Papermaking Potential Research Articles

Anatomy based papermaking potential of some woody plants under different ecological conditions

The increasing use of wood in the forest industry and reduction of forest resources have prompted the paper industry to look for new materials. To this end, this study examined the biometric coefficients of the seven woody stems grown in different regions and investigated suitability for papermaking as an alternative to the use of wood. Wood samples of each species were collected from two different regions in Türkiye: the Kozan region, which has a Mediterranean climate, and the Yuvacık region, which has a mostly oceanic climate. The species included in the study were Phillyrea latifolia (mock privet), Arbutus andrachne (greek strawberry tree), Erica arborea (tree heath), Spartium junceum (spanish broom), Laurus nobilis (bay tree), Pistacia turpentine (cyprus turpentine tree), and Rhus coriaria (elm-leaved sumac). All fibers were classified as short. The longest fiber was observed for Spartium junceum (spanish broom) in Kozan. The fiber diameter was highest for Arbutus andrachne (greek strawberry tree) from Kozan, followed by Rhus coriaria (elm-leaved sumac) from Yuvacık and Laurus nobilis (bay tree) from Kozan. The fiber dimensions and the relationship between them were statistically analyzed. These included the slenderness ratio, flexibility coefficient, Runkel ratio, rigidity coefficient, Luce’s shape factor, F-factor, and Muhlsteph ratio. Although differences in fiber properties were detected between the two regions, it was determined that these were not enough to affect the desired properties for paper production. It was concluded that the fibers could be used in pulp, paperboard, and corrugated board production when mixed with long fibers.

Evaluation of pulp and paper-making potential of Acacia melanoxylon based on chemical composition grown at Chencha, Ethiopia

The study aimed to examine the chemical composition of Acacia melanoxylon wood as a potential raw material for pulp and paper manufacturing. Samples of Acacia melanoxylon were taken systematically based on tree height at the bottom (10%), middle (50%), and top (90%) of market height. The sample was sorted, dried, milled, and sieved, and all chemical compositions were determined by the standards outlined in ASTM except cellulose and hemicellulose, which were determined by the Kurschner-Hoffer and alkali extraction methods, respectively. The results of the study showed that the overall average values of chemical composition along tree height levels were 45.02%, 21.94%, 23.79%, 5.52%, 3.24% and 0.48% for cellulose, hemicellulose, Klason lignin, hot-water solubility, alcohol-benzene extracts, and ash content, respectively. Except for hot-water extractives, the chemical composition of the bottom and top portions differed significantly. Generally, this study suggests that the chemical composition of Acacia melanoxylon wood is well suited for pulp and paper production.

Структурно-морфологические свойства вторичного волокна из влагопрочного сырья при мягком размоле. Часть 1. Характеристика волокон

The efficient use of papermaking potential of secondary fiber by gentle refining of recycled pulp is one of the basic principles for the recovered paper stock preparation. The use of mild refining modes for recycled fiber is more important in the case of wetstrength paper than for conventional waste paper. This is due to the fact that recycled fiber is weakened by hard conditions of wet-strength paper repulping, in particular, long repulping time, elevated temperature, the use of alkali and oxidizers. The study aims at evaluating the changes in the morphological characteristics of secondary fiber during gentle low-consistency refining of recycled pulp. The analysis of the secondary fiber morphological characteristics was carried out in two complementary directions, i.e. the analysis of the fibers (part 1) and the analysis of the fines (part 2). Recycled pulp (RP) was obtained from commercial wetstrength tissue paper consisting of 100 % bleached softwood kraft pulp (BSKP) made of pine (Pίnus sylvéstris L.). The wet-strength paper repulping was performed at 60 °C in three ways, namely, repulping with sodium hydroxide (indicated as RP(NaOH)), repulping with sodium hydroxide and sodium persulfate (RP(NaOH + Na2S2O8)), and finally repulping with sodium hydroxide and potassium monopersulfate (RP(NaOH + KHSO5)). Secondary fibers as well as primary fibers of BSKP had similar length distribution before and after gentle refining. Mean fiber length after first recycle reduced by 5–6 %. The calculated values of the fibershortening index showed that fiber cutting practically does not occur during gentle refiningof the recycled pulps. The increase in the refining degree of the pulps is mainly explained by the fibrillation of secondary fibers, rather than the formation of a large amount of fines. Secondary fibers obtained from the wet-strength paper have a high slenderness ratio ((L/W)l from 66.3 to 66.5 and (L/W)w from 83.6 to 84.3; where L – length, W – width) corresponding to pulp with good papermaking potential. The results showed that low-consistency gentle refining of the recycled pulp obtained by accelerated persulfate and monopersulfate repulping of the wet-strength paper leads to fiber straightening. The overall increase in the shape factor of secondary fibers was achieved due to a combination of accelerated repulping of the wetstrength waste paper (by ~ 60 %) and gentle refining of the pulp (by ~ 40 %).

