Mathew Leitch

Hydrolytic degradation of alkaline lignin in hot-compressed water and ethanol.

Alkaline lignin of a very high molecular weight was successfully degraded into oligomers in a hot-compressed water-ethanol medium with NaOH as the catalyst and phenol as the capping agent at 220-300 degrees C. Under the optimal reaction conditions, i.e., 260 degrees C, 1 h, with the lignin/phenol ratio of 1:1 (w/w), almost complete degradation was achieved, producing <1% solid residue and negligible gas products. The obtained degraded lignin had a number-average molecular weight M(n) and weight-average molecular weight M(w) of 450 and 1000 g/mol respectively, significantly lower than the M(n) and M(w) of 10,000 and 60,000 g/mol of the original lignin. A higher temperature and a longer reaction time favoured phenol combination, but increased the formation of solid residue due to the condensation reactions of the degradation intermediates/products. The degraded lignin products were soluble in organic solvents (such as THF), and were characterized by HPLC/GPC, IR and NMR. A possible mechanism for lignin hydrolytic degradation was also proposed in this study.

Catalytic conversion of glucose to 5-hydroxymethyl furfural using inexpensive co-catalysts and solvents

Efficient conversion of glucose to 5-hydroxymethyl furfural (5-HMF), a platform chemical for fuels and materials, was achieved using CrCl(2) or CrCl(3) as the catalysts with inexpensive co-catalysts and solvents including halide salts in dimethyl sulfoxide (DMSO) and several ionic liquids. 5-HMF (54.8%) yield was achieved with the CrCl(2)/tetraethyl ammonium chloride system at mild reaction conditions (120°C and 1h). The 5-HMF formation reaction was found to be faster in ionic liquids than in the DMSO system. Effects of water in the reaction system, chromium valence and reaction temperature on the conversion of glucose into 5-HMF were discussed in this work.

Liquefaction of cornstalk in hot-compressed phenol–water medium to phenolic feedstock for the synthesis of phenol–formaldehyde resin

Cornstalk powders were effectively liquefied in a hot-compressed phenol-water medium (1:4 wt/wt). The optimum liquefaction temperature was around 350 degrees C, where the liquid yield attained a maximum at about 70 wt%. The addition of sodium carbonate showed negligible effect over the Liquefaction product yields. When liquefied in phenol-water medium, essentially no phenol was combined with the liquid products, and the cornstalk-derived bio-oils were partially degraded monomeric and oligomeric products with a broad molecular distribution. Resol type bio-based phenol formaldehyde resins were readily synthesized from the cornstalk-derived bio-oils catalyzed by sodium hydroxide.

An application of data envelopment analysis to investigate the efficiency of lumber industry in northwestern Ontario, Canada

This study aims at exploring the technical efficiency of lumber industry in northwestern Ontario, Canada using data envelopment analysis (DEA). The DEA model analyzes relative technical efficiency of lumber mills with disproportionate inputs and outputs by dividing the 10-year time series data, for inputs and outputs of 24 lumber mills, over two periods (1999–2003 and 2004–2008). Four inputs, namely, material (log volume), labour (man-hours), two types of energy (hog-fuel and electricity), and one output (lumber volume) are used in this study. The trend analysis shows an annual reduction of 10%, 13% and 13% for lumber output, log consumption (input) and number of employees, respectively, during the period 1999–2008. The results from DEA with two scenarios with energy inputs and without energy inputs, for the two periods are found to be mixed and interesting. While some mills have improved their performance in terms of best use of available scarce inputs in the second period, some have shown negative per cent change in efficiency. In the with energy input and the without energy input scenario, some of the mills show a reduction in efficiency in the second period from the first period, with the highest estimated reductions of −13.9% and −47.6%, respectively. A possible explanation for these negative performances of mills in the latter period is the decline in production in the second period compared to the first period, where these mills were not able to adjust their inputs (mostly labour) as proportional lay-offs might not have been possible. These results provide policy makers and industry stakeholders with an improved understanding of the trends of efficiency and employment as well as reallocation opportunities of future inputs in order to increase benefits from this sector.

Production of lignosulfonate in NSSC-based biorefinery.

