NC State
  • Researchpp 7916-7934Aluvihare Gedara, A. K., Chianella, I., Bhattacharyya, D., Endrino, J. L., and Zhang, Q. (2021). "Alkali-treated wheat gluten cross-linked with sodium alginate as a bio-based wood adhesive for interior grade particleboard," BioResources 16(4), 7916-7934.AbstractPDF

    A bio-based wood adhesive formulation free of formaldehyde and made from alkali-treated wheat gluten (WG) and sodium alginate (SA) was developed. Its formulation was optimised, and it was characterised by Fourier Transform Infrared (FT-IR) spectroscopy. The bio-adhesive was utilized to make particleboards both with virgin wood particles and recycled wood particles. A dry bio-adhesive content of 35% (w/w) was used to make samples with both type of particles. Single-layer samples of 10 mm thickness were obtained using wood particles of 1 mm (both virgin and recycled). These samples then were subjected to 3-point bending tests. Whereas the bending strength of samples made with recycled wood particles was 18.09 N/m2 and therefore satisfied Type 18 of the Japanese industrial standards (JIS A 5908:2015), the bending strength of the samples made with virgin wood particles was 8.08 N/m2 and satisfied ‘Type 8 Base particleboard Decorative particleboard’ of the Japanese standards. The density of particleboard samples made from recycled wood particles was 916 kg/m3, while that of samples made from virgin wood particles was 732 kg/m3. The alkali-treated WG and SA bio-adhesive has the potential to be used to re-manufacture particleboards, which can then be recycled and not disposed in landfills.

  • Researchpp 7935-7952Tsalagkas, D., Börcsök, Z., Pásztory, Z., Gryc, V., Csóka, L., and Giagli, K. (2021). "A comparative fiber morphological analysis of major agricultural residues (used or investigated) as feedstock in the pulp and paper industry," BioResources 16(4), 7935-7952.AbstractPDF

    The suitabilities of major agricultural residues were assessed as papermaking feedstocks. All the examined agricultural residues were assumed as potential candidates for substituting hardwood fibers in mixed pulp blends from a fiber morphological perspective. Wheat, barley, rice, rapeseed, maize, sunflower, sugarcane bagasse, coconut husk, and two genotypes of miscanthus grass underwent identical maceration. The fiber length, fiber width, cell wall thickness, and lumen diameter were measured to calculate the slenderness ratio, flexibility coefficient, and Runkel ratio. The average fiber length ranged from 0.50 mm ± 0.32 mm (MG-S-02-V) to 1.15 mm mm ± 0.58 mm (sugarcane bagasse). The fiber width ranged from 10.77 μm ± 3.28 μm (rice straw) to 22.99 mm ± 5.20 mm (sunflower stalk). The lumen diameter ranged from 4.52 μm ± 2.52 μm (rice straw) to 13.23 μm ± 4.87 μm (sunflower stalk). The cell wall thickness ranged from 3.02 μm ± 0.95 μm (rice straw) to 4.80 μm ± 1.48 μm (sunflower stalk). The slenderness ratio, flexibility coefficient, and Runkel ratio values ranged between 28.08 to 58.11, 37.97 to 60.8, and 0.62 to 1.68, respectively. Wheat, maize, rapeseed, sugarcane bagasse, and coconut husk were found to be appropriate residue sources for papermaking feedstocks.

  • Researchpp 7953-7965Chen, Q., Rong, Z., Liu, Z., You, N., and Xie, G. (2021). "Application of modified phytic acid as flame retardant in cellulosic paper," BioResources 16(4), 7953-7965.AbstractPDF

    A flame retardant containing phosphorus and nitrogen was synthesized using phytic acid and dicyandiamide, and it was subsequently used to prepare flame-retardant cellulosic paper via an impregnation method. Vertical flame and limiting oxygen index (LOI) were used to evaluate the flame retardancy of the paper. The paper containing modified phytic acid was characterized with Fourier transform infrared spectroscopy (FTIR), thermogravimetry (TG), X-ray diffraction (XRD), and scanning electron microscopy (SEM). When the concentration of modified phytic acid was 20%, the char length of the treated paper decreased from 12.5 cm to 4.1 cm, the LOI value increased from 19.6% to 41.5%, and the tensile index was only 3.66% lower than that of the control paper. The modified phytic acid was judged to have good flame-retardant effects on the paper.

