Α-cellulose Content Research Articles

Upcycling industrial peach waste to produce dissolving pulp.

This study investigates the production of high-purity cellulose pulp from peach (Prunus persica) fruit wastes generated during the processing of a Greek compote and juice production industry. A three-step chemical process is used, including alkaline treatment with NaOH, organic acid (acetic and formic) treatment, and hydrogen peroxide treatment, with the goal of cellulose extraction and purification. A fractional factorial design optimized reagent levels, revealing the strong influence of NaOH concentration on α-cellulose content and degree of polymerization. The extraction yield ranged between 9.7 and 12.3%, and a yield of 11.6% was achieved under the optimal conditions (NaOH, 3%w/v; acid-to-solid ratio, 6l/kg; H2O2, 0.5% v/v) of the factorial experiment. The resulting samples were further characterized by XRD, FTIR, SEM, and TGA techniques. The results of the XRD and FTIR spectra confirmed the presence of cellulose, with a crystallinity index of approximately 57%, balancing strength and reactivity. The SEM analysis demonstrated a strong morphological similarity between the extracted pulp and commercial dissolving-grade pulp (Södra Purple), while images of the raw material confirmed effective purification. Additional evaluations included color, lightness, and lignin content. These findings suggest that cellulose extracted from peach waste is suitable for textile applications, offering a sustainable alternative to conventional cellulose sources and supporting industrial resource efficiency.

Role of lignin removal on the properties of crude pulp fibers from corn stover via high-temperature formic acid pulping.

An effective removal of lignin could reduce the chromogenic groups of lignin in pulp. Herein, corn stover was pulped via the formic acid to investigate the effects of cooking time and temperature on the crude pulp properties. The strong hydrogen ion action of formic acid helped inhibiting both the re-polymerization of degraded lignin molecules and the subsequent adsorption on fiber. The brightness of the crude pulp could reach 51.5%ISO with the increased lightness and decreased yellowness. The effective lignin removal reduced the residual lignocellulosic bundles in the crude pulp with the increased cooking temperature and time. The lowest lignin content of 3.5%, α-cellulose content of 94.0%, and Kappa number of 9.3 were obtained. Meanwhile, the lignin and monosaccharide content in the black liquor could reach 13.3% and 28.5%, respectively. The number-average molecular weight of lignin was as low as 818g/mol. These were helpful to form the hydrogen bonds between fibers, thus enhancing the tensile and burst index of paper sheets. The tensile, burst and tearing indices of the corresponding crude pulp were 47.5N·m/g, 1.42kPa·m2/g and 6.53 mN·m2/g, respectively. This work provided valuable practical significance for studying the performance of straw pulp by high temperature formic acid cooking.

Valorization of hazelnut branch pruning wastes to medicinal mushroom (Reishi-Ganoderma lucidum) cultivation and nutritional quality properties

In this study, Ganoderma lucidum ((Fr.) Karst (Reishi) mushroom was cultivated from hazelnut branches (HB). Hazelnut branch pruning waste was used for the first time in Reishi mushroom cultivation. In the study, mushrooms were cultivated by preparing composts from branch pruning wastes by 100%. Yield, biological activity, mushroom quality characteristics, spawn run time and total harvesting time were determined from harvested mushroom fruiting body. In addition, degradation properties of HB due to G. lucidum before and after the mushroom cultivation, chemical analysis of hazelnut branch waste (holocellulose, α-cellulose, lignin, extractives, ash contents and pH) were carried out. The changes occurred in the structure of hazelnut branch according to their initial amounts were examined. According to findings obtained from the current study, 57.11 g/kg yield and 10.72% biological efficiency (BE) was achieved. Mean spawn run time (12.33 days), mean earliness (48.1 days) and mean total harvest time (95.1 days) were recorded. K element was the richest in mushroom fruiting body and HB. Nutritional quality properties were found similar with literature. After cultivation, holocellulose and pH values decreased while lignin, extractive and ash contents proportionately increased but α-cellulose content was not changed significantly in the study. This study showed that HB wastes can be used successfully for the cultivation of G. lucidum.

COBRA-LIKE4 modulates cellulose synthase velocity and facilitates cellulose deposition in the secondary cell wall.

