Volume 9 Issue 4

To improve the properties of bio-oil, a new method was proposed that does not involve introduction of any energy medium. An ether-soluble fraction (ES), a dichloromethane soluble fraction (DCMS), and a dichloromethane insoluble fraction (DCMIS) of bio-oil were obtained using ether and dichloromethane as extraction solvents. The same amount of each fraction (10 g) was blended into bio-oil with a certain quantity of 100 g. The three samples were then placed in sealed vials and heated for 12, 60, and 180 h at both 60 °C and 80 °C in an oil bath. Based on the aging properties of the three fractions, blended bio-oil was prepared using ES and DCMS in certain volume ratio. The total yield of the three fractions combined was around 90 wt%; the weight loss was thought to be due to the volatilization of low molecular weight matter and water during the process of solvent evaporation using a rotary evaporator. The aging test results indicated that the DCMIS fraction had the poorest properties compared with ES and DCMS such as acid number, water content and viscosity. In order to get the best properties of blended bio-oil, the optimal volume ratio of ES/DCMS was 1/2 according to the aging test.

Downgraded medium density fiberboard (MDF), particleboard (PB), and oriented strandboard (OSB) panels were individually subjected to steam explosion treatment. Downgraded MDF and PB panels were separately treated with thermal chemical impregnation using 0.5% butanetetracarboxylic acid (BTCA). And downgraded PB panels were processed with mechanical hammermilling. The pH, buffer capacity, fiber length, and particle size of these recycled materials were evaluated. After the steam explosion and thermal chemical impregnation treatments, the pH and buffer capacity of recycled urea formaldehyde resin (UF)-bonded MDF and PB furnishes increased and the fiber length decreased. The hammermilling of recycled PB was less likely to break particles down into sizes less than 1 mm2.

To enhance the degradability of cellulosic materials for further industrial purposes, different qualities of cellulose were dissolved in cold sodium hydroxide solution and precipitated by lowering the pH with sulfuric acid. The precipitated cellulose was subjected to acidic and enzymatic hydrolysis. The results showed that the precipitated cellulose degraded considerably faster both with enzymes and acid relative to the untreated controls. Important pretreatment parameters that can influence the degradability of the pretreated cellulosic materials were found to include temperature and concentration of the cellulose in NaOH solution. Increasing amounts of cellulose were hydrolysed with decreasing pretreatment temperature; the degradability of the pretreated cellulose increased with decreasing cellulose concentration. The degree of polymerization (DP) also can influence the pretreatment efficiency. Diluted sulfuric acid was able to decrease the DP and enhance the effect of dissolution and precipitation. The results showed that the lower DP of cellulosic materials caused an increase of degradability for the NaOH pretreated samples compared to untreated samples. The NaOH pretreatment was more effective for shorter chain cellulose.

Input-output models were constructed to describe the economic impacts of timber product outputs in Ohio and its three timber market regions – the Northeast, West, and Southeast – for 2012. Impact Analysis for PLANning was used to describe these impacts in terms of employment, output, and value added based on 1) the total value of outputs delivered to market by each region’s logging sector and 2) a per-unit change in the regionalized delivered value of one million board feet (MMBF) of hardwood sawtimber. Direct impacts of timber products were greatest in the Northeast (for output and value added) and Southeast (for employment). The total economic impacts of timber products in Ohio were 2,880 employees, $287 million in output, and $147 million in value added. The per-unit impact results were more varied due to regional differences in economies and timber price determinants. Employment and output economic impacts per MMBF were both highest in the Southeast. The employment levels directly and indirectly associated with each MMBF in the West were higher than the Northeast. Value added per MMBF was highest in the Northeast across impacts.

In this paper, a portable scanner to determine the 3D shape of logs was evaluated and compared with the measurement result of a computer tomography scanner. Focus was on the accuracy of the shape geometry representation. The objective is to find a feasible method to use for future data collection in Mozambique in order to build up a database of logs of tropical species for sawing simulations. The method chosen here was a 3D phase-shift laser scanner. Two logs, a birch log with bark, and a Scots pine log without bark were scanned, resulting in 450 cross sectional “images” of the pine log and 300 of the birch log. The areas of each point cloud cross section were calculated and compared to that of the corresponding computer tomography cross section. The average area difference between the two methods was 2.23% and 3.73%, with standard deviations of 1.54 and 0.91, for the Scots pine and birch logs, respectively. The differences in results between the two logs are discussed and had mainly to do with presence of bark and mantle surface evenness. Results show that the shape measurements derived from these methods were well correlated, which indicates the applicability of a 3D phase-shift laser scanning technology for gathering log data.

World energy demand is expected to continue increasing in the coming years. This situation has created a worldwide pressure for the development of alternative fuel and energy sources, pursuing a more environmentally friendly usage of biofuels. The EU has the target of generating 20% of its energy consumption from renewable sources by 2020. Member States have different individual targets to meet this overall target. Meanwhile in the United States, there are about 750 million acres [300 million hectares] of forestland, with slightly more than two-thirds classified as timberland or land capable of producing 20 cubic feet per acre [1.4 m3 per hectare] annually of roundwood. Given these circumstances, this research aimed to understand the U.S. opportunities to export woody biomass based on the targets that the European Union has imposed to its Member States. The data collected allowed several scenario developments by identifying the possible EU’s biomass deficits and U.S.’s capacity to supply the gaps. Considering the physical availability, the U.S. would be able to satisfy between 42 and 48% depending on the energy efficiency scenario. Nevertheless, when considering reasonable biomass prices, only a small portion of the EU demand could be covered by the U.S.

