Purity Of Cellulose Research Articles

The Impacts of HCl Concentration and Length of Time to Mesocarp in Producing of Bioethanol

Studies about renewable energy are evolved continuously to decrease the needs of fuel oils that were diminished. One of the alternative energy sources that can be evolved is bioethanol due to the high amount of oxygen component in it hence it can be combustible and eco-friendly. Mesocarp is farming and trading waste of Cocos Nucifera (Coconut) that contains 40% lignin, 44,4% cellulose, and 15% hemicellulose. Delignification is a process of removing lignin from the materials thus it can produce the high purity of cellulose. As long as this, there were numerous studies that researched about lignocellulose biomass, however the least studies researched the impact of using delignification. Thereby, this study was done for figuring out the impact of HCl concentration and length of time to the decreased lignin content and the quality of bioethanol. The points of impacts that being focused on were 1M, 2M, and 3M HCl concentration, whereas the points of length of time impacts were about 60 minutes, 90 minutes, 120 minutes, 150 minutes, and 180 minutes. The decreased lignin content that was obtained is about 18,5% and the finest bioethanol is 97,38 %, 15oC for flash point, 3,8402 cPs for viscosity, and 0,8252 gr/cm3 for density from delignification using 3M HCl for about 150 minutes. Greater HCl concentration to delignification, greater quality of bioethanol that is produced, therefore can be applied to alternative fuel oils for vehicle.

Study of a Novel Biorefining Method for Obtaining 2-Furaldehyde, Acetic Acid and Pulp from Birch Wood

Necessity for reduction of greenhouse gases emissions, the growing demand for improvement of biorefinery technologies and the development of new biorefining concepts, oblige us as a society, mainly scientists, to develop novel biorefinery approaches. The aim of this research was to comprehensively characterize lignocellulosic biomass that was obtained after 2-furaldehyde production, in terms of further valorization of this resource. This research shows that birch wood chips can be used in the new biorefinery processing chain for production of 2-furaldehyde, acetic acid and subsequent cellulose pulp obtaining, using thermomechanical and alkaline peroxide mechanical pulping process. In addition, obtained lignocellulosic residue was also characterized. Unique bench-scale reactor system was used to obtain a lignocellulosic material without pentoses and with maximum preservation of cellulose fiber for further use. Studies on the deacetylation and dehydration of birch wood hemicelluloses of pentose monosaccharides to 2-furaldehyde and acetic acid using orthophosphoric acid as a catalyst were carried out. Results showed that depending on the used pretreatment conditions the 2-furaldehyde yield was from 0.04 to 10.84 % o.d.m., the acetic acid yield was from 0.51 to 6.50 % o.d.m. and the lignocellulose residue yield was from 68.13 to 98.07 % o.d.m. with minimal content of admixtures. In addition, experimentally the optimal 2-furaldehyde production conditions regarding to purity and usability of cellulose in leftover of lignocellulosic material were developed. Best results in terms of both 2-furaldehyde yield and purity of residual lignocellulose were obtained in experiment where catalyst concentration was 70%, catalyst amount 4 wt.%, reaction temperature 175 °C and treatment time 60 min. By performing alkaline peroxide mechanical pulping of the relevant LC residue, it was possible to obtain pulp with tensile index comparable to standard printing paper, indicating that it is possible to perform stepwise 2-furaldehyde production with subsequent pulping to obtain various value added products.

Conversion of Sugarcane Trash to Nanocrystalline Cellulose and its Life Cycle Assessment

Sugarcane trash (SCT) is a promising, underutilized raw material for producing value-added bio-based materials. Nanocrystalline cellulose (NCC) production conditions were obtained from the experiment. On the other hand, bioethanol production conditions were retrieved from the secondary data. This study compared the environmental impact of SCT in NCC production to that of bioethanol. For NCC production, SCT was subjected to organosolv pretreatment (140, 160, or 180 °C) in a mixed solvent system (methyl isobutyl ketone (MIBK), ethanol, and water), bleached, and then hydrolyzed with different concentrations of sulfuric acid (50 and 58%) for varying times. Organosolv pretreatment at 180 °C removed 98.24 and 81.15% of the hemicellulose and lignin, respectively, resulting in 73.51 and 79.72% cellulose purity and recovery. In addition, bleaching increased the cellulose purity to 95.42%. Field Emission Transmission Electron Microscopy (FE-TEM) analysis showed that NCC’s small 2:1 elliptical particles were found at the hydrolysis of 50% H2SO4 for 45 min. The X-ray diffraction (XRD) pattern revealed 70% crystalline index values for NCC obtained from 50% H2SO4 with 45 min retention times. Then, the optimum conditions of NCC production were used for LCA analysis (Sigmapro software). The analysis included global warming, marine ecotoxicity, fresh water, and human carcinogenic toxicity. NCC production’s electricity consumption (freeze-dried step) was the highest environmental impact on LCA analysis.