Cellulose is a critical component of secondary cell walls (CWs) and woody tissues of plants. Cellulose synthase (CESA) complexes (CSCs) produce cellulose as they move within the plasma membrane, extruding glucan chains into the CW that coalesce and often crystallize into cellulose fibrils. Here we examine COBRA-LIKE4 (COBL4), a GPI-anchored protein on the outer leaflet of the plasma membrane that is required for normal cellulose deposition in secondary CWs. Characterization of the Arabidopsis (Arabidopsis thaliana) cobl4 mutant alleles called irregular xylem6, irx6-2 and irx6-3, showed reduced α-cellulose content and lower crystallinity, supporting a role for COBL4 in maintaining cellulose quantity and quality. In live-cell imaging, mNeon Green-tagged CESA7 moved in the plasma membrane at higher speeds in the irx6-2 background compared to wild-type. To test conservation of COBL4 function between herbaceous and woody plants, poplar (Populus trichocarpa) COBL4 homologs PtCOBL4a and PtCOBL4b were transformed into, and rescued, the Arabidopsis irx6 mutants. Using the Arabidopsis secondary CW-inducible VND7-GR system to study poplar COBL4 dynamics, YFP-tagged PtCOBL4a localized to the plasma membrane in regions of high cellulose deposition in secondary CW bands. As predicted for a lipid-linked protein, COBL4 was more mobile in the plane of the plasma membrane than CESA7 or a control plasma membrane marker. Following programmed cell death, COBL4 anchored to the secondary CW bands. These data support a role for COBL4 as a modulator of cellulose organization in the secondary CW, influencing cellulose production, and CSC velocity at the plasma membrane.

Lignocellulosic characterisation of Pinus patula wood from Oaxaca, Mexico

Wood is mainly composed of carbohydrates, lignin, and smaller proportions of extractives and minerals. The products that can be obtained and derived from wood depend directly on its chemical composition. This work aimed to determine the contents of α-cellulose, holocellulose, hemicellulose, lignin, and the extractives in ethanol-benzene and ethanol of the wood of six Pinus patula trees. An analysis of variance was performed on the obtained data, followed by a multiple comparison of means (LSD, α = 0.05). The results indicated significant differences (p ≤ 0.05) in the chemical compounds among the six trees. On average, P. patula wood contained 67.93% holocellulose, 43.28% α-cellulose, 24.65% hemicellulose, 28.08% lignin, 2.30% ethanol-benzene extractives, 0.32% ethanol extractives, and 2.62% total extractives.

Sustainable extraction of cellulose nanocrystals from empty palm oil bunches via low-acid hydrolysis

The increasing production of empty palm oil bunches (EPOB) poses significant environmental challenges due to waste accumulation. This study aims to convert EPOB into valuable cellulose nanocrystals (CNCs) through a sustainable extraction process utilizing low-acid concentration. The extraction method involves three key steps: alkalization, bleaching, and hydrolysis with 30 % sulfuric acid. The results indicate a high α-cellulose content of 87.04 % and an increase in crystallinity of the extracted CNCs to 60.28 %, as confirmed by X-ray diffraction analysis. The CNCs exhibit a rod-like morphology with an average diameter of 1.66 nm and a length of 9.85 nm. This research demonstrates that EPOB can be effectively transformed into high-quality CNCs, providing a cost-effective and environmentally friendly alternative for utilizing agricultural waste. The findings support the potential application of CNCs in various fields, including biodegradable materials and coatings, contributing to sustainability in the palm oil industry.

