Volume 14 Issue 1
- Editorialpp 1-2Hubbe, M. (2019). "BioResources to serve as host for Fundamental Research Symposia archives," BioRes. 14(1), 1-2.AbstractPDF
The Fundamental Research Committee (FRC), founded in 1956 to organize regular symposia among pulp and paper scientists, has been aiming to widen access to their archival published proceedings. The FRC decided that it would be best to make their published work freely available on the web rather than continuing to offer CD versions for sale. They wanted to work together with an entity having experience with open access publishing. The FRC has selected BioResources as that entity, based on our 13-year record of open access service to the same branch of science and technology. BioResources is honored to take on this role and accordingly will henceforth prominently list the “Fundamental Research Symposia Archives” on our web page with links to the FRC content.
- Editorialpp 3-5Chen, Z., Zhang, H., He, Z., Zhang, L., and Yue, X. (2019). "Bamboo as an emerging resource for worldwide pulping and papermaking," BioRes. 14(1), 3-5.AbstractPDF
As a widely distributed and fast growing graminaceous plant, bamboo has emerged as an important raw material for pulping and papermaking to mitigate the shortage of wood resources, at least in the East Asia region. New technologies such as silicon removal have been developed to overcome the disadvantage of bamboo as a pulping raw material, as well as to improve the quality of bamboo pulp products. The bamboo pulping capacity in China is continuing to increase in the near future.
- Researchpp 6-20Nurek, T., Gendek, A., and Roman, K. (2019). "Forest residues as a renewable source of energy: Elemental composition and physical properties," BioRes. 14(1), 6-20.AbstractPDF
Forest residues are a potentially important source of renewable energy. They are generated as a byproduct of timber harvesting around the world. To optimize the utilization of such biomass, one must know its physical and chemical properties. This paper presents an analysis of comminuted forest residues from Pinus sylvestris L. They were classified into four size fractions for which three density parameters were established pursuant to relevant standards. The mean bulk density of the fractions amounted to 110 to 190 kg/m3, apparent density 725 to 908 kg/m3, and specific density 1111 to 1350 kg/m3. The findings were compared to the results of previous research on other forms of forest biomass. The measured apparent-to-specific density conversion coefficient was β = 0.64. The elementary composition of forest residues measured in this work differed from that of other biomass types described in literature. In terms of carbon, nitrogen, sulfur, oxygen, and ash content, statistical analysis showed that the two compared types of biomass (forest residues and energy wood chips) formed two separate homogeneous groups, while both of these materials constituted one homogeneous group in the case of hydrogen content. The calorific value of the forest residues was 15.78 ± 0.39 MJ/kg.
- Researchpp 21-30Liu, S., He, H., Fu, X., Yuan, T., Wang, Q., Yang, G., Zhang, H., Ding, M., and Liao, C. (2019). "Xylitol production from prehydrolysis liquor of kraft-based dissolving pulp by Candida tropicalis," BioRes. 14(1), 21-30.AbstractPDF
Xylitol production from the hemicelluloses of prehydrolysis liquor (PHL) is of practical interest from both economic and environmental standpoints. The removal of the inhibitors, e.g., lignin, acetic acid, and furfural, is the key to improving the conversion of xylose to xylitol when Candida tropicalis fermentation is used. For this purpose, a full chain process involving activated carbon adsorption, ion exchange resin treatment, acidolysis, and fermentation was considered in this work. The results showed that 72.6% of lignin and 67.1% of furfural were removed using an activated carbon dosage of 20 mg/g PHL. Additionally, 61.2% of acetic acid was also removed at a resin dosage of 100 mg/g PHL. Subsequently, acidolysis using sulfuric acid and pH adjustment with lime was performed on the treated PHL to convert the oligosaccharides into monosaccharides; a yield of 0.40 g xylitol/g xylose was achieved via treating the PHL with Candida tropicalis fermentation at 30 °C, 200 rpm, and 96 h. In addition, a material balance was determined for the full chain process.
- Reviewpp to be addedLopes, D. J. V., Stokes, E. C., and dos Santos Bobadilha, G. (2019). "The use of chemical and biological agents in the recovery of heavy metals from treated woods – A brief review," BioRes. 14(1), Page numbers to be added.AbstractPDF
This manuscript provides a brief review about chemical and biological agents used to bioremediate treated wood waste. Wood preservatives have been used to increase wood’s useful life, because any species is subject to decay. Studies indicate that the disposal of treated wood after its service has drawn concern and scrutiny. Practices have included disposal in landfills or construction sites as well as destruction by burning, so it is apparent that more environmentally friendly options are needed. To mitigate these problems, acidic agents, fungi, and bacteria can be used as alternatives to remove heavy metals. At optimum temperature and concentration, acids play a major role in the removal process. The process is enhanced when a bioremediation technique is used after chemical extraction. In fact, bioremediation has been shown to be a remarkable technique for recovering copper, arsenic, creosote, and other compounds. The major drawback is the extensive duration of fungal activity for release of heavy metals.