Biochars form recalcitrant carbon and increase water and nutrient retention in soils; however, the magnitude is contingent upon production conditions and thermo-chemical conversion processes. Herein we aim at (i) characterizing switchgrass (Panicum virgatum L.)-biochar morphology, (ii) estimating water-holding capacity under increasing ratios of char: soil; and, (iii) determining nutrient profile variation as a function of pyrolysis conversion methodologies (i.e. continuous, auger pyrolysis system versus batch pyrolysis systems) for terminal use as a soil amendment. Auger system chars produced at 600 °C had the greatest lignin portion by weight among the biochars produced from the continuous system. On the other hand, a batch pyrolysis system (400 °C – 3h) yielded biochar with 73.10% lignin (12 fold increases), indicating higher recalcitrance, whereas lower production temperatures (400 °C) yielded greater hemicellulose (i.e. greater mineralization promoting substrate). Under both pyrolysis methods, increasing biochar soil application rates resulted in linear decreases in bulk density (g cm^-3). Increases in auger-char (400 °C) applications increased soil water-holding capacities; however, application rates of >2 Mt ha^-1 are required. Pyrolysis batch chars did not influence water-holding abilities (P>0.05). Biochar macro and micronutrients increased, as the pyrolysis temperature increased in the auger system from 400 to 600 °C, and the residence time increased in the batch pyrolysis system from 1 to 3 h. Conversely, nitrogen levels tended to decrease under the two previously mentioned conditions. Consequently, not all chars are inherently equal, in that varying operation systems, residence times, and production conditions greatly affect uses as a soil amendment and overall rate of efficacy.

Moso bamboo (Phyllostachys edulis) is an important source of lignocellulosic materials because of its fast growth, its vegetative propagation, and its easy harvesting. The pretreatment of bamboo with dilute sulfuric acid and the effects on its chemical components and enzymatic hydrolysis were studied, in addition to the fibrous structural properties of pretreated residues by scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared (FTIR) spectroscopy. The results showed that dilute sulfuric acid pretreatment primarily hydrolyzed hemicelluloses and resulted in enhanced cellulose and lignin content in the pretreated solids. The maximum yield of hemicellulose recovery was 81.42% when pretreated with 1.00% sulfuric acid at 150 °C for 30 min, and the enzymatic hydrolysis yield was 79.45% when hydrolyzed for 72 h with an enzyme loading of cellulase 40 FPU/g of cellulose. Under these conditions, the overall sugar yield was 83.36% (cellulose and hemicellulose), with a total of 67.11 g fermentable sugars from 100 g dry bamboo. The results indicated that Moso bamboo underwent considerable changes in its chemical composition and physical properties after acid pretreatment, such as the removal of hemicellulose and lignin, an increase in specific surface area and pore volume, and exposure of internal structure, which enhances the enzymatic hydrolysis of Moso bamboo.

The effect of different physico-chemical treatments used in the isolation process of aloe vera (AV) rind nanofibers on the tensile properties of the nanofiber films were studied to understand the root of the low strength values of these films. In the first stage of the investigation, ground AV rind was subjected to different chemical treatments before mechanical defibrillation. In the second stage, cuticle present in the AV rind was removed before subjecting them to chemical treatment. Nanofiber films were prepared using these defibrillated AV rind pulp fibers, and tensile properties were measured to examine the effect of chemical treatments and the raw material characteristics on the nanofibrillation process. The results showed that tensile values were not affected significantly with the chemical treatments; however, the thick cuticle coated on AV rind had a significant effect on the tensile strength and Young’s modulus of the nanofibre films. The maximum tensile strength and Young’s modulus (234.5 MPa and 12.6 GPa) of AV rind nanofibre films without cuticle were very high compared to the nanofibre films with the cuticle (tensile strength of about 110 MPa and Young’s modulus of 10 GPa). The study also found that mild chemical treatments were sufficient to isolate nanofibres from AV rind. The morphological analyses illustrated that the isolated AV rind nanofibers had a diameter size smaller than 20 nm and a high aspect ratio of approximately 1000 to 1500 or larger.

The production rate and yield of ethanol was markedly increased when water hyacinth, pretreated with microwave-assisted dilute acid, was fermented with acclimatized yeasts through simultaneous saccharification and fermentation. Water hyacinth hydrolyzate microwaved with 1% (v/v) dilute sulfuric acid was fermented with the acclimatized mixed yeasts Pichia stipitis and Pachysolen tannophilus at a volume ratio of 1:1. The highest ethanol yield was 0.22 g/g (raw biomass of water hyacinth), which was 76.3% of the theoretical ethanol yield. A maximum ethanol production rate of 0.19 g/(L·h) was obtained after 24 h.