Low-condensed lignin and high-purity cellulose production from poplar by synergistic deep eutectic solvent-hydrogenolysis pretreatment

This paper presented a green and environmentally friendly method to obtain lignin with a structure similar to milled wood lignin (MWL) and high-purity cellulose from biomass in a two-step process. The first step, maleic acid (MA), choline chloride (ChCl), and ethylene glycol (EG) ternary deep eutectic solvent (DES) pretreatment was performed to obtain lignin with less-condensed structure. The results showed that the obtained lignin had similar properties to MWL under the condition (MA/ChCl/EG = 1:5:15, 80°C, 10 h). The DES recovered still had good cycle performance. The second step, the cellulose-rich residue was hydrogenated with isopropanol-water solvent and Raney nickel to obtain high-purity cellulose. The results showed that the purity of cellulose obtained by catalytic hydrogenolysis was > 94%. The glucose yield after enzymatic hydrolysis was 243.72 mg/g, which was 14.7 times higher than the untreated poplar. Overall, this work was of great significance for the effective separation of biomass.

Application of non-thermal plasma as an alternative for purification of bacterial cellulose membranes

During the production of cellulose a purification process is applied, which is essential for its safe application in certain contexts, such as skin replacement, as it removes metabolites and bacterial cell debris. Currently, the most frequently adopted methodology is the immersion of the membranes in NaOH solution and this generates chemical residues. Also, the lack of consensus on the ideal methodology has led to discrepancies between results obtained by different authors. In the study reported herein, the action of non-thermal plasma (NTP) technology when applied in the bacterial cellulose (BC) purification process was investigated. The BC was synthesized using Gluconacetobacter hansenii. It was removed from the culture medium and immediately exposed to the NTP reactor in sterile distilled water for different treatment periods (10–30 min). The production capacity was determined and the BC obtained was subjected to physical-chemical characterization, morphological analysis, live/dead fluorescent microscopy and surface characterization via contact angle measurements. The results showed that after 15 min of treatment with NTP, no new membranes appeared when the BC samples were placed back in the culture medium. Micrographs of the membranes subjected to 10 min of plasma treatment showed bacteria or bacterial remnants (in both inner and outer areas) while after 15 min a significant decrease in bacterial cells was observed, mainly in the inner area. This demonstrates that the plasma can be used for the superficial and internal reduction of colonies present in BC membranes, to levels of almost complete elimination. The results reported herein demonstrate the potential of NTP application in the bacterial cellulose purification process, optimizing the production time and avoiding the generation of aggressive chemical residues.

Thermomechanical and Alkaline Peroxide Mechanical Pulping of Lignocellulose Residue Obtained from the 2-Furaldehyde Production Process.

The necessity for the reduction in greenhouse gas emissions, the growing demand for the improvement of biorefinery technologies, and the development of new biorefining concepts oblige us as a society, and particularly us, as scientists, to develop novel biorefinery approaches. The purpose of this study is to thoroughly evaluate the leftover lignocellulosic (LC) biomass obtained after the manufacture of 2-furaldehyde, with the intention of further valorizing this resource. This study demonstrates that by using thermomechanical and alkaline peroxide mechanical pulping techniques, birch wood chips can be used in the new biorefinery processing chain for the production of 2-furaraldehyde, acetic acid, and cellulose pulp. In addition, the obtained lignocellulosic residue is also characterized. To produce a lignocellulosic material without pentoses and with the greatest amount of cellulose fiber preserved for future use, a novel bench-scale reactor technology is used. Studies were conducted utilizing orthophosphoric acid as a catalyst to deacetylate and dehydrate pentose monosaccharides found in birch wood, converting them to 2-furaldehyde and acetic acid. The results showed that, with the least amount of admixtures, the yields of the initial feedstock’s oven-dried mass (o.d.m.) of 2-furaldehyde, acetic acid, and lignocellulose residue ranged from 0.04 to 10.84%, 0.51 to 6.50%, and 68.13 to 98.07%, respectively, depending on the pretreatment conditions utilized. The ideal 2-furaldehyde production conditions with reference to the purity and usability of cellulose in residual lignocellulosic material were also discovered through experimental testing. The experiment that produced the best results in terms of 2-furaldehyde yield and purity of residual lignocellulose used a catalyst concentration of 70%, a catalyst quantity of 4%, a reaction temperature of 175 °C, and a treatment period of 60 min. It was possible to create pulp with a tensile index similar to standard printing paper by mechanically pulping the necessary LC residue with alkaline peroxide, proving that stepwise 2-furaldehyde production may be carried out with subsequent pulping to provide a variety of value-added goods.