  • Researchpp 7966-7990Cachet, N., and Benjelloun-Mlayah, B. (2021). "Comparison of organic acid-based organosolv lignins extracted from the residues of five annual crops," BioResources 16(4), 7966-7990.AbstractPDF

    Organosolv lignins were extracted from corn stover, wheat, rice straw, reed straw, and sugarcane bagasse using a mixture of acetic and formic acids, at relatively low temperature and atmospheric pressure. Lignin content, residual carbohydrates, ash levels, proteins, and molecular weights were determined in each extracted lignin. The lignin content of all samples was relatively high, confirming the performance of the pretreatment process. The low molecular weights were in a narrow range, in accordance with the organosolv lignin molar masses. However, some differences between studied lignins were highlighted, in particular in rice straw lignin, which contained the highest silica, calcium, and nitrogen contents. Nuclear magnetic resonance spectroscopies (31P and semi-quantitative Heteronuclear Single Quantum Correlation) underlined the structural similarities and differences between these organosolv lignins. Corn stover and sugarcane bagasse lignins were rich in non-methoxylated (H-Unit) or mono-methoxylated (G-Unit) phenolic units, making them the best promising candidates for production of phenolic resins. Wheat straw lignin was richer in aliphatic OH than in phenolic OH. This is an advantage for use as polyol substitute in polyurethane synthesis. Reed straw lignin was less specific, with a balanced content of OH groups. However, it contained a high concentration of β-O-4 linkages, which is favorable for depolymerization.

  • Researchpp 7991-8005Kopra, R., Vanhatalo, K., Päärnilä, S., Pappinen, A., and Dahl, O. (2021). "Bleaching microcrystalline cellulose using hydrogen peroxide, peracetic acid, and ozone," BioResources 16(4), 7991-8005.AbstractPDF

    AaltoCell™ based microcrystalline cellulose was bleached using hydrogen peroxide, peracetic acid, and ozone. The target brightness was set at 85% ISO brightness of the sheet (93% Y-brightness), which is white enough for the traditional use of microcrystalline cellulose. Both the paper pulp and dissolving pulp can be hydrolyzed using the AaltoCell™ process. Using paper pulp as a raw material, the brightness of the final microcrystalline cellulose decreased. The higher the temperature and retention time during the hydrolysis process, the greater the brightness loss. This effect can be explained by the so-called caramelization reaction. Due to this phenomenon, the microcrystalline cellulose should be bleached before using the product in food and pharmaceutical applications. The results showed that the target brightness was reached with ozone at doses of approximately 5 kg/ton with a reaction time of a few minutes; peroxide and peracetic acid required approximately twice the dose and a reaction time of at least 30 min. The concentrations of the chemical oxygen demand and total organic carbon in the pulp filtrate fraction varied with the bleaching chemicals used, with both values being low with ozone and the highest with peracetic acid.

  • Researchpp 8006-8021Kukla, M., and Warguła, Ł. (2021). "Wood-based boards mechanical properties and their effects on the cutting process during shredding," BioResources 16(4), 8006-8021.AbstractPDF

    In order to design effective shredding machines dedicated to shredding wood-based waste, information about the mechanical properties of materials subjected to shredding is necessary. A number of mechanical properties of particleboard, oriented strand boards, and medium-density fibreboards in the aspect of shredding process have been experimentally determined in the article. The influence of material type, blade geometries, and cutting depth on cutting force and elasticity coefficient were analysed. Blade geometries reflect different phases of rotation of the cylindrical wood chipper’s knife. It has been shown that a knife with the most favourable geometry is characterized by the lowest values of the stiffness coefficient for each of the materials. This is the geometry of the cylindrical wood chipper’s knife exactly halfway into the cutting process. By contrast, the least favourable geometry is characterized by a knife corresponding to the beginning of the cutting process. Among the tested materials, the medium density board requires the most energy to change its structure, and the laminated particleboard requires the least. The presented results can be a set of input data necessary to model the work required to implement the cutting process, but also enable validation of existing cutting models.