Impact of shredding degree on papermaking potential of recycled waste

The properties of paper products depend on the structure of the cellulose fibres therein. Although fibre properties in virgin pulps can be modified by a refining process, this is more difficult in pulp from recovered fibre, particularly waste from office shredders that tend to shorten fibres during shredding. The shorter fibres in shredded paper make it difficult to easily reconstitute them into high-quality paper products. Moreover, because of high energy usage during the recycling process and transportation inefficiencies, there is a need to determine how to responsibly shred paper to alleviate this environmental burden. With this in mind, the influence of initial fibre length on the tensile properties of paper was investigated. Changes in initial fibre length significantly influenced many pulp and paper properties. It was found that cutting the paper into pieces with an area less than 25 mm2 caused significant changes in the important morphological parameters of the fibres and a sharp decrease in the tensile properties of the reconstituted paper.

WOOD ANATOMICAL STUDIES REVEAL TAXONOMIC RELATIONSHIPS, ENVIRONMENTAL INFLUENCE AND PULP POTENTIAL IN FOUR TAXA OF Mussaenda (RUBIACEAE) GROWN IN NIGERIA

Current study was carried out to assess the taxonomic, ecological significance, and paper making potential of four taxa of Mussaenda L. (Rubiaceae) viz., M. elegans, M. erythrophylla, M. philippica var. aurorae, and M. ‘Dona Aurora’ through wood anatomical studies. Each of the taxa was collected from its natural region of provenance in two different ecological zones (Derived Savanna and Tropical Rainforest) of Nigeria. Observations from different planes of sections were made and wood maceration was carried out for fibre morphology. Absent to scanty paratracheal axial parenchyma, septate fibres, pitted vessels, storied heterocellular rays, and simple perforation plates were common features in all taxa. However, multiseriate and wider rays distinguished the exotic species from the indigenous species, and the semi-diffuse porous wood pattern was a unique feature in M. ‘Dona Aurora’. Quantitative data showed considerable variations in case of fibre lengths among the four taxa i.e. M. elegans, M. erythrophylla, M. philippica var. aurorae, and M. ‘Dona Aurora’ and was recorded 0.80 ± 0.02 µm, 0.70 ± 0.05 µm, 0.65 ± 0.03 µm and 0.64 ± 0.04 µm respectively. These observations showed that all species belong to Wood Type II of Rubiaceae and support their inclusion in the Tribe Mussaendeae and Order Ixoroideae. The influence of environmental factors was evident in the significant elongation of wood vessels of samples collected from more humid areas, but with no significant effect on their paper-making potential. More so, M. “Doña Aurora”, had general scores, would be most suitable for pulp and paper making.

WOOD ANATOMICAL STUDIES REVEAL TAXONOMIC RELATIONSHIPS, ENVIRONMENTAL INFLUENCE AND PULP POTENTIAL IN FOUR TAXA OF Mussaenda (RUBIACEAE) GROWN IN NIGERIA

Current study was carried out to assess the taxonomic, ecological significance, and paper making potential of four taxa of Mussaenda L. (Rubiaceae) viz., M. elegans, M. erythrophylla, M. philippica var. aurorae, and M. ‘Dona Aurora’ through wood anatomical studies. Each of the taxa was collected from its natural region of provenance in two different ecological zones (Derived Savanna and Tropical Rainforest) of Nigeria. Observations from different planes of sections were made and wood maceration was carried out for fibre morphology. Absent to scanty paratracheal axial parenchyma, septate fibres, pitted vessels, storied heterocellular rays, and simple perforation plates were common features in all taxa. However, multiseriate and wider rays distinguished the exotic species from the indigenous species, and the semi-diffuse porous wood pattern was a unique feature in M. ‘Dona Aurora’. Quantitative data showed considerable variations in case of fibre lengths among the four taxa i.e. M. elegans, M. erythrophylla, M. philippica var. aurorae, and M. ‘Dona Aurora’ and was recorded 0.80 ± 0.02 µm, 0.70 ± 0.05 µm, 0.65 ± 0.03 µm and 0.64 ± 0.04 µm respectively. These observations showed that all species belong to Wood Type II of Rubiaceae and support their inclusion in the Tribe Mussaendeae and Order Ixoroideae. The influence of environmental factors was evident in the significant elongation of wood vessels of samples collected from more humid areas, but with no significant effect on their paper-making potential. More so, M. “Doña Aurora”, had general scores, would be most suitable for pulp and paper making.

