Purity Of Cellulose Research Articles

Production of high-quality dissolving pulp from eucalyptus wood chips using deep eutectic solvent and elemental chlorine-free bleaching

Deep eutectic solvent (DES) provides promising alternatives to conventional pulping and cellulose purification with significantly lower energy consumption and impacts on the environment. In this work, choline chloride – lactic acid (ChCl-LA DES) pulping of eucalyptus wood chips combined with several ECF bleaching sequences was investigated to produce high-grade dissolving pulps. Initially, the dependency of DES pulping yield and delignification efficiency on the moisture content (MC) of used wood chips was evaluated. The results exhibited the crucial influence of the MC of wood chips on the delignification efficiency of DES pulping. DES pulping under optimized conditions resulted in an unbleached pulp with kappa number of 42, relatively high screened yield 48.1% and viscosity 796 cm3/g, as well as very low hemicellulose content, typically less than 3.8%. Further purification of the obtained pulp using D-Ep-D and OO-D-Ep-D bleaching sequences produces several dissolving pulps characterized by a high viscosity 695 cm3/g and brightness 89.5% ISO, indicating low degradation of cellulose during DES pulping. DES pulping exhibited considerable potential to remove the hemicelluloses from wood chips and produce high-quality dissolving pulps. This could be attained through shorter pulping operations conducted at a lower temperature and a higher screened yield compared to current dissolving pulp production operations.

Cellulose nanocrystals from marine algae Cladophora glomerata by using microwave-assisted extraction

Algae of the order Cladophorales are the source of a unique nanocellulose with high crystallinity and a large aspect ratio, enabling broad surface modification. Cellulose nanocrystals (CNCs) are obtained via acid hydrolysis of nanocellulose, which is highly crystalline. However, the production of CNCs from Cladophorales algae is limited and still uses a conventional heating method. Thus, this study aimed to develop a microwave-assisted extraction (MAE) method for fast and efficient extraction of CNCs from Cladophora glomerata algae. Additionally, we replaced the use of hypochlorite with H2O2, which is more environmentally friendly, and compared the CNCs obtained from the conventional methods with our new method. The functional structure of CNCs was confirmed by Fourier-transform infrared spectroscopy. Single-step H2O2 bleaching with MAE yielded the smallest-sized CNCs. Our developed method resulted in the production of CNCs with a high crystallinity index, high thermal stability, and high purity of native cellulose. Additionally, none of the CNCs were toxic to primary normal human dermal fibroblasts. The properties of the isolated CNCs may make them useful materials in pharmaceutical and cosmetic formulations.

Organic acid-assisted organosolv fractionation of sawdust and using the fractionated lignin to prepare activated carbon pellets for high-temperature applications

In present, activated carbon (AC) pellets that are commonly prepared by petroleum-based binders have been used to control NOx, SOx, and volatile organic compounds (VOCs) emissions in the iron/steel industry. However, the use of petroleum-based binders leads to great challenges toward sustainability and environment. Alternatively, lignin as a natural bio-binder derived from biomass and organic waste can act as a potential additive for preparing AC pellets. Therefore, in this study, pinewood sawdust was initially fractionated into crude cellulose and lignin by organosolv fractionation method at 90–120 °C for 180 min in an acetic acid/formic acid/water mixed solvent of 3/5/2, 3/6/1, and 5/4/1, vol%/vol%/vol%. Afterward, the fractionated crude lignin was used as bio-additive to substitute 50 wt% of petroleum-derived phenol to synthesize phenol-formaldehyde resole resins (PLPF) and compared with those prepared using 100% petroleum-derived phenol resole resins (PF). PLPF and PF resins were further fabricated to AC pellets by thermal treatment/curing at 150 °C and different loadings of resins (i.e., 10–50 wt%), followed by carbonization at 400 and 700 °C. In the fractionation, it was found that temperature played a role in determining the yield and purity of crude cellulose and lignin, while the effect of solvent composition was insignificant. PLPF resins (loading of 50 wt%)-based AC pellets obtained from thermal treatment at 150 °C followed by carbonization at 400 °C showed a relatively higher compressive strength, which meets the national standard and could ensure their uses as an emission control method in the iron/steel industry. Overall, it can be concluded that lignin-derived from woody biomass by organosolv fractionation in acetic acid/formic acid/water mixture is an alternative bio-binder to prepare AC pellets for emission control at high temperatures.