THE EFFECTS OF NaClO2 AND H2O2 AS BLEACHING AGENTS IN THE SYNTHESIS OF CELLULOSE ACETATE FROM OIL PALM EMPTY FRUIT BUNCH

Indonesia is one of the largest palm oil-producing countries in the world. The results of palm oil processing produce a lot of waste, such as oil palm empty fruit bunches (OPEFB). The utilization of OPEFB in Indonesia is minimal, so it needs further development. OPEFB has a very high α-cellulose content, so that it can be used as raw material for manufacturing cellulose acetate. Making cellulose acetate from OPEFB consists of three main steps: delignification, bleaching, and acetylation. This study aims to compare the effects of the concentration of NaClO2 or H2O2 in the bleaching process on the physical properties of cellulose acetate from OPEFB. In the delignification process, 100 mesh-sized OPEFB powder is reacted with 5% sodium hydroxide (NaOH) at 100oC for 2 hours. The residue from deliglinfication was washed using distilled water until pH 7, filtered using filter paper, and dried using an oven at 50oC. The next step is the bleaching process using NaClO2 or H2O2 with concentration variations (1%, 2%, 3%, 4% and 5%). The bleaching process was carried out at 90oC for 1.5 hours. After filtration, the bleached residue was washed using distilled water until pH 7, filtered using filter paper, and dried using an oven at 50oC. After the bleaching process, α-cellulose powder was produced. The next step is acetylation, containing three main steps. The first step is the reaction between α-cellulose powder with acetic acid (CH3COOH) and sulfuric acid (H2SO4) at 40oC for 1.5 hours to perform activation. The second step is the addition of anhydrous cellulose in a ratio of 1:10 and mixed at 40oC for 1.5 hours. The third step is the addition of distilled water, acetic acid, and sodium acetate (CH3COONa) at 40oC for 5 minutes. Then, followed by filtration, the residue was washed using distilled water and methanol until pH 7 and dried at 50oC. The best result is using NaClO2 as a bleaching agent with a concentration of 2%, resulting in cellulose acetate yielding 98.85%, density of 1.954 g/mL, and L value of 91.897 for colorimetric test results. The density and L-value were close to commercial cellulose acetate (Sigma Aldrich). From the results of FTIR analysis, it can be concluded that the acetylation of α-cellulose into cellulose acetate has been successful, as evidenced by the formation of carbonyl groups (C=O).

Effect of pre-hydrolysis on the dissolution of hardwood pulp in double salt ionic liquid

Abstract Ionic liquids (ILs) are potentially alternative solvents for cellulose dissolution. In this article, effect of hemicellulose in cellulose dissolution in ILs and the regeneration process were investigated. Hardwood pulps were produced by kraft (KP) and pre-hydrolysis kraft (PHKP) processes. The α-cellulose and residual pentosan contents were 95.6 % and 4.2 % in PHKP and 84.3 % and 9.9 % in KP, respectively. Both pulps were dissolved in 1-butyl-3-methylimidazolium chloride [C4mim]Cl, 1-butyl-3-methylimidazolium acetate [C4mim]CH3CO2 and their double salt (DSIL), [C4mim](CH3CO2)0.6Cl0.4 at 90 °C. It was observed that PHKP had slightly higher solubility in both ILs and DSIL. The dissolved pulps were regenerated by water and characterized by FTIR, TGA, X-ray diffraction, and viscosity. Regenerated pulp film formed smooth and homogenous surface. The viscosity of regenerated PHKP was higher than the original PHKP, which affected the strength of the produced cellulose film. As observed in FTIR, the regenerated cellulose showed a stronger absorption band at 1,647 cm−1 corresponding to the C–O stretching vibration of C–O–H. The crystalline structures of regenerated KP and PHKP from [C4mim](CH3CO2)0.6Cl0.4 changed to cellulose II form from the original cellulose I form.

Reaction Mechanism in Standardized α-Cellulose Content Test: Study from Boehmeria nivea Fiber

In defense industry, α-cellulose is the main component of nitrocellulose propellant. However, a detailed description of the reaction mechanism of each treatment step in SNI 0444-2009 is still very scarce. This study addresses this gap by presenting the reaction mechanisms of each treatment and the symbols used in the SNI 0444-2009 procedure. The separation of lignin from α-cellulose occurred by breaking the C‒O bond linking them. This bond was broken by the ‒OH group of NaOH via a hydrolysis reaction. The reaction was initiated with the elimination of a hydrogen atom from the lignin structure by the hydroxyl ion (‒OH), and the C‒O bond was broken by a hydrolysis reaction. The breaking of this bond was indicated by the disappearance of the IR peaks at wavenumbers 1049 and 1190 cm–1 in the filtrate after extraction. The SNI 0444-2009 method for the α-cellulose content test was carried out by a redox back titration of Cr(VI) with Fe(II) from ferrous ammonium sulfate. This titration was conducted to calculate the amount of Cr(VI) ions in potassium dichromate or Cr(VI) that did not react with lignin or beta cellulose in the filtrate. Understanding the contribution and reaction mechanisms of each compound involved in the SNI 0444-2009 procedure contributed to obtaining accurate data on α-cellulose content. In this study, the calculated α-cellulose content of the flax fiber was 96.75%. Furthermore, the detailed mechanism of the redox reaction was discussed in detail in this paper.

