This article was downloaded by: [Univ Du Quebec A Chicoutimi] On: 19 March 2014, At: 11:17 Publisher: Taylor & Francis Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House, 37-41 Mortimer Street, London W1T 3JH, UK Journal of Wood Chemistry and Technology Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/lwct20 Estimation of Jack Pine, Black Spruce, and Balsam Fir Proportions in Wood Chips Dr. André Pichette a , François-Xavier Garneau a , Guy Collin a , France-Ida Jean a & Bernard Riedl b a LASEVE , Université du Québec à Chicoutimi , Chicoutimi, Québec, Canada b Faculté de Foresterie et de Géomatique , CERSIM , Université Laval , Ste-Foy, Québec, Canada Published online: 16 Feb 2007. To cite this article: Dr. André Pichette , François-Xavier Garneau , Guy Collin , France-Ida Jean & Bernard Riedl (2003) Estimation of Jack Pine, Black Spruce, and Balsam Fir Proportions in Wood Chips, Journal of Wood Chemistry and Technology, 23:2, 131-140, DOI: 10.1081/WCT-120021921 To link to this article: http://dx.doi.org/10.1081/WCT-120021921 PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content. This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http:// www.tandfonline.com/page/terms-and-conditions
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This article was downloaded by: [Univ Du Quebec A Chicoutimi]On: 19 March 2014, At: 11:17Publisher: Taylor & FrancisInforma Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House,37-41 Mortimer Street, London W1T 3JH, UK
Journal of Wood Chemistry and TechnologyPublication details, including instructions for authors and subscription information:http://www.tandfonline.com/loi/lwct20
Estimation of Jack Pine, Black Spruce, and Balsam FirProportions in Wood ChipsDr. André Pichette a , François-Xavier Garneau a , Guy Collin a , France-Ida Jean a & BernardRiedl ba LASEVE , Université du Québec à Chicoutimi , Chicoutimi, Québec, Canadab Faculté de Foresterie et de Géomatique , CERSIM , Université Laval , Ste-Foy, Québec,CanadaPublished online: 16 Feb 2007.
To cite this article: Dr. André Pichette , François-Xavier Garneau , Guy Collin , France-Ida Jean & Bernard Riedl (2003)Estimation of Jack Pine, Black Spruce, and Balsam Fir Proportions in Wood Chips, Journal of Wood Chemistry and Technology,23:2, 131-140, DOI: 10.1081/WCT-120021921
To link to this article: http://dx.doi.org/10.1081/WCT-120021921
PLEASE SCROLL DOWN FOR ARTICLE
Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) containedin the publications on our platform. However, Taylor & Francis, our agents, and our licensors make norepresentations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of theContent. Any opinions and views expressed in this publication are the opinions and views of the authors, andare not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon andshould be independently verified with primary sources of information. Taylor and Francis shall not be liable forany losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoeveror howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use ofthe Content.
This article may be used for research, teaching, and private study purposes. Any substantial or systematicreproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in anyform to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http://www.tandfonline.com/page/terms-and-conditions
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INTRODUCTION
Black spruce (Picea mariana), balsam fir (Abies balsamea), and jackpine (Pinus banksiana) are three of the softwoods most utilized in pulpand paper manufacture in eastern Canada.[1] Pulp and paper industriesdo not favor incorporation of jack pine in the pulp since it can lead toincreased power consumption in paper making as well as to paper yellow-ing.[1–3] For these reasons, pulp and paper firms wish to limit the presenceof jack pine in the pulp and favor its use as timber. In practice, papermills obtain their wood chips from sawmills as a mixture of the threeaforementioned species in variable proportions. With process optimiza-tion and paper quality control in mind, it is important for the mills to beaware of these proportions. Several methods have been studied to differ-entiate the wood of conifers, and in certain cases attempts have made toapply such methods to sorting lumber.[4–8] However, these methods havenot been applied to a mixture of wood chips. To the best of our knowl-edge, only one other analytical approach has been reported by Finnishresearchers[2] on the evaluation of pine (Pinus silvestris) and spruce (Piceaabies) proportions in mechanical pulping. The aim of this work was todevelop and validate an analytical approach which would eventually leadto an evaluation of the relative amounts of each species in a wood chipsample through the use of species-specific molecular markers.
