Wood Pulp Research Articles

Analysis of the commercial eucalyptus plantation sector in Uruguay from a macroeconomic perspective

The Uruguayan forest sector has developed based on commercial pine and eucalyptus plantations. This process has been based on the installation of vertically integrated companies, with foreign capital and some local capital, investment funds and medium and small industries. In addition to these groups, there are contractor companies in which several of the activities of the primary sector are outsourced, as well as some of the industry. Investment attraction factors are diverse and related not only to productive conditions, e.g., growth rates, but also to institutional conditions, e.g., macroeconomic stability. With the development of the forest sector, there is currently a preponderance of eucalyptus plantations over pine plantations. This characteristic has implications in terms of the products to be obtained and, therefore, the industries to be developed, and the markets to be accessed. The presentation analyzes the evolution of the participation of the forest sector in Uruguay's macroeconomy, considering its share in the country's exports as well as in international trade, with emphasis on the products obtained from eucalyptus plantations. The scope and limitations of the available data for Uruguay are considered. Finally, the importance of including the value of ecosystem services provided by the forest in the traditional macroeconomic valuation is discussed. Results show that Uruguay has an important participation in non-coniferous wood markets. According to FAO data, in 2022, Uruguay's production ranked 8th among non-coniferous pulpwood producing countries, after Chile, up one place from the previous year. The same year Uruguay ranked 10th in terms of production of bleached wood pulp. Furthermore, it is expected that the wood pulp will increase with the new operations of the third pulp mill. Furthermore, cellulose pulp ranked 3rd among Uruguay's export products in 2022, after beef and soybeans, and 2nd in the previous year. The results of this research are of interest to potential investors in the Uruguayan forest sector as well as to policymakers. Potential investors in the Uruguayan forest sector may find insights into the industry's growth potential. Policymakers can use this information to make informed decisions that support the development and regulation of the sector for the benefit of both the economy and the environment.

Development of comprehensive calibration models for pulp traits by near infrared spectroscopy (NIRS) for pure species and hybrids of Corymbia and Eucalyptus

Corymbia hybrid has emerged as a complimentary pulpwood in India along with Eucalyptus camaldulensis and eucalypt hybrids for enhancing the profitability of the industry and the income of farmers. Near infrared spectroscopy (NIRS) offers a rapid non-destructive method for estimating wood and pulp traits of short rotation trees. Development of NIR calibration models in Corymbia is essential for quick selection and rapid advancement of pulp wood traits. A study was carried out to develop a combined calibration curve for pure E. camaldulensis and Corymbia species and their interspecific hybrids. Wood samples were extracted from four-year-old 300 trees of Corymbia torelliana (CT), C. citriodora (CC), C. variegata (CV) and E. camaldulensis (EC) and their interspecific hybrids from progeny evaluation trials at three different locations in south India. The wood logs and powdered core samples were analyzed for kraft pulp yield (KPY), lignin and S|G ratio by wet chemistry and NIRS method. The KPY values of CC and CV ranged from 44 to 52%, whereas CT, a maternal parent in CT x CC|CV hybrids, had a narrow range of 38-46.5%. However, the interspecific hybrids of CT x CC|CV exhibited a range with higher values from 48.5 to 50.5%, indicating a narrow scope for predicting hybrids from that of parent’s standard calibration curves. The estimated values in pure species of Corymbia for lignin content ranged from 22.7 to 29.2 % and 1.9 to 3.1 for S|G ratio, while in hybrids it was 25.6 to 29.4 for lignin. The correlation coefficients for cross-validation of KPY in CC, CV, CT and their hybrids were 0.8, 0.81, 0.89 and 0.72, respectively, and root mean square errors (RMS) were 0.8, 0.55, 0.73 and 0.31, respectively. When CC and CV samples were pooled to generate a common prediction model, the correlation coefficients were 0.8 for KPY, 0.75 for lignin and 0.83 for S|G ratio, with RMS of 0.68 for both KPY and lignin, and 0.12 for S|G ratio. Corymbia hybrids were evaluated with 99% accuracy using a combined prediction model of pure Corymbia species and hybrids. The method was validated with 80 samples of pure species and hybrids with a RMS of less than 1.0. We also attempted in developing a combined prediction model for different species of Corymbia, Eucalyptus, and their hybrids with minimum prediction errors.