WOOD ANATOMICAL STUDIES REVEAL TAXONOMIC RELATIONSHIPS, ENVIRONMENTAL INFLUENCE AND PULP POTENTIAL IN FOUR TAXA OF Mussaenda (RUBIACEAE) GROWN IN NIGERIA

Current study was carried out to assess the taxonomic, ecological significance, and paper making potential of four taxa of Mussaenda L. (Rubiaceae) viz., M. elegans, M. erythrophylla, M. philippica var. aurorae, and M. ‘Dona Aurora’ through wood anatomical studies. Each of the taxa was collected from its natural region of provenance in two different ecological zones (Derived Savanna and Tropical Rainforest) of Nigeria. Observations from different planes of sections were made and wood maceration was carried out for fibre morphology. Absent to scanty paratracheal axial parenchyma, septate fibres, pitted vessels, storied heterocellular rays, and simple perforation plates were common features in all taxa. However, multiseriate and wider rays distinguished the exotic species from the indigenous species, and the semi-diffuse porous wood pattern was a unique feature in M. ‘Dona Aurora’. Quantitative data showed considerable variations in case of fibre lengths among the four taxa i.e. M. elegans, M. erythrophylla, M. philippica var. aurorae, and M. ‘Dona Aurora’ and was recorded 0.80 ± 0.02 µm, 0.70 ± 0.05 µm, 0.65 ± 0.03 µm and 0.64 ± 0.04 µm respectively. These observations showed that all species belong to Wood Type II of Rubiaceae and support their inclusion in the Tribe Mussaendeae and Order Ixoroideae. The influence of environmental factors was evident in the significant elongation of wood vessels of samples collected from more humid areas, but with no significant effect on their paper-making potential. More so, M. “Doña Aurora”, had general scores, would be most suitable for pulp and paper making.

Papermaking as Potential Use of Fibers from Mexican Opuntia ficus-indica Waste

The papermaking potential of Opuntia ficus-indica (OFI) waste fibers was studied in this research. Alpha cellulose, lignin, hollocellulose, ethanol/benzene extractives and ash content were determined as 53.7±0.1%, 2.4±0.3%, 61.6±5.7%, 7.1±0.3% and 26.4±0.1%, respectively. The average fiber length, width, lumen and cell wall thickenss were found to be 1.1±0.3 mm, 18.8±6.1µm, 12.1±5.4 µm, 4.3±1.0 µm. Soda pulping was conducted using 20 and 28% sodium hydroxide, cooking temperatures of 160 and 175 °C, cooking times of 60 and 120 min, and liquor- to fiber ratio of 9:1. Soda pulping with 28% sodium hydroxide, 175 °C and 120 min showed a lower Kappa number of 29.60±1.7 and a total yield of 32.2±1.6 %. In general, tensile strength index (36.0±5.0 Nm/g), stretch (1.7±0.3%), breaking length (3.7±0.5 km), burst index (3.2±0.4 KPa.m2/g), tear index (7.3±0.0 mN.m2/g), folding endurance (166 times) and porosity (> 120 s) of OFI pulp were comparable with wood and non-wood pulps.

Assessment of the papermaking potential of processed Miscanthus × giganteus stalks using alkaline pre-treatment and hydrodynamic cavitation for delignification

One way of satisfying increased market demand and simultaneously achieving a reduced environmental load in the industrial paper production is the use of fibrous agricultural residues. The aims of this study were i) to investigate the effect of alkaline – hydrodynamic cavitation (HC) pre-treatments on the delignification of Miscanthus × giganteus stalks (MGS) and ii) establishing the suitability of MGS as feedstock and their exploitation in pulp and paper manufacturing. It was demonstrated that the proposed treatment is an efficient delignification method for the non-wood fiber sources, such as miscanthus. A significant outcome of this work was the observation that HC treatment preserved the fibres lengths and surface quality of raw MGS, but at the same time increased the amount of kinked and curled fibers present in cavitated miscanthus fibers. The average miscanthus fiber length was found to be relatively short at 0.45 (±0.28) mm, while the slenderness ratio, the flexibility coefficient and Runkel ratio values were calculated to be 28.13, 38.16 and 1.62, respectively. The estimated physical properties of MGS pulp hand-sheets were 24.88 (±3.09) N m g−1 as the tensile index, 0.92 (±0.06) kPa m2 g−1 as the burst index and 4.0 (±0.37) mN m2 g−1 as the tear index. Overall the current work demonstrated effective use of hydrodynamic cavitation for improving the processing in pulp and paper manufacturing.