Cellulose Isolation and Characterization of Green Seaweed C. Lentillifera from Halmahera, Indonesia

Caulerpa lentillifera or known as sea grapes is a type of green seaweed which is rich of nutritional components and widespread in the tropical regions in Asia, including Indonesia. Moreover, C. lentillifera contains of polysaccharides, such as cellulose which has the potential to various applications. In this study, C. lentillifera collected from Halmahera, Indonesia was determined for its chemical compositions (moisture, ash, extractives, hemicellulose, α-cellulose contents) and was extracted to obtain cellulose. Isolation of cellulose from C. lentillifera was done by soxhlet extracted using ethanol-benzene solvent to remove extractives, boiling to increase the amount of cellulose extracted, H2O2 bleaching to eliminate any remaining pigments and other contaminants, and freeze drying to get coarse powder of cellulose. The moisture content, ash, extractives, hemicellulose, α-cellulose of C. lentillifera were 11.94%, 31.62%, 11.53%, 35.57%, and 7.95%, respectively. The yield of cellulose obtained was 31.13% based on seaweed dry weight. FE-SEM (Field Emission-Scanning Electron Microscopy) analysis of C. lentillifera showed colonies of diatoms in elliptical shapes. FTIR (Fourier Transform Infrared) measurements indicating cellulose purity after extraction process. X-Ray Diffraction (XRD) analysis resulted some peaks of salt crystals in C. lentillifera and cellulose of C. lentillifera in amorphous form. After extraction, the crystallinity index of cellulose obtained was 37.3%.

Subcritical Water Extraction for Valorisation of Almond Skin from Almond Industrial Processing.

Almond skin (AS) is an agro-industrial residue from almond processing that has a high potential for valorisation. In this study, subcritical water extraction (SWE) was applied at two temperatures (160 and 180 °C) to obtain phenolic-rich extracts (water-soluble fraction) and cellulose fibres (insoluble fraction) from AS. The extraction conditions affected the composition and properties of both valorised fractions. The dry extracts obtained at 180 °C were richer in phenolics (161 vs. 101 mg GAE. g-1 defatted almond skin (DAS)), with greater antioxidant potential (1.063 vs. 1.490 mg DAS.mg-1 DPPH) and showed greater antibacterial effect (lower MIC values) against L. innocua (34 vs. 90 mg·mL-1) and E. coli (48 vs. 90 mg·mL-1) than those obtained at 160 °C, despite the lower total solid yield (21 vs. 29%) obtained in the SWE process. The purification of cellulose from the SWE residues, using hydrogen peroxide (H2O2), revealed that AS is not a good source of cellulose material since the bleached fractions showed low yields (20-21%) and low cellulose purity (40-50%), even after four bleaching cycles (1 h) at pH 12 and 8% H2O2. Nevertheless, the application of a green, scalable, and toxic solvent-free SWE process was highly useful for obtaining AS bioactive extracts for different food, cosmetic, or pharmaceutical applications.

Preparation and characterization of cellulose nanocrystals with high stability from okara by green solvent pretreatment assisted TEMPO oxidation

Because the traditional preparation methods of cellulose nanocrystals (CNCs) involve chemical pollution issues, in this study, two typical green solvents, alkali/urea solvent (AUS) and deep-eutectic solvent (DES), were used to dissolve insoluble soybean fibers (ISF) extracted from okara and prepare regenerated CNCs (AUS/CNC and DES/CNC), which were further modified by TEMPO oxidation (AUS/T-CNC and DES/T-CNC). The recoveries of AUS and DES were 82.58 % and 84.00 %, respectively. Chemical composition analysis showed high cellulose purity (>95 %) of the regenerated CNCs. FTIR, XRD and 13C NMR analysis indicated the cellulose structure and polymorph of CNCs. Thermal analysis revealed that the maximum degradation peak of regenerated CNC shifted to a lower temperature. AFM revealed that CNCs exhibited rod-like fiber structures, while AUS-pretreated CNCs exhibited some special spherical fibers. TEMPO oxidation showed an enhancement effect on the characteristics of AUS/T-CNC and DES/T-CNC; DES/T-CNC exhibited higher stability and apparent viscosity than AUS/T-CNC. The DES/T-CNC-based cryogel displayed a higher adsorption capacity for anthocyanin (0.40 g/g) and curcumin (1.09 g/g) with good controlled release capacity. These results indicated that green solvent pretreatment-assisted TEMPO oxidation is a new environmentally friendly and low-cost method for the preparation of CNCs and shows excellent potential in the field of drug loading and controlled release.