Ether Bond Formation in Waste Biomass–Derived, Value-Added Technical Hardwood Kraft Lignin Using Glycolic Acid

Ether bond formation in technical hardwood kraft lignin (THKL) by crosslinking using glycolic acid was investigated for bio-adhesive applications. Industrial hardwood kraft black liquor was used to extract the THKL utilized by acidification. Chemical and thermal properties of the THKL with and without crosslinking were analyzed by Fourier transform infrared (FTIR) spectroscopy, solid-state 13C cross-polarization/magic angle spinning nuclear magnetic resonance (13C CP/MAS NMR) spectroscopy, X-ray photoelectron spectroscopy (XPS), gel permeation chromatography (GPC), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). FTIR results revealed a new peak corresponding to the ether bond and hemiacetal formation due to crosslinking at 1075 cm-1 and 1324 cm-1. 13C CP/MAS NMR spectra revealed the presence of a higher number of ether bonds due to the reduced aromatic and aliphatic hydroxyl groups in THKL and new bonds formed at 62-64 ppm and 168-191 ppm due to crosslinking. XPS results revealed that new bonds were formed between glycolic acid and THKL, leading to increased atomic oxygen percentage and carbon–oxygen bonds in crosslinked THKL detected by peak intensity changes at 287.7 and 288.8 related to O–C–O and O–C=O. Also, the oxygen content increased from 14.88% to 31.76% due to bond formation. GPC confirmed a higher molecular weight and broader molecular-weight distribution of THKL. DSC and TGA curves of crosslinked THKL revealed exothermic behavior, high thermal stability, and low thermal degradation rate. Owing to a significant amount of kraft black liquor being generated by wood pulp industries and attractive chemical properties of THKL, THKL demonstrates promise as a raw material to produce green, sustainable bio-adhesives via the crosslinking of its different hydroxyl groups using glycolic acid.

Evaluation of kraft pulp, fibre and paper traits of interspecific hybrid Corymbia clones at four years

Two interspecific Corymbia hybrid clones, ITC 2081 & CH440 (Corymbia torelliana × C. citriodora subsp. variegata), were evaluated for growth, pulp, fibre and paper properties at four years in comparison to an E. camaldulensis (Ec) clone. Wood basic density and fibre traits were estimated from increment core samples and logs were chipped for evaluating pulp and paper traits. The Corymbia clones had comparable growth, but wood basic density was 12% higher than the Ec clone. The fibre traits were superior, with 24% larger fibre in the Corymbia hybrid clones, and 2% higher pulp yield (Kappa number 17) than the Ec clone. The Corymbia hybrid clones had comparable unbleached hand sheet brightness of the Ec clone but were superior in parameters like sheet stiffness, thickness, burst and tear factor. While Ec clones have attained the threshold of pulp wood traits improvement, the new Corymbia hybrids have demonstrated potential for improving the profitability of pulp industries in India.

ELECTROCHEMICALLY TREATED LIGNIN IN PHENOLIC RESINS FOR PLYWOOD PANELS

In achieving the European Union's goal of making Europe the first climate-neutral continent by 2050, the scientific community is striving to develop processes and products that are technologically and economically sustainable to replace/substitute fossil-based feedstocks. In this effort, the European project LIBERATE has demonstrated the commercial opportunities of converting low-cost lignin feedstocks into high-value bio sustainable chemicals such as vanillin and mixed phenolic derivatives.Lignin is the largest regenerative source of aromatic organics. In current wood pulping industries, lignin is underutilized and widely considered a side stream primarily exploited for its energy content. A promising approach for the synthesis of biobased fine chemicals is a depolymerisation process for lignin using sodium peroxodicarbonate (PODIC®), an electrochemically produced oxidiser. Within the LIBERATE project, SINTEF has built a pilot scale plant for the electrochemical lignin depolymerisation. The plant provided CHIMAR with the phenol-rich reactor product solution from both kraft and organosolv lignin, which was used as phenol substitutes with up to 50wt% in the formulation of phenol-formaldehyde (PF) resins. These resins have been able to produce successful plywood panels on a laboratory scale. Although their quality is somewhat lower than that of the reference material with traditional PF resin, this work showed that the use of lignin fractions obtained by electrochemical treatment in such an application is possible and promising.