Pulp and Paper Making Characteristics of Fibers from Plantation-grown Oxythenantera Abyssinica and Beema Bamboo (A Tissue Cultured Clone from Bambusa Balcooa)

ABSTRACT The alarming global deforestation rate has great impacts on the output of the Pulp and paper Industry since wood is the principal papermaking fiber material. Although, generally, bamboo is an alternative cellulolytic fiber source, the species and culm age have great effects on its papermaking potential. Based on the methods by the International Association of Wood Anatomists (IAWA), this work assessed the characteristics of fibers from the axial culm sections of six-month plantation-grown Oxythenantera abyssinica and Beema bamboo (which was cloned from Bambusa balcoaa) for paper production. The lengths of the fibers ranged from 1.89 to 2.39 mm while the diameters were 0.025–0.031 mm. The fiber lumen diameter and wall thickness were 0.014–0.018 mm and 0.004–0.006 mm, respectively. Fibers from the species had their runkle ratios below 1, slenderness ratios above 70 and flexibility ratios above 50. These characteristics compare well with the recommendations for fibers often used for the production of packaging, writing and printing papers. Establishment of plantations of Beema bamboo and O. abyssinica is encouraged as they will serve as good raw material base for the paper industry within six months of planting. Additionally, their planting will contribute to meeting Sustainable Development Goals 1 and 13.

Biometry and verification of papermaking potential of secondary xylem fibers of two Theobroma species

Theobroma glandiflorum and T. cacao, known as cupuacu and cacao, respectively, are species widely used for food purposes. However, when plantations are renewed, these plants are discarded, making studies on the reuse of this material necessary. Thus, the objective of this study was to perform biometry of cellular elements and to investigate the papermaking potential of the fibers of these two species. We used the cellular element maceration technique to measure fiber and vessel element dimensions and calculated the fiber slenderness ratio, wall fraction, coefficient of flexibility and the Runkel index. According to the classification literature, the fibers of these species were of medium size, and there was a significant difference in wall thickness, with cupuacu fibers being thicker. The values of the fiber slenderness ratio and the coefficient of flexibility were higher in cocoa, while those of wall fraction and the Runkel index were higher in cupuacu. To conclude, the fibers of both species have papermaking potential. However, the paper manufactured with these fibers should be tested to confirm the results of this study.

Comparative studies of fibres of woody species selected in relation to their paper-making potentials

The wood fibre used by the paper industry originates primarily from forests. Apart from Gmelina arborea, there are other fast-growing plant species whose fibre characteristics are yet unknown. In order to relieve the pressure and demand on G. arborea, this work was aimed at characterizing and comparing the fibres of four tree species (Parkia biglobosa, Arzadirachta indica, Alstonia boonei and Cassia siamea) to G. arborea, with the intention of elucidating their suitability for the pulp and paper industry. The trunk wood samples used in this study were collected from the Botanical Garden of the University of Nigeria, Nsukka, while the study was conducted in the Plant Anatomy Laboratory in the Department of Plant Science and Biotechnology, University of Nigeria, Nsukka, Enugu State-Nigeria. The results showed that the mean fibre length ranged from 1.00 mm in P. biglobosa to 1.70 mm in A. boonei. The fibre lengths of G. arborea and A. booneidid do not vary significantly (P < 0.05). The Runkel ratio ranged from 0.624 to 3.227 across the species with G. arborea and A. boonei recording the lowest values. Conclusively, A. boonei is another pulp wood with good paper-making potential that could substitute the already known G. arborea.