The spent liquor (SL) of a neutral sulfite semichemical (NSSC) pulping process contains a considerable amount of lignocelluloses and is treated in wastewater systems. The lignocelluloses, however, can be used for producing value‐added products if they are isolated from the SL. In this article, solvent treatment (mixing acetone, ethanol, or isopropyl with SL) was used as a method for isolating lignosulfonate from SL. The maximum lignosulfonate removal was obtained via mixing isopropyl alcohol with SL at the weight ratio of 20/80, room temperature, and 5.7 pH. The results also showed that the molecular weight and anionic charge density of the precipitates were in the range of 5,000–70,000 g/mol and 0.2–1.8 meq/g, respectively. Based on these results, a process was proposed for isolating lignosulfonate from SL and converting the NSSC process to an NSSC‐based biorefinery.

Comparative analysis of the production technologies of logging, sawmill, pulp and paper, and veneer and plywood industries in Ontario

Technological growth in production and efficient utilization of input factors are the two biggest contributors to total factor productivity (TFP). TFP of the four major forest industries (logging, pulp and paper, sawmill, and veneer and plywood industries) of Ontario are compared by analyzing their production structures using duality theory in production and costs. The study uses annual data of output and four inputs — labour, capital, energy and materials — from 1967 to 2003. Different restrictions on the translog cost function are applied to each industry to determine the cost function that best describes each industry’s technology, which is further used to estimate Morishima elasticities of substitution, own-price and cross-price elasticities, rate of technological change, and TFP. The production structure of sawmill and veneer and plywood industries is found to be linear homogeneous and homothetic, and that of logging and pulp and paper industries is non-homothetic. Further, Hicks neutral technologica...

Quality assessment of cut-to-length logging residues for bioenergy production in Northwestern Ontario

The use of the cut-to-length (CTL) forest harvesting method has been increasing in eastern Canada due to its versatility and its potential for lower environmental impact. In this study we assess the quality of CTL logging residues for bioenergy production in Northwestern Ontario. The qualities assessed were moisture content, gross calorific value, and ash content. Analysis of variance was used to determine whether duration of storage, logging residues species class, or diameter class had a significant effect on each of these qualities. Moisture content values ranged from 10.6% to 28.9% green-weight basis. Drying seasons, logging residues species class, and diameter class all had a significant effect on moisture content. The gross calorific values of residues ranged from 19.5 to 22.8 MJ/kg. Drying seasons and species class did not have a significant effect on gross calorific value, while the diameter class of logging residues did. The ash content of the CTL logging residues ranged from 0.4% to 4.2%. Ash content showed a decreasing trend with increase in number of drying seasons. Drying seasons and diameter class had a significant effect on ash content, but species class did not show any significance. CTL logging residues left in the forest continued to increase in quality from 1 to 3 drying seasons after harvest. From the transportation and combustion viewpoints, moisture content is reduced to an acceptable level after one drying season.

Integrating operational planning decisions throughout the forest products industry supply chain under supply and demand uncertainty

ABSTRACT In the face of both supply and demand uncertainty, the forest products industry needs advanced supply chain management models that can significantly improve their competitiveness in global markets. This paper aims to provide a decision support tool for integrating operational planning decisions with inventory management of all agents in a multi-product forest industry supply chain under supply and demand uncertainty. A pulp mill is considered as the nodal agent and an integrated simulation-based optimization model is developed, which minimizes the cost of the entire supply chain for different customer satisfaction levels, while material and information flow both upstream and downstream of the pulp mill. The incorporation of a merchandizing yard helps in managing risks associated with supply and demand uncertainty in the forest products industry supply chain. There is a net annual cost saving of

Lignin–carbohydrate complexes: properties, applications, analyses, and methods of extraction: a review

17.4 million by including a merchandizing yard in the supply chain. However, there is an increase in handling, holding and transportation costs. Comparing the shortage cost to the handling, holding and transportation costs, it is observed that as long as the shortage cost is above

Optimizing Wood Utilization Based on Whole Tree Inherent Property Maps

6.80 per m3, it is viable to keep the merchandizing yard. The merchandizing yard not only absorbs supply shocks for the pulp mill, but also reduces the safety stocks on the downstream side. This integrated supply chain model can be used for operational planning decisions that minimize overall cost for any agent in the supply chain.