Effective Mild Ethanol-Based Organosolv Pre-Treatment for the Selective Valorization of Polysaccharides and Lignin from Agricultural and Forestry Residues

Organosolv pre-treatments aiming to selectively remove and depolymerise lignin and hemicellulose and yield an easily digestible cellulose fraction are one of the potential options for industrial implementation within the biorefinery concept. However, the use of high temperatures and/or high catalyst concentrations is still hindering its wide adoption. In this work, mild temperature organosolv processes (140 °C) that were either non-catalysed or catalysed with sulphuric or acetic acid were compared to standard similar conditions using ethanol-based organosolv for both wheat straw (WS) and eucalyptus wood residues (ERs) as agricultural and forestry-derived model raw materials, respectively. The experimental results demonstrated that high cellulose purities could be obtained for the catalysed ethanol-based processing of the WS, which resulted in high saccharification yields (>80%), conversely to the non-catalysed process, which only reached values close to 70%. For eucalyptus residues (ERs), the pulp yields obtained were lower than the values obtained for the WS, suggesting that the ERs were a more reactive material. Cellulose purity was higher than that obtained for the corresponding treatment for the WS, with the highest cellulose purity being obtained for the ethanol-based process catalysed with sulphuric acid. Both materials presented high lignin yield recovery in the liquid stream.

Eco-friendly extraction of banana peel cellulose using a wood charcoal ash solution and application of process wastewater as a naturally-derived product

To avoid using a strong alkaline in a dietary fiber extraction process and to reduce residual chemical waste, a natural alkaline solution was tested to extract cellulose fiber from banana peels. A charcoal ash solution could extract fiber from banana peels, and it had a cellulose purity of 74 %, which is comparable to NaOH-treated fiber in terms of its physical and chemical properties. In addition to using fewer chemicals and less complicated techniques, the proposed green technology could extract cellulose at least 10 h faster than the traditional method. Not only dietary fiber was obtained, but the wastewater of this extraction process contained useful phytochemical compounds and it also showed the potential of being a brown fabric dye. Thus, this study reveals a zero-waste concept with green technology by the reuse of agricultural wastes and converting wastewater from the process into value-added products.

Microwave Assisted Synthesis of Antimicrobial Nano-Films from Water Hyacinth <i>(Eichhornia crassipes)</i> and Roselle <i>(Hibiscus sabdariffa</i>) Plant Extract

Cellulose based nanofilms have large applications in biomedical and related fields due to their antimicrobial properties. Their applicability depends upon purity of cellulose, composition, and structural properties of films. The nanofilms of cellulose extracted from Water Hyacinth (Eichhornia crassipes) and Roselle (Hibiscus Sabdariffa) plant possesses excellent properties for biomedical applications due to their biological origin and ZnO or other metal loading properties. Microwave assisted physical separation of cellulose provided excellent films formation properties and ZnO loading compared without any chemical traces. The presence of chemical impurities to affects structural, morphological properties and contact angle. It affects the biomedical applicability of cellulose based films. The microwave-based extraction was further assisted by use of polyethylene glycol with molecular weight 600, which increases the solubility and extractability of cellulose to 90 %. Formed films showed higher contact angle and hydrophobicity. This increased hydrophobicity of cellulosic nanofilms showed enhanced antimicrobial activities towards gram-negative and gram-positive bacteria by water hyacinth nanofilms. Thus, microwave-based synthesis of cellulose nanofilms resulted into enhanced microbial activities.