Improved dsRNA isolation and purification method validated by viral dsRNA detection using novel primers in Saccharomyces cerevisiae

Accurate genomic sequencing demands high-quality double-stranded RNA (dsRNA). Existing methods for dsRNA extraction from yeast, fungi, and plants primarily rely on cellulose, suitable only for small volume extractions, or the time-consuming lithium chloride precipitation. To streamline the traditional phenol-chloroform-based dsRNA extraction method, the main challenge is the reduction of mitochondrial DNA (mtDNA) and Single Stranded RNA (ssRNA) to no detectable levels after gel electrophoresis. This challenge is successfully addressed through the modified approach described here, involving phenol extraction at low pH, followed by the addition of ammonium sulfate to the aqueous buffer. The dsRNA isolated using this novel method exhibits comparable quality to that obtained through cellulose purification, and it is readily amenable to RT-PCR. Moreover, a single batch of yeast cell RNA isolation requires only 2-3 h of hands-on time, thus simplifying and expediting the process significantly.•Buffers were redesigned from [32,33,35].•No DNASE, Ribonuclease A or beads were used during the purification.•Simple and inexpensive dsRNA extraction and purification method is described.

Microwave-assisted formic acid/cold caustic extraction for separation of cellulose and hemicellulose from biomass

Effective separation of cellulose and hemicellulose from lignocellulosic biomass is an essential step for creating high-value products. In this study, a modified treatment process was proposed for cellulose purification via microwave-assisted formic acid catalytic hydrolysis followed by cold caustic extraction. The sugar content in the extract was determined using UV spectrophotometer and dual-wavelength visible spectrophotometry. Combined microwave-assisted formic acid (M-FA) with cold caustic extraction (CCE) treatments achieved rapid separation and removal of hemicelluloses from waste hardwood pulp fibers. The hemicelluloses content decreased from 28.6% to 2.3%, and the lignin content changed from 27.8% to 6.1%, which resulted in a maximal cellulose content of 91.5% under the optimal M-FA/CCE treatment conditions. In addition, the crystallinity index of pulp fibers increased from 54.3% to 67.1%, and the initial decomposition temperature decreased from 335.4 to 270.2 °C with the decrease of hemicellulose and lignin content. The modified process provided a sustainable and effective method for hemicellulose separation and lignin removal from cellulosic fibers.

Simple method for obtaining regenerated cellulose nanoparticles from delignified coffee parchment, and their use in fabricating blended films

Coffee parchment is one of the residues generated in coffee processing and has been poorly explored for value-added applications. It has been reported that coffee parchment has a high cellulose content (40–49%). Cellulose has been studied in many fields and specifically regenerated cellulose has been explored for many applications. Then, in this work a simple method for obtaining regenerated cellulose nanoparticles (RCNPs) from delignified coffee parchment, was determined. A complete physicochemical characterization of RCNPs obtained is presented, FTIR showed high cellulose purity, and XRD analysis showed high crystallinity of cellulose II. TEM images revealed that nanoparticles have spherical morphology. TGA showed good thermal stability and DLS allowed to determine the stability of suspension and the Z-average of the particles. The application of RCNPs on film formation was also evaluated when blended with PVA and Glycerol showing good mechanical properties with potential application on food packing.

Synthesis and Characterization of Bamboo Employed Environmentally Friendly Cellulose Nanofibrils Reinforced Natural Rubber Composites with Uncompromised Mechanical Properties

In this study, high-purity cellulose nanofibrils (CNFs) were environmentally friendly extracted from natural bamboo. Physical, chemical, and mechanical treatments were comprehensively investigated, and then ensembled to effectively and efficiently remove lignin and hemicellulose with low energy from raw bamboo fibers, which combine microwave liquefaction, hydrogen peroxide-acetic acid delignification, alkaline treatment, and along with acid hydrolysis. This was able to allow for the extraction of CNFs. Compositional analysis, Fourier-transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and thermogravimetric analysis were performed to investigate and confirm the successful removal of undesirable lignin and hemicellulose. The resultant cellulose fibers were then subjected to a mechanical treatment to obtain the cellulose nanofibrils. It was found that the obtained CNFs have an average diameter of 13 nm with a cellulose purity of 94.52%. Without any further surface modification, the incorporation of bamboo-based CNFs into natural rubber (NR) exhibits significant improvement in their mechanical properties including modulus (~66.67%), tensile strength (~120.83%), toughness (~139.34%), and elongation at break (~31.41%). Interestingly, there is no compromise between tensile strength and elongation at break for the nanocomposites. DMA results also showed that both storage and loss moduli were dramatically enhanced over those of neat NR in their glassy region, which is typically unusual. This study can show, if optimized for material extraction, the great promise to the potential use of natural materials to develop environmentally friendly composites with multi-functionality in a variety of real-world engineering structural applications.