- Researchpp 31-43Domingos, I., Fernandes, A., Ferreira, J., Cruz-Lopes, L., and Esteves, B. (2018). "Polyurethane foams from liquefied Eucalyptus globulus branches," BioRes. 14(1), 31-43.AbstractPDF
Currently, polyurethane (PU) production is completely dependent upon fossil oil, as the two primary reagents necessary for PU production, polyol and isocyanate, are derived from fossil fuels. Eucalyptus branches are waste products for most forest management companies. In this work, polyols obtained by the liquefaction of eucalyptus branches were used for foam production. The influence of the isocyanate, catalyst, surfactant, and blowing agent contents on the foam properties was studied. Overall the amount of each chemical used in the production of PU foams had a noticeable effect on the density and compressive properties. The amount of water (blowing agent) had the strongest effect and decreased the density and compressive properties because of higher foam expansion. The other chemicals increased or decreased the density and compressive stress depending on the amount used. The density of the produced foams ranged from 36 kg/m3 to 108 kg/m3, the compressive stress ranged from 15 kPa to 149 kPa, and the Young’s modulus ranged from 64 kPa to 2100 kPa. The results showed that it is possible to convert these forest residues into PU foams with properties somewhat similar to those of commercial foams, although with a lower compressive strength.
- Researchpp 44-58Huang, S., Ma, Z., Nie, Y., Lu, F., and Ma, L. (2019). "Comparative study of the performance of acetylated bamboo with different catalysts," BioRes. 14(1), 44-58.AbstractPDF
The catalytic acetylation of bamboo (Phyllostachys pubescens) was compared with acetylation using concentrated sulfuric acid, acetic acid, potassium acetate, and noncatalytic acetylation at 120 °C for 3 h. The weight percentage gain, dimensional stability, color difference, and wettability of bamboo after the acetylation was comprehensively measured. Also, the chemical and thermal properties of the resultant bamboo were characterized by Fourier transform infrared spectroscopy (FTIR) and thermogravimetric (TG) analysis. The results showed that the potassium acetate-catalyzed acetylation of bamboo greatly accelerated the reaction degree, had little effect on color change, extraordinarily decreased wettability, and had little irregular impact on the dimensional stability. The catalytic activity was followed by potassium acetate, sulfuric acid, noncatalytic acid, and acetic acid. The FTIR analysis showed that the functional groups in the acetylated bamboo were mainly affected by different catalysts. The thermal stability of acetylated bamboo was higher than the untreated bamboo. In particular, potassium acetate-catalytic acetylation greatly reacted with -OH groups and increased thermal decomposition.
- Researchpp 59-69Wang, L., He, C., and Yang, X. (2019). "Effects of pretreatment on the soil aging behavior of rice husk fibers/polyvinyl chloride composites," BioRes. 14(1), 59-69.AbstractPDF
The application of rice husk fibers (RHFs) to reinforce wood plastic composites has received appreciable attention. However, good interfacial adhesion is important for actual applications. Pretreatment methods can reduce the hydroxyl groups in plant fibers in order for them to bond with the plastic matrix. In this research, RHFs were pretreated by four methods: hydrothermal treatment (HT), microwave treatment (MT), alkali treatment (AT), and benzoylation treatment (BT). The effects of the four pretreatment methods on aging behavior of RHFs/polyvinyl chloride (PVC) composites was studied with simulated soil-accelerated aging conditions. Accelerated-soil aging caused the physical and mechanical properties of the composites to deteriorate. The ultimate performance of the composites was improved by the pretreated RHFs. The effectiveness ranking of the pretreatment methods was: benzoylation-treated RHFs reinforced PVC (BRRP) > alkali-treated RHFs reinforced PVC (ARRP) > hydrothermal-treated RHFs reinforced PVC (HRRP) > microwave-treated RHFs reinforced PVC (MRRP) > untreated RHFs reinforced PVC (URRP).
- Researchpp 70-86Hu, Z., Xiang, Z., Song, T., and Lu, F. (2019). "Effects of crosslinking degree on the coating properties of arabinoxylan," BioRes. 14(1), 70-86.AbstractPDF
Arabinoxylan (AX) was extracted from sugarcane bagasse and modified through crosslinking with glutaraldehyde (GA). The effects of crosslinking degree on the rheological and coating properties of glutaraldehyde crosslinked arabinoxylan (GAX) were investigated. To better evaluate the degree of crosslinking, the crosslink index was used to represent the degree of crosslinking for the GAX in this study. The viscosity of the GAX solution increased when the degree of crosslinking increased, and the solution demonstrated non-Newtonian flow behavior. A high degree of crosslinking was detrimental to the film and coating properties of the GAX. At an optimum degree of crosslinking, the tensile strength of the GAX films increased by approximately 170% and 60% compared with that of the AX and GAX with the highest degree of crosslinking, respectively; the tensile strength of the GAX-coated paper increased by approximately 15% compared with that of the GAX with the highest degree of crosslinking. When calcium carbonate was mixed with the paper coating adhesives, the GAX showed comparable coating properties to that of polyvinyl alcohol, demonstrating its potential to substitute petroleum-based paper coating adhesives.
- Researchpp 87-98Yang, R., Wang, X., Zhang, Y., Mao, H., Lan, P., and Zhou, D. (2019). "Facile synthesis of mesoporous silica aerogels from rice straw ash-based biosilica via freeze-drying," BioRes. 14(1), 87-98.AbstractPDF
The combustion of biomass fuels has been a significant source of global energy, and about 10 million tons of straw are used annually, yielding at least 0.5 million tons of straw ash. However, the ash from rice straw has rarely been reused, thereby contributing to environmental pollution. A new approach is reported for preparing mesoporous silica aerogels using straw ash-based biosilica via a sol-gel process and vacuum freeze-drying. The mesoporous structure, porosity, pore volume, and specific surface area of this straw ash-based aerogel had satisfactory values. Effects of pH on the synthesis of silica aerogel were investigated to better understand the most important factors influencing the gelation, final structure, physicochemical properties, morphology, and thermostability of the samples.