Isolation of microcrystalline alpha-cellulose from jute: A suitable and economical viable resource

Cellulose is a natural linear chain homopolymer that is an abundant and common component in all plants. Partially pure depolymerized cellulose, known as microcrystalline cellulose (MCC), is synthesized by mineral acids hydrolysis from α-cellulose precursors obtained from fibrous plants such as jute. Virgin soft and hardwoods are used as the main source of cellulose for raw materials of MCC production. These can be replaced by jute fiber to a great extent as it is considered one of the most promising alternatives. A proximate analysis had been carried out to determine the percentage of cellulose, hemicellulose, fats, and lignin in cellulose by standard methods. The cellulose purity of BJRI Tossa Pat-8 (Robi-1) fiber is identified from FT-IR. The IR results of MCC analysis were indicated 3,337.40cm-1 for the moisture and 1656.45cm-1 for carboxyl groups. In thermogravimetry analysis, at the first phase, 20-95oC is associated with moisture release. The oxidation of Tossa Pat-8 (Robi-1) MCC occurred in the range of 200-400oC. The remaining 0.65% of inorganic materials ash, was obtained at 425oC. This study indicates the cost-effective isolation of MCC from Tossa Pat-8 (Robi-1) and that can be promisingly applicable in several fields such as coatings and membranes explosives, cellulose, textiles, adhesives, films, textiles, food and tobacco, films, pharmaceutical and cosmetics industry, which needs further research.

Extraction of the wheat straw hemicellulose fraction assisted by commercial endo-xylanases. Role of the accessory enzyme activities

Wheat straw is a highly promising raw material for bio-refinery strategies. Most of the literature related to lignocellulose fractionation focuses on cellulose purification and hemicellulose solubilization. Pre-treatments for hemicellulose solubilization without the formation of undesired products usually reach low extraction yields, which leaves an important hemicellulose fraction unused. In this work, we propose a mild process for the efficient extraction of the hemicellulose fraction of wheat straw assisted by partial enzymatic hydrolysis with three commercial endo-xylanase cocktails. A first step with alkali at 40 ºC helped to disrupt the lignocellulosic structure and removed 19% of lignin while maintaining most of the hemicellulose in the solid. The enzymatic step enabled reaching extraction yields of 59.8%, 51.9%, and 42.5% with Ultraflo L, Pentopan mono conc, and Shearzyme 500L, respectively. We also discuss the catalytic properties of each endo-xylanase, in particular, their adscription to the GH10 or GH11 glycosyl hydrolase family, and the relevant role of accessory enzymes.

Preparing prehydrolyzed kraft dissolving pulp via phosphotungstic acid prehydrolysis from grape branches

Dissolving pulp was successfully prepared via phosphotungstic acid (PTA) prehydrolysis kraft (PHK) cooking followed by an elemental chlorine-free (ECF) bleaching process from grape branches. The effects of prehydrolysis temperature, reaction time, and PTA concentration that potentially affect the quality of dissolving pulp product on chemical components of pulp were studied via an orthogonal experiment. The structure of lignin was activated during the PTA prehydrolysis phase, and lignin was easily removed during the following cooking process. Thus, relatively mild conditions (140°C, 100 min) can be used in the cooking process. During the prehydrolysis phase, temperature exhibited the most significant influence on the cellulose purity of the obtained pulp fiber, followed by reaction time and PTA concentration. The optimized prehydrolysis conditions were as follows: prehydrolysis temperature, 145°C; reaction time, 75 min; and PTA concentration, 1 wt%. Whether the excessively high prehydrolysis temperature or prolonging the reaction time did not favor the retention of long chain cellulose, the delignification selectivity for the cooking process could not be further improved by excessive PTA loading. Under these prehydrolysis conditions, 94.1% and 29.0% for α-cellulose content and total yield could be achieved after the given cooking and bleaching conditions, respectively. Moreover, the chemical structure and crystal form of cellulose were scarcely changed after PTA prehydrolysis, which could be confirmed by results from Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD). PTA prehydrolysis could be considered as an alternative method for preparing PHK dissolving pulp under relatively mild cooking conditions.