Improving Pulping Performance as Well as Reducing Consumption and Increasing Efficiency via Microbial Consortium Pretreating Bamboo

The bio-refining process of bamboo is more challenging compared to wood due to its dense and stabilized complex polymer structure, as well as its abundance of degradation-resistant components. Consequently, the bio-refining of bamboo requires more energy and time consumption compared to the bio-refining of wood. In this study, co-cultured microorganisms were utilized for the pretreatment of bamboo to improve pulping performance, reduce consumption, and increase efficiency. These microorganisms were constructed by combining environmental microorganisms found in bamboo pulp with Bacillus sp. that were self-screened. The results of 16S rRNA analysis showed that the genera Proteobacteria, Firmicutes, Bacteroidota, and Actinobacteriota gradually became dominant during the treatment process. Additionally, the PICRUSt results indicated that the co-culture microbial consortium C strategy strengthened key enzyme activities related to the degradation of bamboo lignocelluloses. The microbial consortium pretreatment resulted in removing lignin and hemicellulose at rates of 21.96% and 26.21%, respectively. This process also caused a decrease in the crystalline index, indicating the presence of disordered crystalline regions. This change was beneficial for the subsequent Kraft pulping process. Compared to the conventional bamboo pulp, the yield of pretreated bamboo pulp increased slightly, while the cellulose purity and paper properties were significantly superior. The obtained Kraft pulp, which underwent microbiological pretreatment, met the requirements for superior Kraft pulp products despite a 65 min decrease in cooking time and a 10 °C decline in maximum cooking temperature. This study proves that co-cultured microbial consortium used for pretreating bamboo are beneficial for bamboo Kraft pulping. This approach can be considered environmentally friendly and leads to energy saving and cost reduction in bamboo bio-refining processes.

Extraction methods and characterization of cellulose fractions from a sugarcane by-product for potential industry applications

Sugarcane bagasse, the major by-product of the sugarcane industry, can be used to produce valuable materials such as cellulose or cellulose-based materials. In order to obtain more accessible and purified cellulose, pretreatment processes of lignocellulosic feedstocks are applied to decompose the complex cellulose-lignin-hemicellulose matrix, which facilitates access to isolated compounds. The influence of various autohydrolysis conditions, alkaline sulfite extraction and bleaching were evaluated in terms of extract yield, chemical profile and structural properties upon a solid fraction rich in cellulose. Among the treatments applied, autohydrolysis at 170 °C for 1 h followed by a bleaching step was the treatment that presented the best results in terms of cellulose purity (77.8%), crystallinity (73.4%), whiteness and glucose production by enzymatic hydrolysis, when compared with the non-treated fraction. The combination of autohydrolysis with a totally chlorine free bleaching step showed as a promising eco-friendliness alternative to obtain a white and solid fraction rich in cellulose, thus contributing to the valorization of this by-product.

Influence of the cellulose purification process on the properties of aerogels obtained from rice straw

Cellulose aerogels were obtained from purified rice straw cellulose fibres (CF) by applying different extraction methods: the conventional alkaline treatment (ALK) and alternative aqueous extraction based on the ultrasound combined with reflux heating (USHT) and subcritical water extraction (SWE) (160 and 180 °C). The composition and properties of the CFs were significantly affected by the purification process. The USHT treatment was as efficient as the ALK at eliminating the silica content, but the fibres maintained a notable ratio of hemicellulose (∼16 %). The SWE treatments were not so effective at removing silica (15 %) but greatly promoted the selective extraction of hemicellulose, especially at 180 °C (3 %). The CF compositional differences affected their hydrogel formation capacity and the properties of aerogels. A higher hemicellulose content in the CF led to better-structured hydrogels with better water-holding capacity, while the aerogels exhibited a more cohesive structure with thicker walls, higher porosity (99 %) and water vapour sorption capacity, but lower liquid water retention capacity (0.2 g/g). The residual silica content also interfered with the hydrogel and aerogel formation, giving rise to less structured hydrogels and more fibrous aerogels, with lower porosity (97–98 %).