EXPERIMENTAL
Wood
Twelve jack pines, twelve balsam firs, and ten black spruces, growingin the Saguenay-Lac-St-Jean region of Quebec, were felled in August1995. The age of the trees varied from 24 to 114 years for black spruce,55 to 102 years for jack pine, and 35 to 122 years for balsam fir. Wooddisks (1 cm) were cut from debarked logs (first two meters of the stem) ofeach tree and the sapwood and heartwood were carefully separated usingchisels. Pieces of heartwood and sapwood were dried overnight at roomtemperature and ground with an industrial grinder equipped with a 2mmsieve. Equivalent amounts of sapwood from each log of a particularspecies were mixed together in order to minimize individual variations.Heartwood mixtures were prepared in the same fashion. Since thecomposition of wood chips from sawmills is about 75% sapwood and25% heartwood, the mixtures used for analyzis contained the sameproportions. Calibration curves were obtained using ten ternary mixtures
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with different amount of the three wood species. The percentage of blackspruce in the mixtures varied from 60 to 95% and those of balsam fir andjack pine were between 0 and 25%, since in eastern Canada chips arecomposed mainly of black spruce (generally more than 65%).
Bark
Bark of three black spruces, three balsam firs, and three jack pineswere took, extracted the same way as wood and analyzed by GC.
Extraction
Samples of the wood mixture (50 g) were extracted with 295mL ofhexane and 5mL of a solution of an internal standard (1.5 g tetradecane in500mL of hexane). We choose to work with hexane because it is a goodsolvent to extract the volatiles products of low polarity, which can then beanalyzed easily by GC. The mixture of wood and solvent was slowlystirred for 10min at room temperature using a mixer, and an aliquot of20mL was taken from the supernatant solution, dried over anhydrousMgSO4, filtered, and evaporated at room temperature to 0.5mL.
Gas Chromatographic (GC) Analyses of Wood Extracts
Gas chromatographic analyzes were performed on a Hewlett-Packard 5890 gas chromatograph equipped with a polar Supelcowaxcolumn (30m� 0.25mm with 0.25 mm film) and an apolar DB-5column (30m� 0.25mm with 0.25 mm film) and a split-splitless injectionport (split mode). The temperature program was 60�C for 2min, then2�C/min to 140�C, then 1�C/min to 190�C, then 2�C/min to 210�C,and this temperature was held constant for 28min. The specificmarkers were identified by their Kovats indices[9] on both columns andby spectroscopic analyzes.[10]
Impact of Aging on Chemical Markers Content
in Wood Chips
A large sample (6–7m3) of chips produced by a sawmill was storedon the grounds of a pulp and paper mill for a 2 month period (from early
MARCEL DEKKER, INC. • 270 MADISON AVENUE • NEW YORK, NY 10016
September to early November). During this period the temperaturevaried from 15 to �5�C. Four samples were withdrawn, three of theseduring the first month and one at the end of the two month period.Samples were extracted and the amount of markers measured.
RESULTS AND DISCUSSION
Chemical Marker Selection
Previous work[10] on the chemical differences between these soft-woods enabled identification of natural products specific to balsam firand jack pine but not to black spruce. Chemical marker selection wasdone in such a way as to satisfy certain criteria. First, an extractive isspecies specific, i.e., is a marker, if it is found only in the extract of thisspecies, or, if it is abundant in the extract of one species and at very lowconcentrations in the others. Second, the concentration of the marker hasto be sufficient to exclude sensitivity problems in the analytical method.Chemical extractives selected as markers were juvabione[11–12] found inbalsam fir wood, and pimaral[10] found in jack pine wood. The gas chro-matographic analyzes of the bark of the three species showed that thesemarkers are not present in the bark, only in the wood. Figure 1 showsthree typical chromatograms of extracts for the three softwood species.Tables 1 and 2 show the percentage composition of the markers in theheartwood and the sapwood of these conifers. Juvabione is quite abun-dant in balsam fir extracts and is totally absent in the extracts of the twoother species. In the case of jack pine, the diterpene marker is less abun-dant than juvabione in balsam fir, but still present in adequate quantitiesto be used as a marker. It is also present in black spruce, but in tracequantities only. Thus, although we have not identified a species specificmarker for black spruce, under the present conditions of extraction andanalyzis, the relative proportion of black spruce in the chip pile can stillbe evaluated, not directly, but by taking into account the known propor-tions of fir and pine. The presence in the sample of a sizable proportion ofa species other than these three softwoods, such as a hardwood, wouldinvalidate this approach.