High-pressure autohydrolysis process of wheat straw for cellulose recovery and subsequent use in PBAT composites preparation

The effect of autohydrolysis (AH) temperature (165 °C, 195 °C, 225 °C) on the structure, purity, and recovery yield of the cellulose residue isolated after additional alkaline and bleaching steps from wheat straw, was investigated. The processes were quantified for mass yields in the different steps and for antioxidants and sugars release during AH. AH at 195 °C allowed for the highest cellulose residue yield (83.5%) with purity (∼70%) and structure similar to the other residues. FTIR and XRD analyses showed straw cellulose (SC) with a type II polymorphism and crystallinity index increasing with AH temperature. SC obtained at the end of the entire fractionation process (SC-195 °C) starting from AH residue-195 °C was tested as a reinforcing agent in different percentage (0, 2 and 5% by weight) in poly(butylene adipate- co -terephthalate) (PBAT) films. The Young's modulus of the films increased by ∼17% with 5 wt% cellulose, while tensile strength and elongation at break decreased. • Investigation of autohydrolysis pretreatment for cellulose recovery from wheat straw • Effect of autohydrolysis on cellulose purity and structure • Cellulose from autohydrolysis tested as a reinforcing agent for PBAT films • Improvement of Young's module of PBAT films with cellulose

Production of Cellulose From Bamboo Shoot Shell Using Hydrothermal Technique

The preparation and characterization of purified cellulose from bamboo shoot shell were studied using fouriertransform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The preparation of cellulose fiber included extraction of cellulose from bamboo shoot shell by treatment with 5 % NaOH and 4 % H2O2, and purification of cellulose fiber using hydrothermal technique. The result showed that cellulose has been successfully extracted at a 32.56% yield by the 5% NaOH / 4% H2O2 treatment, and the purified cellulose was produced using autoclaving at the temperature of 120 °C and pressure at 0.1 MPa for 2 h 5 min, with the % recovery of purified cellulose around 94.08. Bamboo shoot shell and cellulose sample were further characterized using FTIR technique. It was found that the 5% NaOH / 4% H2O2 treatment eliminated lignin and hemicellulose from bamboo shoot shell but did not affect cellulose. The hydrothermal technique did not affect the destruction of the cellulose structure as well. Comparison of the SEM image showed that cellulose was separated into individual microfibers after the 5% NaOH / 4% H2O2 treatment while the SEM image of purified cellulose was the small thread-like fibers with smoother surface. Therefore, hydrothermal treatment can be performed for purification of cellulose.

Characterization of Birch Wood Residue after 2-Furaldehyde Obtaining, for Further Integration in Biorefinery Processing.

Latvia is a large manufacturer of plywood in Eastern Europe, with an annual production of 250,000 m3. In Latvia’s climatic conditions, birch (Betula pendula) is the main tree species that is mainly used for plywood production. A significant part of the processed wood makes up residues like veneer shorts, cores, and cut-offs (up to 30%), which have a high potential for value-added products. The aim of this research was to comprehensively characterize lignocellulosic (LC) biomass that was obtained after 2-furaldehyde production in terms of further valorization of this resource. The polymeric cellulose-enriched material can be used in the new biorefinery concept for the production of 2-furaldehyde, acetic acid, cellulose pulp, thermomechanical (TMP) and an alkaline peroxide mechanical (APMP) pulping process. In addition, we experimentally developed the best 2-furaldehyde production conditions to optimize the purity and usability of cellulose in the leftovers of the LC material. The best experimental results in terms of both 2-furaldehyde yield and the purity of residual lignocellulose were obtained if the catalyst concentration was 70%, the catalyst amount was 4 wt.%, the reaction temperature was 175 °C,and the treatment time was 60 min. After process optimization with DesignExpert11, we concluded that the best conditions for maximal glucose content (as cellulose fibers) was a catalyst concentration of 85%, a catalyst amount of 5 wt.%, a temperature of 164 °C, and a treatment time of 52 min.

Valorization of alginate-extracted seaweed biomass for the development of cellulose-based packaging films

Seaweed residues from Alaria esculenta, Saccharina latissima and Ascophyllum nodosum after alginate extraction have been valorized to produce cellulose-based fractions with different purification degrees. The residues were mainly composed of carbohydrates (35–57%) and proteins (12–37%), Alaria and Saccharina being richer in cellulose and Ascophyllum richer in fucoidan. The lower cellulose content in the latter made it unsuitable for the extraction of cellulosic fractions.Self-supporting films were obtained from the cellulosic fractions from Saccharina and Alaria residues. While the higher cellulose purity films presented more desirable characteristics in terms of mechanical properties (with elastic moduli of ca. 5–7 GPa and elongation values of ca. 3–5%) and visual appearance, the presence of non-cellulosic components in the films from less purified fractions reduced their water sensitivity and promoted greater water barrier (with water permeability values of ca. 4–6 kg·m/s·m2·Pa). These results point towards the potential of a simple alkaline extraction to generate cellulose-based films from seaweed residuals with the best compromise between functional properties and economical and environmental efficiency.

