the compost results in higher availability of Cd, Zn and Mn.

Structural Characterization of Pre-hydrolysis Liquor Lignin and Its Comparison with Other Technical Lignins

The kraft-based dissolving pulp production process can be a model for the forest biorefinery concept. The objective of this study is to characterize the dissolved lignin present in the pre-hydrolysis liquor (PHL) to facilitate its subsequent use following the forest biorefinery concept. In this work, lignin was isolated from PHL by acidification using dilute H2SO4, followed by purification through dissolution in a dioxane solution (9:1) and re-precipitation with diethyl ether. The characteristics of PHL lignin were compared with those of the dioxane lignin, acetic acid (AA) lignin and ethanosolv (EL) lignin isolated from the same mixed hardwood (maple, poplar and birch wood chips, in a ratio of 7:2:1), which is the raw material used for dissolving pulp production. The obtained lignin samples were characterized by UV, FTIR, 1H-NMR spectroscopy, molecular weight determination, elemental and methoxyl analyses. The results showed that the absorptivity of dioxane lignin at 276 nm was 10.0 l g-1cm-1, while that of PHL lignin was 17.2 l g-1cm-1. The presence of condensed structures in the PHL lignin was also observed in the FTIR spectrum (strong bands at 870 and 890 cm-1), which was also present in the AA and EL lignins. The lignin isolated from PHL had a lower molecular weight and methoxyl group per C9 unit, in comparison with other lignin samples. 1H-NMR analysis indicated a significant increase in the phenolic hydroxyl content in the PHL lignin, caused by cleavage of aryl-ether bonds during the prehydrolysis. Keywords: PHL lignin, Dissolving pulp, Kraft pulping, Characteristics, Phenolic hydroxyl group, Molecular weight, Methoxyl group.

Hydrothermal carbonization: Process water characterization and effects of water recirculation

Poplar wood chips were treated hydrothermally and the increase of process efficiency by water recirculation was examined. About 15% of the carbon in the biomass was dissolved in the liquid phase when biomass was treated in de-ionized water at 220 °C for 4 h. The dissolved organic matter contained oxygen and was partly aerobically biodegradable. About 30-50% of the total organic carbon originated from organic acids. A polar and aromatic fraction was extracted and a major portion of the organic load was of higher molecular weight. By process water recirculation organic acids in the liquid phase concentrated and catalyzed dehydration reactions. As a consequence, functional groups in hydrothermally synthesized coal declined and dewaterability was enhanced. Recirculated reactive substances polymerized and formed additional solid substance. As a result, carbon and energetic yields of the produced coal rose to 84% and 82%, respectively.

Greenhouse gas mitigation potential of a second generation energy production system from short rotation poplar in Eastern Germany and its accompanied uncertainties

This study investigates the variance of the overall greenhouse gas mitigation potential of a complete second generation stationary bio-electricity production system, generated by poplar wood chips (Populus spec.) in Germany, using Monte Carlo simulations. We computed the GHG emissions as EB=(−0.034±0.021)kgCO2eMJ−1 (mean±SD) and the mitigation factor as MFB=(0.274±0.021)kgCO2eMJ−1 following a life cycle assessment-based approach. Additionally, avoided nitrous oxide (N2O) emissions due to land use change were considered in the assessment. The most important factor for the overall mitigation variability was the uncertainty of the organic carbon changes in the soil, followed by the variability of yields. The uncertainty of (i) direct N2O emissions from the poplar site or (ii) the reference rye site as well as (iii) the uncertainty of heat recovery percentage was of minor importance. Uncertainties in the global warming potentials of nitrous oxide and methane and in the transport distance were found to be irrelevant.The uncertainty of the GHG mitigation which was associated with this specific electricity generation by poplar wood chips gasification was significantly lower compared to the variability of another common bio-electricity system (biogas). Uncertainty implications seem to be system-specific and therefore should be analysed separately for each bioenergy pathway under consideration.

Startup and long-term performance of biotrickling filters packed with polyurethane foam and poplar wood chips treating a mixture of ethylmercaptan, H2S, and NH3

