Volume 10 Issue 1

The effects of particle size and geometry on the physical (density, water absorption, and thickness swelling), thermal, and mechanical (modulus of elasticity, bending strength, internal bond strength, and screw holding strength) properties of single-layer and three-layer particleboards made from sunflower seed husks were investigated. Panels manufactured from particles with various sizes using a urea-formaldehyde adhesive had densities ranging from 535 to 682 kg/m3. The adhesive ratio was at a level of 16% for the single-layer mat configuration; for the three-layer structure, levels of 14% for the core and 16% for the faces were used, based on the weight of particles. The best results occurred in single-layer particleboard made from fine particles, which nearly met the general purpose requirements of the EN 312 Standard. Determination of the thermal conductivity coefficient demonstrated good insulation properties of all panels and their potential use for different structural configurations which are not subjected to strong stresses, suitable for interior design.

Measurements of air permeation rate were taken according to EN 12114 for OSB boards, which were manufactured ​​for this purpose in accordance with the requirements of EN 300 by a commercial manufacturer. The study measured the air permeation rate of samples and evaluated the influence of selected parameters on the resulting values. The effects of these factors on the rate of air permeation were specified, showing the particular influences of board thickness (12 mm and 18 mm) and type (OSB/3 and OSB/4). The dependence of the measured values ​​of air permeation rate on the pressure difference was described using linear equations within a regression analysis. The group of OSB/3 samples exhibited a lower resistance to air permeation than OSB/4 (about 61% for both thicknesses). In addition, in both groups, 18 mm samples showed a higher resistance to air permeation than samples with a thickness of 12 mm (OSB/3 by about 40% and OSB/4 by about 41%).

In order to obtain a material that exhibits a better tensile strength, UV absorption, and transparency, lignocellulose of eucalyptus was dissolved and subsequently regenerated in ionic liquid (IL) following treatment with different pretreatment conditions. The effect of 1,4-dioxane extraction concentration was evaluated by comparing the chemical, thermal, mechanical, and optical performance of the obtained films. The results indicated that lignocellulose could be dissolved using the IL, with the regenerated film demonstrating obvious signs of phase separation. Increasing the 1,4-dioxane extraction concentration brought about an increase in the degree of crystallization, tensile stress, and ultraviolet-visible light transmittance of films. However, the lignin content and peak temperature of main decomposition for the films decreased. Compared to cellulose film, lignocellulose film showed excellent UV absorption properties due to the presence of lignin. F-90 possessed of a better tensile strength, UV absorption, and transparency. This work demonstrated the possibility that a biodegradable green functional film can be prepared.

Simultaneous saccharification and fermentation (SSF) is an attractive process configuration for bio-ethanol production. Further reductions in process cost of SSF are expected with the use of waste agricultural or industrial materials as feedstock. In the current study, two industrial lignocellulosic wastes, cassava residues (CR) and furfural residues (FR), were combined during SSF for ethanol production due to their value-added applications and positive environmental impacts. After CR were liquefied and saccharified, saccharification liquid was added to SSF of FR. The effect of substrate fractions was investigated in terms of ethanol yield, byproduct concentration and the number of yeast cells. Besides, a natural surfactant, Gleditsia saponin, was added to investigate the effect of FR lignin on SSF with 20% substrate concentration. The results showed that increasing the ratio of CR/FR improved the ethanol yield and that the ethanol yield was also increased gradually by increasing the substrate concentration from 6% to 12%. A high ethanol concentration of 36.0 g/L was obtained under the condition of CR:FR = 2:1 with 12% substrate concentration, reaching 71.1% of the theoretical yield. However, Gleditsia saponin did not affect the ethanol yield, indicating the insignificant effect of lignin in SSF with low lignin content in the reaction system.

In a previous study the authors determined that non-woody materials including brewers’ grain (BG) and oil palm frond (OPF) could be alternatives to wood powder as organic fillers. However, they have the disadvantage of deteriorating the strength of paperboard. If the strength of paperboard could be improved, then one would expect more production cost reductions and bulk improvements by increasing the addition of organic fillers. In this study, surface modification of organic fillers was used as a method to improve paperboard strength. The goal was to find the most effective condition for surface modifications. Surface modifications of BG and OPF fillers were carried out using cationic and oxidized starches, and the strengths and reductions in the drying energies of the sheets were measured. The zeta potentials of the modified organic fillers showed that the surface modifications were performed properly. Surface modification with starches improved the bulk and strength of the sheets simultaneously, and modification with the addition of a large amount of cationic starch was more effective in improving the strengths and the reductions in drying energies of the sheets than using cationic and oxidized starches together.