Structure and properties variations of regenerated cellulose fibers induced by metal ion impurity

In the ionic liquids (ILs) method for processing regenerated cellulose fiber (RCF), which is a high-performance ecologically benign product, metal ion impurities (such as Fe3+ and Cu2+) of cellulose might inevitably remain in the recycled ILs and coagulation bath. The presence of metal ions might negatively impact the properties of the manufactured RCFs and obstruct their applications, which are urgent to be made clear. For this research, the solvent for dissolving wood pulp cellulose (WPC) was 1-ethyl-3-methylimidazolium diethyl phosphate ([Emim]DEP) with various metal ion concentrations. The effect of metal ions in IL on the dissolution of cellulose was investigated by Molecular Dynamics simulations. Rheological analysis and degree of polymerization (DP) analysis were adopted to evaluate the influence on fiber spinnability of different spinning solution metal ion concentrations and various dissolving times. Further, the morphology and mechanical performances of the RCFs variation regulation were also thoroughly researched. The findings showed that the presence of metal ions in the spinning solution affected the DP, crystallinity, and orientation factor of RCFs, which will influence their stress more sensitively than the strain. These findings can serve as a practical guide for the commercial manufacture of emerging fiber.

Profiling of historical rag papers by their non-cellulosic polysaccharide composition

Hemicellulose and pectin are noteworthy components of historical European rag papers, and have not been studied in detail so far. Rag papers were made from used textiles, and fiber-based utilities, such as ropes and bags. These had been prepared until the mid-19th century from plant-based fibers. Their polysaccharide composition could relate to their condition and history. This information can be expected to hold importance for the preservation and conservation of historical objects.We investigated a collection of rag papers of different age for their composition of non-cellulosic polysaccharides, and compared the findings with modern rag papers and wood pulps. Furthermore, a non-destructive determination of the hemicellulose and pectin content by near-infrared spectroscopy was developed.Historical rag papers had a lower hemicellulose/pectin content than pulps; the fractions of rhamnose, galactose, and arabinose were higher, while xylose was lower. In modern rag papers, xylose tended to be at the higher end of the range, which suggests a degradation of hemicelluloses/pectin over time or a change in raw materials and manufacturing. Rag papers also showed higher crystallinity than wood pulp papers. These findings provide insights into rag paper characteristics and offer potential classification methods.

Turning Waste into Treasure: The Full Technological Process and Product Performance Characterization of Flushable Wet Wipes Prepared from Corn Stalk.

As a daily consumable, wet wipes are mostly synthetic fibers, which are incinerated or landfilled after use. The nanoplastics generated during this process will lead to environmental pollution. The application of flushable wet wipes, which are dispersible and fully degradable, is of great significance. The main raw material for flushable wipes is wood pulp, which has a long growth cycle and high cost. Corn is widely planted and has a short growth cycle. Currently most corn stalk is treated by incineration, which produces a lot of smoke that pollutes the environment. Therefore, using corn stalk as the raw material for flushable wet wipes, replacing wood pulp, is both cost-effective and environmentally friendly. In this study, aiming at industrial production, we explored the full process of producing flushable wet wipes from corn stalk to pulp board, then to the final wipes. The corn stalk was treated using alkali and a bleaching agent to obtain corn stalk pulp, which was then made into pulp board through the nonwoven wet-laid process. The optimal parameters for the alkali treatment and bleaching were obtained. The properties of the corn stalk pulp board were compared with the commercial wood pulp board. Further, we mixed the corn stalk pulp with Lyocell fiber to prepare wet-laid webs, which were then bonded using a chemical binder poloxamer. Then, the evenness of the web, mechanical properties, absorption, and dispersibility of the flushable wipes were characterized. Results showed that the pulp obtained using the optimal treatment process has a high yield and better whiteness. The properties of the corn stalk pulp board are comparable with the commercial wood pulp board, which can therefore potentially be replaced by the corn stalk board prepared in our study. The prepared flushable wet wipes had good evenness and their water absorption rate was more than 600%. The mechanical strength in dry and wet states achieved 595.94 N/m and 179.00 N/m, respectively. Most importantly, the wet wipes can completely disperse under the standardized testing method. A good balance of dispersibility and wet strength of the wet wipes was achieved.