Upgrading paper-grade bleached hardwood pulp towards dissolving pulp using γ-valerolactone

γ-Valerolactone (GVL) is a promising biomass-based platform compound that can be used for the removal of hemicellulose in pulp. In this study, a paper-grade pulp was treated using GVL to generate dissolving pulp for viscose production. The GVL concentration, treatment temperature, and reaction time had significant effect on the hemicellulose dissolution. The dissolving pulp with α-cellulose content of 92.3% and hemicellulose content of 5.45% was achieved with 60% GVL at 120 °C for 2 h. The Fock reactivity and intrinsic viscosity of the obtained dissolving pulp were 54.6% and 595 mL/g, which is comparable with the commercial product. In addition, GVL spent liquor was also recycled and reused to upgrade paper-grade pulp. By using purified recycled GVL to treat original pulp, the Fock reactivity of pulp was improved, and the cellulose content of as-prepared upgraded pulp increased to 92.1%, which was close to the cellulose content of dissolving pulp obtained from fresh GVL solution, while the intrinsic viscosity decreased significantly to 598 mL/g. Therefore, the efficient reuse of GVL not only ensured the high quality of dissolving pulp, but it also saved production costs and reduced environmental pollution.

Cellulose and lignin purified from Metroxylon sagu palm fronds by a new technology with 2-methylanthraquinone cooking and peroxymonosulfuric acid bleaching

The demand for high-purity cellulose, optimization of wood utilization, and environmentally friendly processes has increased in dissolving pulp (DP) production. Sago palm fronds (SPF), an abundant agricultural waste in Indonesia, hold great potential as a raw material for cellulose, hemicellulose, and lignin production. This study aimed to explore the production of from SPF by employing a combination of prehydrolysis, soda cooking with 2-methylanthraquinone (MAQ) as a green additive (PHS-MAQ), and totally chlorine-free (TCF) bleaching with peroxymonosulfuric acid (Psa). Furthermore, lignin was recovered from the black liquor of PHS-MAQ. The results showed that prehydrolysis at 150 ºC for 3 h, followed by soda-MAQ cooking at 160 ºC for 1.5 h using 0.03% of MAQ, 23% active alkali (AA), and a five-stage bleaching with oxygen (O), Psa, alkaline extraction with hydrogen peroxide (Ep), Psa, and Ep successfully produced high-purity cellulose as DP, with properties of 94.3% α-cellulose content, 89.9% ISO brightness (SNI ISO 2470–1:2016), 9.1 cP viscosity, and 0.13% ash content. Moreover, the soda-MAQ cooking method exhibited superior delignification compared to prehydrolysis kraft (PHK) and prehydrolysis soda (PHS) processes in a range of kappa numbers of 9.4–22.6 at 17–25% AA. The inclusion of MAQ increased pulp yields by 4.6–4.9% and decreased kappa number by 1.6–3.1 compared to the PHS without additives at similar AA. Lignin was separated from the PHS-MAQ, with yields of 69–77%. This work demonstrated the suitability of SPF processed by PHS-MAQ cooking and Psa bleaching for the preparation of viscose rayon and cellulose derivatives. The lignin recovery could be an attractive biorefinery process in modern pulp mills.

Application of frass from black soldier fly larvae treatment of cattle dung in pulp and papermaking

Cattle dung treatments in Taiwan have developed a process called Black soldier fly larvae (BSFL) treatment, which can digest cow dung and generate the frass (larvae drops), the residue fiber in cow dung. This study aims to assess frass for its potential in pulp and papermaking, considering its chemical compositions, appearance, and fiber morphology, and also evaluate its suitability for pulping by soda method to create added value. The frass exhibits favorable material properties for pulping and papermaking, including a high holocellulose (67.37%) and α-cellulose (48.00%) content, along with a lower ash content (4.61%); the microstructure and surface mesoporous pores benefit for pulping; and the nonwood-fiber-like fiber morphology. The pulping experiment shows that 7% NaOH and 75 min of pulping conditions result in proper disintegration of fiber, and the highest accepts ratio (34.06%). The NaOH causes fiber disintegration during pulping, resulting in a higher strength property of the handsheet. The frass pulp blended with TOCC can achieve the ring crush index standards required for cardboard products. In summary, the frass from BSFL treatment of cattle dung can be utilized in pulp and papermaking to enhance circular utilization value.