Treatment of a mixture of NH3, H2S, and ethylmercaptan (EM) was investigated for more than 15 months in two biotrickling filters packed with poplar wood chips and polyurethane foam. Inlet loads ranging from 5 to 10 g N-NH3 m−3 hr−1, from 5 to 16 g S-H2S m−3 hr−1, and from 0 to 5 g EM m−3 hr−1 were applied. During startup, the biotrickling filter packed with polyurethane foam was re-inoculated due to reduced biomass retention as well as a stronger effect of nitrogen compounds inhibition compared with the biotrickling filter packed with poplar wood. Accurate pH control between 7 and 7.5 favored pollutants abatement. In the long run, complete NH3 removal in the gas phase was achieved in both reactors, while H2S removal efficiencies exceeded 90%. EM abatement was significantly different in both reactors. A systematically lower elimination capacity was found in the polyurethane foam bioreactor. N fractions in the liquid phase proved that high nitrification rates were reached throughout steady-state operation in both bioreactors. CO2 production showed the extent of the organic packing material degradation, which allowed estimating its service lifetime in around 2 years. In the long run, the bioreactor packed with the organic packing material had a lower stability. However, an economic analysis indicated that poplar wood chips are a competitive alternative to inorganic packing materials in biotrickling filters. Implications: We provide new insights in the use of organic packing materials in biotrickling filters for the treatment of H2S, NH3, and mercaptans and compare them with polyurethane foam, a packing commonly used in biotrickling filters. We found interesting features related with the startup of the reactors and parameterized both the performance under steady-state conditions and the influence of the gas contact time. We provide relevant conclusions in the profitability of organic packing materials under a biotrickling filter configuration, which is infrequent but proven reliable from our research results. The report is useful to designers and users of this technology.

A two-stage pretreatment approach to maximise sugar yield and enhance reactive lignin recovery from poplar wood chips

A two-stage pretreatment approach, employing steam followed by organosolv treatment, was assessed for its ability to fractionate and recover most of the hemicellulose, lignin and cellulose components of poplar wood chips. A mild steaming stage was initially used to maximise hemicellulose sugar recovery, with 63% of the original xylan solubilised and recovered after this stage and close to 90% recovered in total. Rather than hindering subsequent organosolv delignification, the prior steam treatment enhanced lignin solubilisation with more than 66% of the original lignin removed after the two-stage pretreatment. The extracted lignin contained at least equal or greater amounts of functional groups as compared to the lignin solubilised after a single-stage organosolv pretreatment. More than 98% of the original cellulose was recovered after the two-stage pretreatment and 88% of the cellulose could be hydrolysed to glucose at enzyme loading of 5FPU/g cellulose after 72h.

Storage Problems of Poplar Chips from Short Rotation Plantations with Special Emphasis on Fungal Development

Abstract - There are several problems in storing wood chips freshly harvested from short rotation plantations, which result in quality losses as well as in dry matter and energy losses. The factors influencing the degradation of raw material are examined in this paper with special focus on fungal development. An excessive growth of fungi is connected to dry matter losses and also to an increased health risk during raw material handling. The following factors were measured during 6 months storage of poplar wood chips depending on particle size: box temperature, moisture content, pH-value, appearance of fungi in the storage and the concentration of fungal particles in the air. The results show a close connection between particle size, temperature and attack of fungi. During the storage mesophilic and termophilic species of the genera Alternaria, Aspergillus, Cladosporium, Mucor and Penicillium appeared. The concentration of fungal particles is the highest for fine chips and decreases in bigger particles. There was a special focus on the investigation of the properties of coarse chips (G 50), which represent a good compromise between handling, storage losses and health risk due to fungal development.

The Metagenome of an Anaerobic Microbial Community Decomposing Poplar Wood Chips

This study describes the composition and metabolic potential of a lignocellulosic biomass degrading community that decays poplar wood chips under anaerobic conditions. We examined the community that developed on poplar biomass in a non-aerated bioreactor over the course of a year, with no microbial inoculation other than the naturally occurring organisms on the woody material. The composition of this community contrasts in important ways with biomass-degrading communities associated with higher organisms, which have evolved over millions of years into a symbiotic relationship. Both mammalian and insect hosts provide partial size reduction, chemical treatments (low or high pH environments), and complex enzymatic ‘secretomes’ that improve microbial access to cell wall polymers. We hypothesized that in order to efficiently degrade coarse untreated biomass, a spontaneously assembled free-living community must both employ alternative strategies, such as enzymatic lignin depolymerization, for accessing hemicellulose and cellulose and have a much broader metabolic potential than host-associated communities. This would suggest that such a community would make a valuable resource for finding new catalytic functions involved in biomass decomposition and gaining new insight into the poorly understood process of anaerobic lignin depolymerization. Therefore, in addition to determining the major players in this community, our work specifically aimed at identifying functions potentially involved in the depolymerization of cellulose, hemicelluloses, and lignin, and to assign specific roles to the prevalent community members in the collaborative process of biomass decomposition. A bacterium similar to Magnetospirillum was identified among the dominant community members, which could play a key role in the anaerobic breakdown of aromatic compounds. We suggest that these compounds are released from the lignin fraction in poplar hardwood during the decay process, which would point to lignin-modification or depolymerization under anaerobic conditions.