Morphological characteristics of spray dried cellulose nanofibers produced using various wood pulp feedstocks and their effects on polypropylene composite properties

Bleached Kraft pulp (BKP), unbleached Kraft pulp (UKP), and old corrugated cardboard pulp (OCC) are excellent feedstock sources for producing CNF suspensions manufactured by a mechanical disk refining process. The CNF drying operation should be performed to produce dry powders that can be compounded into thermoplastic matrices, and spray drying is fast, simple, cost-effective, and scalable. Among several spray-drying techniques, the pilot scale-rotary disk atomizer has many advantages, including large capacities, drying efficiency, and less feed blockage. In this study, BKP, UKP, and OCC pulps fibrillated to 90 % and 100 % fines levels were spray-dried using a pilot-scale rotary disk atomizer. The high-quality micrometer scale, round-shaped powders were produced from all feedstock sources, and a smaller particle size powder was produced with the higher fibrillated pulps. The spray-dried cellulose nanofibrils (SDCNFs) were compounded into a polypropylene (PP) matrix as a reinforcing material, and maleic anhydride-grafted polypropylene (MAPP) was used as a coupling agent. A masterbatch was used for the optimal dispersion and distribution of SDCNFs and MAPP in the PP matrix. It was concluded that the tensile and flexural properties increased as the particle size of SDCNFs increased, and the impact strength increased as the particle size decreased. The tensile strength, tensile modulus, flexural strength, flexural modulus, and impact strength increased by up to 29 %, 66 %, 15 %, 27 %, and 11 % respectively, compared to the neat PP after adding 10 wt% of SDCNFs with MAPP to the PP matrix.

Pertumbuhan Beberapa Galur Ayam Lokal Fase Starter Yang Dipelihara Pada Kandang Slat Dan Litter

Animals with genetic abilities along with the environment will express different phenotypes (P = G + L + GL). The research was conducted for 1 month in the Amahusu people's livestock business, Ambon City. The livestock used were the starter phase, totaling 72 heads aged 3 weeks with an average initial weight of 80 grams. Tools used: digital scales, places to eat, drink, cages, hygrometer, thermometer. Cages used: 12 floors of slat and 12 floors of litter measuring 50 x 50 M, drinking water, litter (wood pulp), commercial feed. The research method is an experimental method using a completely randomized design (CRD) factorial pattern (3x2x4). Factor G is a strain consisting of 3 levels: 1. G1 = Arabic chicken, 2. G2 = Super chicken, 3. G3 = Free-range chicken, with female sex Factor L is the type of cage which consists of 2 levels, namely: 1. L1 = slat floor; 2. L2 = litter floor. Animal feed consumption had a significant effect on floor type (P<0.05) and lines had a very significant effect (P<0.01), drinking water consumption, body weight gain and feed conversion did not have a significant effect on chicken growth. village. There was no effect of strain interaction with floor type, but the average feed consumption results showed the highest interaction was in G1L2 and the lowest score was in G3L2, while the average PBB of lines with floor type showed the highest interaction in G2L1 of 74.87 while the lowest G3L2 was 58.75 grams. The highest body weight gain on the slat floor was an average of 70.20 grams per head/week, for the super lines was 72.56 grams while efficient feed conversion was 4.48 and 4.48 litter floors. super strain 3.8 gram.
 

Next-Generation Cellulosic Filaments from Hemp Pulp via Dry-Jet Wet Spinning Using HighPerCell® Technology

Fiber demand of cellulosic fibers is rapidly increasing; however, these fibers are mainly based on the use of wood pulp (WP), which often have long transport times and, consequently, a high CO2 footprint. So, alternative pulps based on non-wood, annual fast-growing plants are an option to cover the demand for raw materials and resources. Herein, we report on the use of a novel developed hemp pulp (HP) for man-made cellulosic fiber filament spinning. Commercial WP was used as a reference material. While HP could be used and directly spun as received without any further pretreatment, an additional step to adjust the degree of polymerization (DP) was needed to use the wood pulp. Continuous filaments were spun using a novel dry-jet wet spinning (HighPerCell® process) technique, which is based on the use of 1-ethyl-3-methylimidazolium octanoate ([C2C1im][Oc]) as a solvent. Via this approach, several thousand meters (12,000 m–15,000 m) of continuous multifilament filaments were spun. The HP pulps showed excellent spinning performance. The novel approach allows the preparation of cellulosic fibers for either technical—with high tensile strength—or textile—possessing a low fibrillation tendency—applications. Textile hemp-based filaments were used for first weaving trials, resulting in a flawless fabric.