Separation of Cellulose from Rice Hull

Rice hull was proposed as an alternative raw material for cellulose production. Rice hull has cellulose (38.6+/-0.1%), xylan (12.8+/-0.1%), lignin (22.7+/-0.7%), extractives (7.9+/-0.4%), and inorganic (13.2+/-0.8%).Inorganic was selectively removed using moderate alkaline extraction, and lignin was degraded via oxidation with chlorine dioxide or hypochlorite. In this study, dilute acid hydrolysis was used to selectively remove hemicellulose, resulting in purer cellulose and better yield. Xylan was selectively removed using sulfuric acid at various acid concentrations (0.25–1 N), reaction time (60–120 min), and temperature (100–120°C) with desilicated and delignified biomass. The reaction conditions for ＞90% cellulose purity were 120°C and 1.0 N sulfuric acids. Increasing the reaction duration resulted in higher cellulose purity, with the greatest purity being 96.1% at 1.00 N sulfuric acid, 120°C, and 120-min reaction time.

Dilute Acid Hydrolysis of Jute Bast Fiber for Selected Xylan Removal

Jute fiber was proposed as an alternative raw material for dissolving pulp production. Jute fiber had cellulose (71.8%±0.1%), xylan (10.8%±0.1%), lignin (13.7%±0.2%), and extractives (3.8%±0.0%). In this study, jute fiber was hydrolyzed with H₂SO₄ to remove xylan. To achieve the best conditions for removing hemicellulose and obtaining a high cellulose content, acid hydrolysis pretreatment was performed at various acid concentrations (0.25-1 N), reaction times (60-120 min), and temperatures (100°C-120°C). The results showed that the optimum condition of acid hydrolysis for higher dissolving pulp raw material yield within less than 5.0% xylan was cellulose (60.5±0.2) and xylan (2.9±0.2) at 1 N H₂SO₄, 100°C for 90 min. However, by increasing the reaction temperature to 120°C for 120 min, the chemical used was reduced to 0.25 N H₂SO₄ and the highest purity of cellulose was produced, with cellulose and xylan content of 56.1%±0.1% and 1.3%±0.1%, respectively.

Effects of Different Extraction Solvents on the Extractive Removal and Properties of Oil Palm Empty-Fruit Bunch Cellulosic Nanofibers

In this study, the effect of different extraction solvents on the isolation and properties of cellulosic nanofibers (CNFs) were investigated. The unextracted and different solvent-extracted CNFs formed horn-like features and irregularly aggregated nanofibers after oven drying. Scanning electron microscopy at 10000× magnification revealed the smooth external surfaces of all extracted CNFs; this finding is attributed to the limited deposition of amorphous lignocellulosic components on the fibers. All resultant CNF solutions revealed aggregation, with a particle size distribution and zeta average of 21.39–513.00 nm and 162.26–342.13 nm, respectively. Extraction with different solvents and chemical treatment yielded CNF solutions with good transparency. Increases in crystallinity indices were generated by extractive removal and enhanced the delignification and bleaching processes. The atomic crystal size of untreated and different solvent-treated CNFs varied with the type of native cellulose. A dramatic decrease in organic (i.e., C, N, and O) and inorganic (i.e., Na, K, and Si) elements was observed following extractive removal and cellulose purification

Enzymatic Fibre Modification During Production of Dissolving Wood Pulp for Regenerated Cellulosic Materials.

The production of regenerated cellulosic fibres, such as viscose, modal and lyocell, is based mainly on the use of dissolving wood pulp as raw material. Enzymatic processes are an excellent alternative to conventional chemical routes in the production of dissolving pulp, in terms of energy efficiency, reagent consumption and pulp yield. The two main characteristics of a dissolving pulp are the cellulose purity and the molecular weight, both of which can be controlled with the aid of enzymes. A purification process for paper-grade kraft pulp has been proposed, based on the use of xylanases in combination with hot and cold caustic extraction, without the conventional pre-hydrolysis step before kraft pulping. This enzyme aided purification allowed the production of a dissolving pulp that met the specifications for the manufacture of viscose, < 3% xylan, > 92% ISO brightness and 70% Fock’s reactivity. Endoglucanases (EGs) can efficiently reduce the average molecular weight of the cellulose while simultaneously increasing the pulp reactivity for viscose production. It is shown in this study that lytic polysaccharide monooxygenases act synergistically with EGs in the modification of bleached dissolving pulp.