The effectiveness of alkaline and thermo hydrolysis pretreatments in the bioethanol production from Calliandra calothyrsus wood

The demand in energy is increasing along with the development of technology. However, the utilization of fossil energy as the main current energy sources creates various environmental problems. Hence, it is important to search other energy sources which are environmentally friendly. One of the renewable energy sources is bioethanol produced from woody biomass. The purpose of this study was to investigate the suitability of Calliandra calothyrsus wood under development of alkaline and thermohydrolisis pretreatments. These pretreatments included the variations of 15, 30, 45 and 60 min at 121°C with NaOH concentration of 1, 2, and 3% (w/v). The chemical component analysis was conducted by using the TAPPI method, while the percentage of reducing sugar after saccharification was carried out by the Nelson-Somogy method. The results showed that the highest holocellulose content 60,62%, and the highest α-cellulose content was 64,30%. The highest pulp saccharification test results were obtained from 60 min pretreatment of 3% concentration of NaOH, which was 42,82% and 32,99% wood basis. The highest yield of ethanol potential was obtained from 36 hours saccharification, which was 139 L/Ton. Finally, it is suggested to do additional treatments with variations in concentration and temperature in order to obtain more optimal results.

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%.

CHEMICAL CONTENT AND ANATOMICAL CHARACTERISTICS OF SAGO (Metroxylon sagu Rottb.) FROND FROM SOUTH KALIMANTAN, INDONESIA

This research aims to evaluate the suitability of sago palm waste as a fiber raw material in terms of its chemical content and anatomical characteristics. The chemical content analysis of its extractive components, lignin, holocellulose, α-cellulose, and hemicellulose, was carried out using sago frond powder with a size of 40–60 mesh. Subsequently, functional group analysis was performed using Fourier Transform Infra-Red (FTIR), while anatomical characterization was carried out by calculating the fiber length and diameter, lumen diameter, fiber derivative values, and wall thickness using a microscope connected to a digital camera. Scanning Electron Microscope (SEM) pictures were taken in different magnifications. The results showed that sago frond contains 31.6% α-cellulose and 38% lignin. The α-cellulose content was within the standard range for non-timber forest products, but the lignin content had a relatively high value. Based on the derived value, namely class II, sago frond can be used as pulp and paper raw materials.

Integrated application of morphological, anatomical, biochemical and physico-chemical methods to identify superior, lignocellulosic grass feedstocks for bioenergy purposes

Grasses have sufficient potential to be used in the biofuel industry due to many reasons. Hence, systematic assessments of the lignocellulosic biomass obtained from six grasses namely Arundo donax, Chrysopogon zizanioides, Coix lacryma-jobi, Pennisetum purpureum, Saccharum spontaneum, and Sorghum bicolor have been performed to assess their potential for bioethanol production. Selected morphological (height, internode diameter, number of internodes, fresh biomass, dry biomass, total volatile matter), anatomical (vascular bundle, stain intensity), analytical (crystallinity index of cellulose, thermal stability, hemicellulose, moisture content) and biochemical (α-cellulose, acid insoluble lignin) parameters were investigated and statistically analysed to detect the superior grass species. The study indicates that S. spontaneum harbours promising biofuel potential by having high dry biomass (56.33 g), α-cellulose (55.88–67.76%), but lower thermal stability (Tmax: 344.37 °C). Comparable ligno-cellulose properties with respect to dry biomass (54.60 g), α-cellulose content (45.95–64.14%), Tmax (360.51 °C) have been observed for A. donax. However, relatively higher lignin contents (∼17–23%) and crystalline cellulose (43.63%–46.96%) in S. spontaneum and A. donax might have resulted into lesser saccharification yield (216.04–230.08 mg/g). On that aspect, S. bicolor and C. lacryma-jobi might be useful since they possessed lower lignin (14.03–16.56%) and crystalline cellulose (32.51–33.02%) leading to higher glucose yield (263–420.06 mg/g). Taken together, this study indicates that integration of morphological, biochemical, and analytical properties of biomasses are complex, yet useful to predict a ‘superior donor plant’ for bioenergy purposes.