A wood pulp sponge cleaning wipe as a high-performance bioanode material in microbial electrochemical systems for its vast biomass carrying capacity, large capacitance, and small charge transfer resistance

Microbial electrochemical systems are a promising green and sustainable technology that can transform waste into electricity. Improving conversion efficiency and lowering system costs, particularly for electrodes, are the primary directions that promote practical application. Cellulose sponges made from wood pulp have been industrially mass-produced in various application scenarios due to their porosity and green sustainability. In this study, the three-dimensional (3D) porous cellulose sponges carbon (CSC) was obtained by directly carbonizing cellulose sponges at different temperatures (600, 700, 800, 900, 1000, and 1100 °C). It has been successfully used as a high-performance anode in microbial fuel cells (MFCs). The carbonization temperature significantly impacted the materials’ specific surface area, conductivity, and capacitance. The greater the anode material's carbonization temperature, the lower the charge transfer resistance and the higher the maximum power density (CSC-1100, 4.1 ± 0.1 W m–2). The CSC-700′s maximum power density (3.62 ± 0.11 W m–2) was the highest power density reported to date among lignocellulose-based anodes with relatively low energy consumption. The pleated multilayer porous surface promotes microbial adhesion and can build thicker biofilms with the highest biomass of 2661 ± 117 μg cm–2 (CSC-1100) and containing 86 % electrogenic bacteria (Geobacter). To investigate the effect of conducting polymers on the material's surface, we introduced polyaniline and polypyrrole. We found that the CSC-1000/PPy bioanodes produced a maximum power density (4.18 ± 0.05 W m–2), slightly higher than of without polypyrrole-modified (CSC-1000, 3.99 ± 0.06 W m–2), indicating that the CSCs anode surface had excellent electron transfer efficiency and could achieve the same amount of energy as the polypyrrole surface. This study introduced a promising method for fabricating high-performance anodes using low-cost, industrialized, and sustainable materials.

Fabrication of negative magnetostrictive Japanese traditional paper (washi) with cobalt ferrite particles

The cellulose fibers that form washi are longer than those of regular paper made from wood pulp. Hence, the mechanical properties of washi can be higher than those of conventional paper. This study evaluated the magnetic, magnetostrictive, and tensile properties of negative magnetostrictive cobalt ferrite (CoFe2O4) particle dispersed handmade washi (washi−CoFe2O4). The CoFe2O4 additives magnetized the washi, which displayed negative magnetostriction with the fiber direction perpendicular to the magnetic field and in the parallel fiber direction. Concerning the mechanical properties, the washi−CoFe2O4 displayed an elongation of up to 77% after yielding.

Wood Fibre Properties and Genetic Divergence in Haldina cordifolia (Roxb.) Ridsdale

Haldina cordifolia is a multipurpose tree species. It is one of the best Indian timbers suitable for flooring, panelling and for railway carriages. It is also suitable for pulp and paper, construction, window frames, furniture, bobbins, piano keys and rulers. Wood is also used for pencil manufacturing. Though many phyto-chemicals and pharmacological compounds have been identified from this tree species, the species has not been domesticated so far. ICFRE-Institute of Forest Genetics and Tree Breeding, Coimbatore has initiated a tree improvement programme in this tree species since 2018 and plus trees numbering 141 have been selected from the state of Kerala. Eucalyptus spp., Casuarina spp., and Poplars are the major sources of wood pulp used by the paper industries in India. Efforts are being undertaken by various research institutions in India to find alternate indigenous tree species suitable for pulp. Therefore, a study was undertaken to understand the wood fibre properties of select Plus Trees of H. cordifolia. Wood samples collected from 30 select plus trees have been subjected to wood fibre analyses and genetic divergence studies. Wood specific gravity varied from 0.62 to 0.71. Various wood fibre ratios were also studied. Among the 30 Plus Trees studied, HC 01, HC 03, HC 04, HC 05, HC 18, HC 26 and HC 27 have registered ideal values for using them for paper making. The maximum value for broad sense heritability was recorded by Felting coefficient (0.75). Coefficient of fibre flexibility, Isenberg coefficient, Runkel’s ratio and Lumen diameter also registered reasonably higher values for H2. Application of Mahalanobis’ D2 statistics and Tocher’s clustering method resolved 30 Plus Trees into 6 clusters. The cluster strength varied from one in cluster 6 to 21 in cluster 1. The remaining 4 clusters contained two trees each. Genetic divergence studies have shown that Plus Trees namely, HC 22, HC 23, HC24, HC 27, HC 28, HC 29 and HC 30 could be utilized for further tree breeding programmes.