Properties and fibre characterisation of bleached hemp, birch and pine pulps: a comparison

The papermaking potential of bleached kraft pulps made from hemp stalks, hemp woody-core and hemp bast fibres was studied and compared with that of bleached birch pulp and pine kraft pulp. It has been shown that among the pulps from these raw materials, hemp stalk pulp has the most useful properties for papermaking. The disadvantages of hemp woody-core pulp and hemp bast fibre pulp as papermaking intermediates proved to be low tear resistance and low tensile strength, respectively. Results indicate that the main reasons for the low tensile strength of hemp bast fibre pulp are the low susceptibility of their fibres for internal fibrillation and low hemicellulose content. The technology used in this work for the processing of hemp bast fibres into papermaking pulp made it possible to obtain pulp with high α-cellulose content from this fibrous raw material with a high yield in a much simpler way than when such pulps are obtained from wood.

Pulping and Bleaching of Hydro Distillation Waste of Citronella Grass (Cymbopogon winterianus Jowitt) for Papermaking

This investigation is aimed to explore the pulp and papermaking potential of solid residue left after isolation of essential oil from Cymbopogon winterianus Jowitt using hydro distillation, as well as to evaluate the physical strength properties of pulp and paper produced from it. Soda, soda–AQ (soda–anthraquinone) and kraft pulping of oil isolated C. winterianus were optimized and the corresponding optimum unbleached pulp in each process was subjected to environment friendly ECF (elemental chlorine free) bleaching using D1EpD2 (D = chlorine dioxide in acidic medium; Ep = alkaline extraction with addition of hydrogen peroxide; 1 and 2 = first and second time) sequence. Fibre morphological investigation and fibre classification of bleached pulp from every optimized pulping process were also carried out. Hand sheets of bleached pulps were prepared to evaluate the physical strength properties. All the methods were followed as per standard procedures. The proximate chemical composition of oil isolated C. winterianus revealed 62.70% holocellulose, 37.62% alpha-cellulose, 21.10% pentosans and 24.10% lignin. Kraft pulping at 12% NaOH dose and 20% sulphidity produced unbleached pulp with kappa 18.72, yield 43.68%, brightness 21.36% and viscosity 32.6 cp; while bleached pulp with brightness 83.67% and viscosity 16.7 cp. However, hand sheets prepared from soda–AQ pulping exhibited tensile index 31.5 N m/g, tear index 5.02 m Nm2/g and burst index 2.20 kPam2/g which were superior to kraft pulping. Soda pulp demonstrated inferiority in quality to kraft and soda–AQ pulps. No significant differences were observed in fibre morphology of pulps from different processes while fibre classification revealed maximum useful bleached fibres 55.9% from kraft pulping. This research proved that C. winterianus solid residue left after isolation of essential oil could be a substantial source for pulp and papermaking using conventional pulping processes and ECF bleaching sequence at process conditions described in this work.

Pulping and papermaking potential of six mangrove species in Bangladesh

In this paper, physical, morphological and chemical characterizations of the six main mangrove species of Bangladesh [namely Keora (Sonneratia apetala), Gewa (Excoecaria agallocha), Bine (Avicennia alba), Sundari (Heritiera fomes) Pashur (Xylocarpous mekongests) and Kakra (Bruguiera gymnorhiza)] were discussed in order to assess the suitability of pulping raw materials. The wood density of these six mangrove was found to be 0.5–0.6 g cm−3 except Gewa which had 0.39 g cm−3. The fiber length of these species was varied from 0.74 to 1.2 mm that was considered as short fiber. Sundari contributed the longest fibre length (1.2 mm) among these six species. The chemical results revealed that these species contain high percentages of dichloromethane, followed by methanol extractives. Methanol extracts in Pashur, Sundari and Bine was higher than 10 %, which indicates high percentage of tannin material. These species were characterized with high lignin content and low α-cellulose content. The pulping of these six mangrove species was also carried out by kraft process and papermaking properties were also evaluated. Pulp yield was lower and kappa number was higher as compared with other tropical hardwoods. But the physical properties of these species were quite acceptable. Considering pulp yield, kappa number and physical properties, it may be concluded that Keora and Gewa can be used as kraft liner and other packaging grade paper pulp.