Simultaneous Removal of H2S, NH3, and Ethyl Mercaptan in Biotrickling Filters Packed with Poplar Wood and Polyurethane Foam: Impact of pH During Startup and Crossed Effects Evaluation

The present work discusses the startup and operation of different biotrickling filters during the simultaneous removal of NH3, H2S, and ethyl mercaptan (EM) for odor control, focusing on (a) the impact of pH control in the stability of the nitrification processes during reactor startup and (b) the crossed effects among selected pollutants and their by-products. Two biotrickling filters were packed with poplar wood chips (R1 and R2A), while a third reactor was packed with polyurethane foam (R2B). R2A and R2B presented a pH control system, whereas R1 did not. Loads of 2–10 g N–NH3 m−3 h−1, 5–16 g S–H2S m−3 h−1, and 1–6 g EM m−3 h−1 were supplied to the bioreactors. The presence of a pH control loop in R2A and R2B proved to be crucial to avoid long startup periods and bioreactors malfunctioning due to biological activity inhibition. In addition, the impact of the presence of different concentrations of a series of N species (NH4+, NO2−, and NO3−) and S species (SO42− and S2−) on the performance of the two biotrickling filters was studied by increasing their load to the reactors. Sulfide oxidation proved to be the most resilient process, since it was not affected in any of the experiments, while nitrification and EM removal were severely affected. In particular, the latter was affected by SO42− and NO2−, while nitrification was significantly affected by NH4+. The biotrickling filter packed with polyurethane foam was more sensitive to crossed effects than the biotrickling filter packed with poplar wood chips.

Two-Stage Acid-Catalyzed Conversion of Carbohydrates into Levulinic Acid

In this paper, we report on a two-stage acid-catalytic conversion of carbohydrates from hybrid poplar wood chips into levulinic acid (LA), a renewable platform chemical which can be used for fuels and chemicals. It was hypothesized that under the harsh acid conditions utilized during LA production, the pentose fraction in biomass would first form furfurals which would then polymerize with saccharides forming humins. These reactions would both reduce any potential value from the pentose fraction as well as lower the levulinic acid yield. To test this idea, a two-stage conversion process was designed starting with a mild acid extraction to remove the majority of the pentoses while maintaining the hexose sugars in a solid form utilizing previously described optimized conditions. LA was then produced by subjecting the extracted solids to a second more severe step. The temperature, time, acid concentration, and a liquor-to-wood ratio were varied and modeled to find the optimal conditions. The best conditions were high acid concentration, high temperature, and low substrate consistency, which produced a maximum molar yield of 66% based on the hexose content or 17.5 wt % based of the initial biomass. A comparison of this two-stage process to a single-stage process without the pentose extraction was performed both with biomass and model compounds, which indicated no pentose or furfural in the product stream and a marked molar yield decrease in LA yield from the presence of pentose sugars, validating our initial hypothesis.

Tracking dynamics of plant biomass composting by changes in substrate structure, microbial community, and enzyme activity

BackgroundUnderstanding the dynamics of the microbial communities that, along with their secreted enzymes, are involved in the natural process of biomass composting may hold the key to breaking the major bottleneck in biomass-to-biofuels conversion technology, which is the still-costly deconstruction of polymeric biomass carbohydrates to fermentable sugars.However, the complexity of both the structure of plant biomass and its counterpart microbial degradation communities makes it difficult to investigate the composting process.ResultsIn this study, a composter was set up with a mix of yellow poplar (Liriodendron tulipifera) wood-chips and mown lawn grass clippings (85:15 in dry-weight) and used as a model system. The microbial rDNA abundance data obtained from analyzing weekly-withdrawn composted samples suggested population-shifts from bacteria-dominated to fungus-dominated communities. Further analyses by an array of optical microscopic, transcriptional and enzyme-activity techniques yielded correlated results, suggesting that such population shifts occurred along with early removal of hemicellulose followed by attack on the consequently uncovered cellulose as the composting progressed.ConclusionThe observed shifts in dominance by representative microbial groups, along with the observed different patterns in the gene expression and enzymatic activities between cellulases, hemicellulases, and ligninases during the composting process, provide new perspectives for biomass-derived biotechnology such as consolidated bioprocessing (CBP) and solid-state fermentation for the production of cellulolytic enzymes and biofuels.

Cellulose extraction from wood chip in an ionic liquid 1-allyl-3-methylimidazolium chloride (AmimCl)

In the present study, 1-allyl-3-methylimidazolium chloride (AmimCl), an ionic liquid (IL), was used to extract cellulose from pine, poplar, Chinese parasol, and catalpa wood chips. Results show that pine is the most suitable wood species for cellulose extraction with ILs. Its cellulose extraction rate can reach as high as 62% under optimized conditions and its cellulose content is as high as 85% when DMSO/water is used as the precipitant. The dissolution process can be clearly observed by hot stage optical microscopy, and the reaction time can be significantly reduced by microwave irradiation. 13C CP/MAS NMR, FTIR, XRD, and SEM were used to analyze the cellulose-rich extracts of pine. Results show that IL dissolves pine wood by destroying inter and intramolecular hydrogen bonds between lignocelluloses. The major component of pine extract is cellulose with a homogeneous and dense structure. After extraction, AmimCl can be easily recycled and reused.