Kaplanmış ve Kaplanmamış Kağıtların Baskı Kalitesine Etkisini Belirleyen Parametrelerin Analizi

Both paper and ink are the two main raw materials in the manufacture of printed materials. The visual quality of the printed product is very important. Printing an image on paper with ink in high resolution is dependent on the quality of the interfacial relationship between paper and ink. Newsprint, book paper, and pure cellulose-based high-grade paper pulp where the mechanical wood pulp is intensively utilized have porous structures. Coldset offset printing is used for printing on these papers. The coldset offset printing is a printing process where drying occurs late by evaporation of the liquid portion of the ink and absorption into the paper. The ink can sometimes take several days to dry completely (solidify). During this drying process, the ink penetrates the cellulose capillaries in the paper in the vertical direction and behaves the same in the horizontal direction. The dot diameter, which mechanically grows due to the printing pressure (dot gain), grows even larger by spontaneous micro-steps during the drying process. It tends to cross to the back surface of the paper in a vertical direction. For this reason, the paper-ink interfacial behavior is a critical parameter that should be maintained under control as much as possible. The rough surface, porous structure and humidity of the paper, the viscosity and amount of ink printed on the paper surface, the printing pressure at the NIP point, and the physical conditions of the printing room are influential in this interfacial relationship. 
 In this study, the factors that affect the image quality in printing on uncoated and coated papers were investigated by test printing. The CMYK test scale, which was specially prepared for the examination of print quality, was printed with Coldset Offset Printing on smooth papers coated with woodfree coated paper and woodfree uncoated paper, which are the best examples of uncoated papers and are widely used especially in book production. After printing, the surface of the papers was measured with a spectrophotometer and the dot growth and trapping values were determined. Surface and interfacial images of the prints were taken with a stereoscopic microscope and visual examinations were undertaken.

Paper-Based Hydroelectric Generators for Water Evaporation-Induced Electricity Generation.

The research presented in this paper introduces a novel environmental energy-harvesting technology that harnesses electricity from the evaporation of water using porous structural materials. Specifically, a strategy employing paper-based hydroelectric generators (p-HEGs) is proposed to capture the energy produced during water evaporation and convert it into usable electricity. The p-HEGs offer several advantages, including simplicity in fabrication, low cost, and reusability. To evaluate their effectiveness, the water evaporation-induced electrical output performance of four different p-HEGs are compared. Among the variants tested, the p-HEG combining wood pulp and polyester fiber exhibits the best output performance. At room temperature, this particular p-HEG generates a short-circuit current and open-circuit voltage of ≈0.4µA and 0.3V, respectively, thereby demonstrating excellent electrical stability. Furthermore, the electrical current and voltage generated by the p-HEG through water evaporation are able to power an LED light, both individually and in series and parallel connections. This study delves into the potential of electricity harvesting from water evaporation and establishes it as a viable method for renewable energy applications.

Regenerated cellulose membranes for efficient separation of organic mixtures

Organic solvent nanofiltration (OSN) is a low-carbon technology for organic mixture separation that usually relies on non-renewable fossil-derived membranes. Cellulose, a biomass material with extensive sources and superior resistance to organic solvents, holds great promise in engineering OSN membranes. Here we studied the mass transport and separation properties of regenerated cellulose membranes (RCMs), which were made from wood pulp using ionic liquid as solvent by phase inversion method. By regulating membrane thickness from 150 μm to 350 μm, the solvent permeance and solute rejection can be finely tuned. The 350-μm-thick RCM membrane (RCM-350) displays better compaction resistance than the thinner ones and harvests high solute rejection with ethanol permeance reaching ∼ 30 L m−2 h−1 bar−1, outperforming the state-of-the-art polymeric membranes and showing long-term stability during cross-flow OSN. When used for solute separation, the RCM-350 membrane provides molecular selectivity of up to 294 and 68 for Alcian blue/Rifampicin and Alcian blue/Tetracycline mixtures, respectively, which depends on the mixture composition. Our findings reveal the potential of regenerated natural cellulose as a high-performance and sustainable alternative membrane material for separating organic mixtures.