  • Researchpp 8022-8037Chopngam, K., Luengchavanon, M., Khangkhamano, M., Chetpattananondh, K., and Limbut, W. (2021). "Coating activated carbon from coconut shells with Co3O4/CeO2 for high-performance supercapacitor applications: An experimental study," BioResources 16(4), 8022-8037.AbstractPDF

    Activated carbon from coconut shells is a low-cost, environmentally friendly material that is available for fabricating the electrodes for electric double-layer capacitance supercapacitors. As such, activated carbon derived from coconut shells was coated with Co3O4/CeO2, and its electrical and ionic conductivity were evaluated. The ternary technique for selecting materials was systematically investigated with an economical process. The Co3O4/CeO2 coating that was formed on the activated carbon coconut shells was deemed AC-Co3O4-CeO2. The 90-05-05 composite was the best electrode for electric double-layer capacitance supercapacitors, resulting in high conductivity (0.62 x 103 S·cm2), low series resistance and internal resistance (based on the Nyquist plot), and the charge-discharge was able to reach 0.56 V for 90 seconds (1A/g). Therefore, activated carbon coconut shells coated in Co3O4/CeO2 can promote the necessary characteristics of electrodes needed for electric double-layer capacitance supercapacitors.


  • Researchpp 8038-8048Yagüe, M., and Lobo, M. (2021). "Comparison of laboratory methodologies to determine soil nitrogen mineralization from organic residues," BioResources 16(4), 8038-8048.AbstractPDF

    Recycling organic waste for use as fertilizer requires prior knowledge of mineral nitrogen (N) availability for crops. Estimation of soil N release or potentially mineralizable N is an important tool for the design of fertilization strategies that aim to minimize the use of N fertilizer. The aerobic incubation method is considered a standard technique to measure soil potential to mineralize N. In this study, alternative methods of aerobic incubation were evaluated to help overcome its limitations (long time and equipment). In this regard, biological methods (anaerobic incubation at 7 and 14 days) and chemical extraction (hot KCl) procedures were examined. To determine potentially mineralizable N, a silty clay loam soil was fertilized with spent mushroom substrates and anaerobic digestates from different origins (C/N ratio of 4 to 38). Based on the results, chemical extraction emerges as a reliable alternative to the aerobic incubation method, particularly when the C/N ratio of the organic residues ranges from 12 to 15. Moreover, its implementation in routine soil laboratories is straightforward and faster, and it does not require any special equipment.

  • Reviewpp ###-###Hubbe, M. A. (2021). "Energy efficiency challenges in pulp and paper manufacturing: A tutorial review," BioResources 16(4), Page numbers to be added.AbstractPDF

    The pulp and paper industry is highly energy-intensive. In mills that use chemical pulping, roughly half of the higher heating value of the cellulosic material used to manufacture the product typically is incinerated to generate steam and electricity that is needed to run the processes. Additional energy, much of it non-renewable, needs to be purchased. This review considers publications describing steps that pulp and paper facilities can take to operate more efficiently. Savings can be achieved, for instance, by minimizing unnecessary losses in exergy, which can be defined as the energy content relative to a standard ambient condition. Throughout the long series of unit operations comprising the conversion of wood material to sheets of paper, there are large opportunities to more closely approach a hypothetical ideal performance by following established best-practices.

  • Researchpp 8049-8059Acosta, R., Calle Trujillo, G., and Marulanda Arévalo, J. L. (2021). "Synthesis and mechanical behavior of composite material reinforced with Guadua fiber and with a polyurethane or polyester matrix," BioResources 16(4), 8049-8059.AbstractPDF

    A reactive hot-melt resin (polyurethane) was used to manufacture Guadua composites with a certain flexibility, high processing speed, good initial rigidity, and high temperature performance. These composites can support a moderate tensile stress, allow for large strains at low stresses, and have a low density and a working temperature range of -40 °C and 110 °C. During the flexural test, bamboo composites with reactive polyurethane matrix do not break or fail during the test. A polyurethane-based reactive hot-melt resin was characterized by tensile tests, Shore hardness tests, differential scanning calorimetry, and thermogravimetry. Besides, a composite material was made with Guadua fiber and polyester matrix, which had a greater strength in the test of tension and flexion, although it had a lower percentage of elongation than the composite material with reactive polyurethane. Guadua fiber can increase the strength by 266% of polyurethane matrix and 228% of polyester matrix.