Axial and radial variation in physical and chemical properties of Borassus flabellifer L. (Palmyra palm)

ABSTRACT A variation study of physical and chemical properties at different radial and axial levels of Borassus flabellifer tree was carried out for the first time. An increasing trend in specific gravity from the centre (NC) towards near the bark (NB) has been observed at all three highest i.e. bottom, middle, and top of the tree. Colour analysis of the wood samples has shown a decreasing order of colour intensity (light to dark) from the NC to the NB positions. Holocellulose, hemicellulose, α-cellulose, and lignin content ranged from 64.19 to 73.42%, 17.5 to 26.85%, 42.22 to 51.02%, and 24.57 to 26.98% respectively. Lignin content was found maximum for the middle of the tree, followed by top and bottom height. Total extractives and ash content were found 1.92%–5.43% and 0.94%–1.69% respectively. This study found that B. flabellifer wood can be potentially utilised for various purposes, such as paper and pulp, and furniture making.

Production of oyster mushroom (Pleurotus ostreatus) from some waste lignocellulosic materials and FTIR characterization of structural changes

In this study, oyster (Pleurotus ostreatus) mushroom was cultivated from hazelnut branches (HB) (Corylus avellana L.), hazelnut husk (HH), wheat straw (WS), rice husk (RH) and spent coffee grounds (CG). Hazelnut branch waste was used for the first time in oyster mushroom cultivation. In the study, mushrooms were grown by preparing composts from 100 to 50% mixtures of each waste type. Yield, biological activity, spawn run time, total harvesting time and mushroom quality characteristics were determined from harvested mushroom caps. In addition, chemical analysis of lignocellulosic materials (extractive contents, holocellulose, α-cellulose, lignin and ash contents) were carried out as a result of mushroom production and their changes according to their initial amounts were examined. In addition, the changes in the structure of waste lignocellulosic materials were characterized by FTIR analysis. As a result of the study, 172 g/kg yield was found in wheat straw used as a control sample, while it was found as 255 g/kg in hazelnut branch pruning waste. The highest spawn run time (45 days) was determined in the compost prepared from the mixture of hazelnut husk and spent coffee ground wastes. This study showed that HB wastes can be used for the cultivation of oyster mushroom (P. ostreatus). After mushroom cultivation processes, holocelulose and α-cellulose content rates decreased while ash contents increased. FTIR spectroscopy indicated that significant changes occurred in the wavelengths regarding cellulose, hemicellulose and lignin components. Most significant changes occurred in 1735, 1625, 1510, 1322 and 1230 wavelengths.

Preparation of Pectin Lyase by fermentation for customized extraction of paper pulp, viscose fiber, and nanofibrillated cellulose from hemp stalks

The environmental and efficiently extracted cellulose technology with a high α-cellulose content from agricultural waste hemp stalks were treated by prepared Pectin Lyase (PL) and trace chemical additives. This extraction technique can obtain different α-cellulose content to meet the conditions for preparing pulp (PPs), viscose fibers (VFs) and nanofibrillated cellulose (CNFs). Specifically, fermentation process of PL (temperature, time, rotation rate and centrifugation rate) was evaluated on the reductive sugar concentration, fungus concentration and activity of hydrolase and lyase. Additionally, the morphological structure, chemical structure, crystallization structure, intermolecular action, and technical indicators of PPs, VFs and CNFs were characterized. The optimal results of fermenting PL were 10.3 U/mL of lyase activity and 36.1 U/mL of hydrolase activity. The technical indicators of PPs were 14.30 N·m/g of the horizontal ring pressure and 64 of the horizontal fold resistance times; The technical indicators of VFs were 2.13 cN/dtex of the intensity and 19.36% of the elongation at break; The length and width of CNFs were 326 nm and 3 nm, respectively.

Co-pulping of Trewia nudiflora and Trema orientalis

Trewia nudiflora, a fast-growing species, was evaluated as a pulpwood. The α-cellulose content of this species was 40.4% with a Klason lignin of 21.5%. It was characterized by shorter fibers with a thin cell wall. The pulp yield was 40% with a kappa number of 16 at the conditions of 18% active alkali charge and 30% sulfidity for 2 h cooking at 170°C. T. nudiflora was similar to Trema orientalis in anatomical, morphological, and chemical composition; therefore, mixed chips at a 50:50 mixture ratio were cooked under optimum conditions. The pulp yield of mixed chip cooking was 45.4% with a kappa number of 19.4. The tensile and tear index of T. nudiflora pulps were 64.8 N•m/g and 11.5 kPa•m2/g at 35 °SR, respectively. The mixed chips, T. nudiflora, and T. orientalis pulps showed above 81% brightness when bleached by D0(EP)D1 sequence using 20 kg chlorine dioxide (ClO2)/ton of pulp.