The Effect of Cellulose Nanofibres on Dewatering during Wet-Forming and the Mechanical Properties of Thermoformed Specimens Made of Thermomechanical and Kraft Pulps.

Due to environmental concerns regarding single-use plastic materials, major efforts are being made to develop new material concepts based on biodegradable and renewable resources, e.g., wood pulp. In this study, we assessed two types of wood pulp fibres, i.e., thermomechanical pulp (TMP) and Kraft pulp fibres, and tested the performance of the fibres in wet-moulding and thermopressing trials. Kraft pulp fibres appeared to retain more water than TMP, increasing the dewatering time during wet-moulding and apparently increasing the compression resistance of the pulp during thermoforming. Additionally, cellulose nanofibres (CNF) were added to the pulps, which improved the mechanical properties of the final thermopressed specimens. However, the addition of CNF to the pulps (from 2 to 6%) had a further decrease in the dewatering efficiency in the wet-moulding process, and this effect was more pronounced in the Kraft pulp specimens. The mechanical performance of the thermoformed specimens was in the same range as the plastic materials that are conventionally used in food packaging, i.e., modulus 0.6-1.2 GPa, strength 49 MPa and elongation 6-9%. Finally, this study demonstrates the potential of wood pulps to form three-dimensional thermoformed products.

Rubberwood—Potential for Pulp and Composite Board Utilization

Rubberwood (Hevea brasiliensis Muell. Arg) is underutilized in most developing countries but has potential to be a solution to the shortage of wood for pulp, paper and wood composite products at the end of its production cycle. Determining and understanding its fibre properties (fibre dimensions and morphology) is key in its utilization for pulp and paper as well as composites. This study assessed the effect of age on the fibre properties of rubberwood. Samples of wood at four ages (10, 15, 20 and 25 years) were obtained at both the axial (base and top of merchantable length) and radial direction (innerwood, middlewood and outerwood). Slivers were obtained from the samples and macerated to provide individual fibres for optical measurement. Fibre dimensions at the four ages were measured, and their morphology was determined. Fibre properties and morphology were significantly affected by age at p = 0.05. Average fibre length was 1.47 ± 0.12 mm, with non-constant variation observed across the different ages, and from pith to bark. Average lumen width was 16.87 µm, and fibre diameter ranged from 25.02 µm to 27.23 µm. The fibre properties of rubberwood potentially make it suitable for pulp and paper production as well as wood composite boards.

Wood waste valorization: Ethanol based organosolv as a promising recycling process

Wood waste is a valuable material that could constitute an abundant and inexpensive source for the production of new materials the recovery of energy. In Europe, about 46% of wood waste is recycled to particleboard and fiberboard, while the other fraction is incinerated. However, a considerable quantity of wood waste shows potential for its transformation into value-added products due to its compositional quality. In this work, wood waste collected at a mechanical treatment plant underwent organosolv treatment to produce a cellulose pulp suitable for manufacturing containerboard. Three variables (temperature, acid concentration, and ethanol concentration) were investigated to find an optimal solution to produce wood pulp by means of Design of Experiment. Wood waste was microwave-heated at 160 °C for 15 min using an acidified ethanol–water solution (2% w/w H2SO4 and 0.8 w/w ethanol concentration), producing pulp with an average cellulose content of 76% where 93% of initial cellulose was retained. Thanks to a one-pot approach, ethanol was totally recovered, 62% of initial lignin was precipitated, and 20 g/l of hemicellulose-derived sugars solution was obtained. Finally, three wood waste samples collected in different periods of the year yielded comparable outcomes, suggesting a good reproducibility of the organosolv process. ANOVA test with a significance level of 0.01 showed a p-value of 0.029 and 0.235 for cellulose content and cellulose recovery, respectively. This study paves the way for an industrial symbiosis between recycling centers and paper mills located in the same territory.