Broadening the product portfolio with cellulose and lignin nanoparticles in an elephant grass biorefinery

AbstractCellulose and lignin nanoparticles are high‐value‐added products obtained from lignocellulosic biomasses through several steps of cellulose purification and lignin extraction. These steps drastically reduce the potential feedstock revenue when carried out as stand‐alone methodologies. To increase biomass yields, we describe here a strategy to design a biorefinery focused on producing cellulose and lignin nanoparticles as main products, but also aim to recover and benefit from other biomass components using only water‐based processes. Sequential pressurized liquid extractions and diluted acid and alkaline treatments were carried out to fractionate elephant grass biomass, yielding (for every 100 g of biomass): 30 g of cellulose pulp (converted to 9 g of cellulose nanocrystals and 9 g of cellulose nanofibers); 10 g of lignin (used to produce 8.5 g of stable colloidal lignin nanoparticles by probe‐sonication in water); 7.5 g of extractives (e.g. sterols and phenolics) and 23 g of xylose (converted to 4.1 g of furfural). Alternatively, to allow for the flexible use of the cellulose fraction in the proposed biorefinery, 22 g of glucose could be produced by enzymatic hydrolysis. The results demonstrate that water‐based processes are suitable for a holistic use of biomass, providing a comprehensive set of high‐value‐added co‐products that are renewable and cost‐effective chemical, cosmetic, food, polymer and pharmaceutical solutions.

Extraction of high-quality grade cellulose and cellulose nanocrystals from different lignocellulosic agri-food wastes

IntroductionPrompted by the increasing need for an intensified valorization of agri-food waste, in this work a three-step chemical procedure was used to extract high-purity cellulose from garlic stalk, corncob, and giant cane cut-up by a sequential removal of hemicellulose, lignin, ash, and organic compounds. Cellulose nanocrystals of potential interest for nanocomposite applications were then obtained through acid hydrolysis.MethodsThe purity of the cellulose was determined employing Nuclear Magnetic Resonance and infrared spectroscopy, whereas dynamic light scattering, optical, atomic force microscopy, and transmission electron microscopy were used for morphological characterization. The high purity and crystallinity of cellulose was confirmed by comparison with the ultra-pure bacterial cellulose originating from K. sucrofermentans, irrespective of the waste used.Results and discussionAt the end of the extraction procedure, cellulose yields of 35.73, 37.15, and 39.10%, for garlic stalk, corncob, and giant cane cut-up, respectively, were achieved. Dynamic light scattering and atomic force microscopy analyses showed that the length of the whisker-like nanocrystals depended on the raw material (from ~100 nm up to > 2μm), while the final yield was ~40–50% for all three wastes. The versatility and effectiveness of the method here proposed can be profitably used for a wide range of agro-waste feedstocks.

High Cellulose Purity by Acid Hydrolysis Pretreatment on Kenaf Outer Bast

Acid hydrolysis treatment of kenaf outer bast fiber can produce pure cellulose content and hydrolyzed hemicellulose to monosaccharides. The effects of various reaction temperatures (110–130 °C), acid concentrations of sulfuric acid (0.25–1.00 N), and reaction times (60–120 min) were investigated as the optimum condition to gain pure cellulose content. A 1H NMR spectroscopy was used to analyze the carbohydrate content in the reaction of acid hydrolysis treatment. The results showed that optimum conditions for acid hydrolysis refer to two treatment prospects. First, a higher reaction temperature of 130 °C was necessary to increase the reaction for the hydrolyzes of hemicellulose—the high yield content produced by 0.25 N sulfuric acid with a short reaction time of 60 min. to improve the purity of cellulose, provided by the high sulfuric acid solution of 1.00 N for 120 min. Hemicellulose was hydrolyzed at almost 100% based on the two optimal conditions. The analysis revealed that a high temperature of acid hydrolysis was the primary treatment to hydrolyze hemicellulose to increase high pure cellulose from the kenaf outer bast fiber.

Feasibility for the preparation of aerogels with celluloses extracted mildly from waste palm leaves

Abstract Reasonable use and disposal of agricultural and forestry wastes become an urgent focus of attention with the dangers of pollution and squandering. In this paper, palm leaves, a typical kind of cellulose-rich agricultural and forestry waste, were attempted to prepare high-valued porous aerogels with cellulose by a short and mild extraction followed by the process of cross-linking with polyvinyl alcohol (PVA). Scanning electron microscope (SEM), Fourier transform-infrared (FTIR), X-ray diffraction (XRD), Bruno-Emmett-Teller (BET), and thermogravimetric analysis (TGA) were applied to examine their structures, chemical composition, and performance compared with hardwood cellulose aerogels. The results showed that palm leaf cellulose could be extracted friendly under mild extraction of 5% NaOH solution for 7 h, following 10% H2O2 solution for 8 h at 80 °C, which inhibits effectively the alkaline hydrolysis of cellulose with the extraction rate of 35.25%, the cellulose purity of 87.12%, and crystallinity of 69.9%. Compared with hardwood cellulose aerogel, the prepared environmentally friendly and recyclable palm leaf cellulose aerogel is a promising application material with similar ultra-low density, high porosity, specific surface area, thermal stability, and better compression resilience, which provides a new technical direction for the high-value application of agricultural and forestry wastes.