Enzymatic treatment applied as a final stage in E. globulus kraft pulp bleaching

AbstractBACKGROUNDBrightness stability of bleached chemical pulps is often associated with the final bleaching stages that should provide the removal of chromogenic species responsible for brightness reversion without compromising the papermaking potential. Aiming at promoting higher brightness stability, a partially bleached Eucalyptus globulus pulp (DED) of c. 88% ISO brightness was involved in a study of a final enzymatic stage (X) alternative to conventional chlorine dioxide (D) and hydrogen peroxide (P) bleaching stages (DEDX vs. DEDD and DEDX vs. DEDP). X stage was also applied before and after the final P or D stages (DEDDX/DEDXD and DEDPX/DEDXP) to produce high brightness pulps (c. 91%).RESULTSX stage with xylanase Pulpzyme HC allowed an increase of c. 1.5% in pulp brightness while decreasing the brightness reversion and a concomitant pulp yield loss of only 0.5%. Significant chemical savings were obtained in the final D (70%) or P (45%) stages to achieve targeted final brightness of c. 91%. DEDXD or DEDXP sequences had advantage over DEDDX and DEDPX, respectively, in terms of brightness stability of fully bleached pulps.CONCLUSIONSXylanase interferes with structures responsible for the brightness reversion. X stage allows production of pulp with extra brightness in sequences with a final P stage. © 2014 Society of Chemical Industry

Use of Hardwoods in an Integrated Biorefinery: Modelling of the Pretreatment Process and Papermaking Potential

Use of Hardwoods in an Integrated Biorefinery: Modelling of the Pretreatment Process and Papermaking Potential

ХАРАКТЕРИСТИКА ГЕОМЕТРИЧЕСКИХ ПАРАМЕТРОВ ВОЛОКОН ЦЕЛЛЮЛОЗНЫХ ПОЛУФАБРИКАТОВ С ИСПОЛЬЗОВАНИЕМ ВЕРОЯТНОСТНЫХ МЕТОДОВ

Advantages of the mathematical description of geometrical fibers parameters of the polydisperse cellulose half-finished product measured on the automatic analyzer FiberTester using probabilistic-statistical methods are shown. With application specially developed and registered in Federal Institute Industrial Property software the possibilities of additional processing of experimental data are shown. Parameters of lognormal distribution for length and width of fibers with parameters m and s x , and exponential distribution for curvature of fibers with parameter l for hardwood and softwood kraft pulp, both bleached and not bleached are calculated. It is established, that changes of average values of fiber length and width and the form-factor, corresponds to change of parameters of distribution m and l for different grades of kraft pulp It is experimentally confirmed, that the interrelation between separate characteristics of cellulose fibers has probabilistic character as strict functional dependences take place only for average values in classes of length, and in a separate class on length such dependences are absent completely. It is offered to use distribution parameters of fibers characteristics for a quantitative estimation papermaking potential of fibrous half-finished products and modeling of paper structure with the adequate fiber probabilistic-statistical characteristic.

Combination of enzymatic, mechanical and ultrasonic treatments for improvement of the properties of secondary pulps

This study evaluated the property recovery capability of handsheets formed from secondary fibers by combining different techniques. To attain that, pulps derived from post-consumer cardboard scrap were subjected to various refining intensities respectively in a PFI mill (0, 400, 800 and 1200revolutions) and ultrasound (0, 10, 20 and 30minutes), followed by enzymatic treatments with enzymes Cellulase, Hemicellulase, Mixture 1 and Mixture 2 (both mixtures composed of cellulase and hemicellulase). The papermaking potential of the pulps was evaluated by means of physical and mechanical tests on the resulting paper after the relevant treatments. It was found that both the combination of PFI mill refining with enzymatic treatments and the combination of ultrasound with enzymatic treatments were effective in improving paper properties. It was also found that interfiber bonding properties such as tensile index and ring crush strength had greater increases, in relation to the initial pulp, in pulps derived from the combined PFI mill refining with enzymatic treatments. As for intrinsic fiber strength properties, such as tear resistance, had greater increases in pulps derived from the combined ultrasound with enzymatic treatments.

Evaluation of the papermaking potential of Ailanthus altissima

In this work, Ailanthus altissima (tree-of-heaven) wood was analyzed for its chemical, morphological and papermaking properties. The A. altissima wood was cooked under kraft conditions using different active alkali charges and then handsheets were produced with the pulps having a kappa number of 16. Based on structural, strength and optical data it was found that the kraft pulp of A. altissima is not suitable to be used alone for the production of printing and writing papers. Notwithstanding, the handsheets exhibit a favorable value of brightness in comparison to those produced from Eucalyptus globulus pulp (with similar kappa number). Therefore, the wood of A. altissima seems to have a good potential to be used as a partial substitute of the main raw material of the Portuguese pulp industry. In fact, the results showed that when beaten E. globulus and A. altissima pulps were mixed (50:50, w/w), the papermaking properties were comparable to those of beaten eucalypt kraft pulps. Therefore, the use of A. altissima wood seems promising for the production of uncoated wood-free papers, which has advantages both from an economical and environmental perspective.