Linting occurs when small particles are removed from the paper surface by the splitting of the tacky ink film. Excessive linting reduces printing quality and can affect the pressroom efficiency. An improved method, using video camera technology, has been utilized to measure the dynamics of linting during the printing process. This technology makes it feasible to estimate the removal of lint particles from the paper and from the blanket surfaces. This article presents the latest development of the lint camera system and its applications under different press conditions, including ink color. The lint measurements obtained by the camera system were compared with the established measurement methods (blanket tape pull and blanket wash). The main result from this study indicates some similarities in the lint area distribution measured by the camera system and the blanket tape pull. The differences in the lint area distribution from the filtered sample at small particle sizes is likely due to disaggregation of the agglomerated lint particles during the washing and filtering, and as a result, of more small particles being measured from the tape pulls.

To extend the potential application of ultrasonic treatment in dyeing low-quality wood to improve decorative value, wood veneers were dyed with an ultrasonic assisted dyeing system. The effects of ultrasonic power, dye concentration, dyeing time, and temperature of ultrasonic-assisted treatment on dye-uptake, chromatic value, crystallinity, thermal stability, chemical structure, and microstructure for dyed wood veneer were investigated. The dye-uptake, chromatic value, and dyeing rate were improved by ultrasonic-assisted treatment. The effect was strengthened with an increase in ultrasonic power, dye concentration, and dyeing time and temperature. After ultrasonic treatment, the dyed wood properties such as lignin degradation, crystallization and thermal stability decreased slightly, and part of the wood microstructure such as the pit membrane and parenchyma cells was mechanically damaged. Ultrasonic-assisted treatment enhanced the permeability of wood by creating new fluid channels and sorption sites, and it is believed to be an energy-efficient and environmental wood dyeing technique.

This study compares the efficacy of a soaking pretreatment with an alkaline solution for banana pseudostem prior to enzymatic hydrolysis. Banana pseudostem was pretreated by soaking in sodium hydroxide solutions at various concentrations and durations. The pretreatment more than doubled delignification but retained 82.09% of the holocellulose content and 73.74% of the cellulose content. The enzymatic (Trichoderma reesei) digestibility of pretreated banana pseudostem was found to have been enhanced by 44.41% as compared to initial biomass. This was evidenced by higher enzymatic activities (endoglucanase, exoglucanase, and β-glucosidase) on the treated sample. Meanwhile, glucose yield showed a proportional relationship with incubation time and enzyme loading throughout the hydrolysis process.

U.S. hardwood sawmill log procurement practices are evolving because of the recent economic recession, market and supply chain shifts, and changing landowner objectives, among other factors. The objective of this study was to characterize the log procurement practices of hardwood sawmills and to characterize the role that log brokers play in supplying the sawmill industry with raw material. To meet this objective, a mail survey on hardwood log procurement practices in the U.S. hardwood sawmill industry was conducted. Survey respondents highlighted several factors that had major effects on their businesses, including “Increasing fuel and trucking cost,” “High logging cost,” “Unpredictable log supply,” “Log shortages,” “Logger shortages,” and “Low log quality,” among others. Results showed that large sawmills tend to rely more on gatewood from loggers and stumpage harvested by company contract loggers than do small- and medium-sized sawmills. This study failed to find an increase in the role of log brokers as an intermediary between landowners and hardwood sawmills during the last decade. Moreover, sawmills indicated only a limited demand for log broker services, with log delivery and the procurement of specialty logs identified as being the most highly demanded broker services.

Cadium sulfide/titanium dioxide (CdS/TiO2) catalyst was prepared by two different methods: microemulsion-mediated solvothermal hydrolyzation (CdS/TiO2 (SH)) and in-situ sulfurization under supercritical conditions (CdS/TiO2 (SS)). The photocatalysts were characterized by nitrogen adsorption-desorption, X-ray diffraction, X-ray photoelectron spectra, UV-Vis absorption spectra, and PL spectra. Photodegradationreactions of three monomeric and one dimeric lignin model compounds, and kraft pine lignin (Indulin AT) were carried out at room temperature in a weak alkaline aqueous system by visible light irradiation with air bubbling. Quantitative results showed that these lignin model compounds and kraft lignin were effectively degraded. While both phenolic and non-phenolic lignin units are reactive, the phenolic units appeared to react faster and preferentially reacted.