Rapid and massive fractionation of hemicelluloses for purifying cellulose at room temperature by tetramethylammonium hydroxide

The fractionation of hemicelluloses is a promising method to improve the comprehensive utilization of lignocellulosic biomass. However, the effective fractionation of hemicelluloses is always limited by the structural complexity and easy degradability. In this study, tetramethylammonium hydroxide (TMAH) was developed to fractionate hemicelluloses from poplar holocellulose with high molecular weights and high yields at room temperature. Approximately 90% of hemicelluloses could be dissolved at room temperature in 1 h, and the yield was up to 81.9%. Compared with the fractionation using NaOH solution, the hemicelluloses isolated by TMAH solvent showed a more complete structure and higher purity. Meanwhile, the retention rate of cellulose after treatment with TMAH was up to 90.2%, and the crystal structure of cellulose in the residues was practically unchanged. Moreover, the TMAH solvent could be recycled to fractionate hemicelluloses. The work provides an elegant and significantly efficient method towards hemicelluloses fractionation and cellulose purification.

Effect of delignification and bleaching stages on cellulose purity of oil palm empty fruit bunches

Oil palm empty fruit bunches (OPEFB) have not been properly utilized by most palm oil mills and communities in Indonesia. The processing and utilization of OPEFB by palm oil mills are still limited. Due to high cellulose contents, it potentially made into various bioproducts, especially as biomaterials. Therefore, a proper extraction technology is needed to obtain a high level of cellulose purity because alkaline treatment can solely remove a part of hemicellulose and lignin. A higher cellulose content can be obtained by further chemical treatments through the bleaching process. However, no information regarding the difference of the isolation performance method to produce cellulose purity by delignification first or vice versa bleaching as an initial stage. The research determined the purity of EFB cellulose with differences in the sequence of bleaching and alkaline delignification stages. The three methods were carried, namely the first method by bleaching using sodium chlorite 3% two times, followed by delignification of NaOH 10% at room temperature, second method with the same conditions but delignification of NaOH 10% at a temperature of 70-80°C and third method by delignification and continued bleaching under the same conditions. The results showed the bleaching method of sodium chlorite of 2 cycles and continued by alkaline delignification (NaOH 10%) at room temperature resulted in higher cellulose purity than other methods. The FTIR test results indicated the detection of the C-O functional group at a wavelength of 1196 cm-1 and the C-H functional group at a wavelength of 2967 cm-1.

Visualization of wood cell structure during cellulose purification via high resolution X-ray CT and spectroscopy

Wood is a heterogeneous material with multiple scales. Revealing the three-dimensional structure of wood tissue in multiple dimensions works as a prerequisite for the reorganization, modification and high-value utilization of wood. By adopting high resolution X-ray micro computed tomography (XμCT), the three-dimensional structural changes during cellulose purification were reconstructed. In the meantime, the changing process in the chemical composition of wood cell wall was demonstrated in situ using laser Raman spectroscopy imaging technology. Moreover, cellular changes on a two-dimensional scale were observed by ordinary optical, fluorescence, and polarizing microscopes respectively. XμCT results indicated that the disruption of the cell structure of chinese fir (Cunninghamia lanceolata (Lamb.) Hook.) by purification treatment started between the diameter walls of the tracheids, while that of the poplar (Populus sp.) cell structure started between the vessels or between the vessels and the wood rays. Such kind of disruption in cell structure was more pronounced after the hemicellulose was removed, with adjacent cells scattered and deformed. In the first step of matrix removal, the cell wall got thinner primarily out of lignin removal, while in the process of hemicellulose removal, the cell wall swelled with the lye. The Raman images illustrated that the distribution of purified cellulose in the cell wall was related to the degree of cell disruption. In undeformed cell walls, the cellulose was evenly distributed, whereas in shrunken and deformed cell walls, it was unevenly scattered.