Calibration Curves
The amounts of jack pine and balsam fir markers in extracts ofternary mixtures were measured by gas chromatography. The amount
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of each marker was quantified as the ratio of the chromatographic peakarea of the marker relative to that of an internal standard (IS). Eachextract was injected at least twice, and mean values were used to createcalibration curves. Chromatograms of repeated injections of the sameternary mixture extract were quite reproducible (% variation of each
marker
marker
BALSAM FIR
JACK PINE
BLACK SPRUCE
0 10 20 30 40 80 90 100 110 120
Figure 1. Schematic gas capillary chromatograms of the extracts of wood of
MARCEL DEKKER, INC. • 270 MADISON AVENUE • NEW YORK, NY 10016
peak was less than 5%). Calibration curves show good linearity, as can beseen in Figs. 2 and 3. It should be noted that the calibration curve for jackpine (Fig. 3) does not pass through the origin because the jack pinemarker is present in trace quantities in the wood of black spruce. Thesecalibration curves permit evaluation of the proportions of jack pine andbalsam fir in samples of wood chips simply by doing an extraction withhexane and analyzing the extract by GC. As an example of the precisionof our analytical method, a wood sample, prepared in our laboratory bymixing a predetermined proportion of the three conifers, was extractedwith hexane. Gas chromatographic analyzis showed the presence of thebalsam fir marker (juvabione area/IS area¼ 0.07) and the jack pinemarker (pimaral area/IS area¼ 0.023). Using Figs. 2 and 3, interpolationgave the results shown in Table 3. The uncertainties of the measurementsshown in Table 3 were determined with the standard error of theestimate[13] at a confidence level of 95% (twice the standard error ofthe estimated value). As seen in Table 3, percentages measured for jackpine and balsam fir are not far removed from the actual values.
Also, the accuracy of the measurement of the relative proportionsof the species is very dependent on the proportions of heartwood andsapwood, which are estimated at 25:75 by certain industries. If this ratio
Table 1. Percentage of markers present in the heartwood of three species of
conifers.
Retention indicesComposition (%)
Identification on DB-5 column Jack pine Black spruce Balsam fir
Juvabione 2017 0 0 55.44
Pimaral 2158 6.43 0.74 0
Table 2. Percentage of markers present in the sapwood of three species of
conifers.
Retention indicesComposition (%)
Identification on DB-5 column Jack pine Black spruce Balsam fir
MARCEL DEKKER, INC. • 270 MADISON AVENUE • NEW YORK, NY 10016
changes, the reliability will decrease rapidly as the quantity of markers inheartwood and sapwood are different. Furthermore, the use of a limitednumber of trees in this study, twelve jack pines, twelve balsam firs, and tenblack spruces, to minimize the effect of individual variations within asingle species, does not guarantee that the sample used is a representativeof the species. To minimize further the level of this uncertainty, it wouldhave been necessary to use a much larger sample of individual trees forestablishing the calibration curves; this would be a daunting task consid-ering the number of trees that may be required. Analysis of a large numberof trees to know the individual variation in the chemical composition,especially the markers, is a work we plan to do later to complete our study.
Impact of Aging on Wood Chips
Normally, as many industries told us, wood chips do not stay out-side the mill more than 3 weeks. In spite of this, we wanted to study theeffect of aging (temperature, humidity, etc.) on the chemical markerconcentration in industrial wood chips. As shown in Table 4, themarker concentration in the wood material was only weakly influencedby aging: only a decrease in the amount of balsam fir marker wasobserved after two weeks. This suggests that, with normal storingconditions, species specific markers are sufficiently stable to be usedfor analytical purposes. It would be interesting to see if the effectof aging is more important during the summer period when thetemperature vary from 15 to 30�C.
CONCLUSION
As has been shown in this work at the laboratory level, it is possibleto evaluate the proportions of jack pine and balsam fir in a mixture of
MARCEL DEKKER, INC. • 270 MADISON AVENUE • NEW YORK, NY 10016
wood chips, as well as black spruce by difference, by taking advantage ofthe presence of species specific natural products in the wood. Calibrationcurves were established using mixtures of wood chips of different propor-tions of the three conifers and in a ratio of heartwood to sapwood of25 to 75, similar to that produced by sawmills. The accuracy of themethod depends on the ratio of heartwood to sapwood. Finally, chipaging when the temperature varied from �5 to 15�C did not have alarge influence on the concentrations of markers. Further work is inprogress to improve the accuracy and precision of the method byexamining peak ratios and by sampling a larger number of trees.
ACKNOWLEDGMENTS
The authors are grateful to Helene Gagnon for helping with GCwork. The financial support of the Consortium de recherches sur laforet boreale commerciale, Universite du Quebec a Chicoutimi, theUniversite Laval and the ministere des Ressources naturelles duQuebec is gratefully acknowledged. A. Pichette thanks the FCAR fundof Quebec for a postgraduate scholarship.
REFERENCES
1. Law, K.N.; Valade, J.L. Status of the utilisation of jack pinein the pulp and paper industry. Can. J. For. Res. 1994, 24,2078–2084.
2. Sundberg, K.; Orsa, F.; Wikstrom, B.; Holmbom, B.; Ekman, R.Assessment of pine and spruce wood proportions in pulp productionby the analyzis of resin acids. Paperi Ja Puu-Paper and Timber 1997,79 (5), 327–329.
MARCEL DEKKER, INC. • 270 MADISON AVENUE • NEW YORK, NY 10016
7. Nault, J.R.; Manville, J.F. Differentiation of some canadianconiferous woods by combined diffuse and specular reflectancefourier transform infrared spectrometry. Wood Fiber Sci. 1992,24 (4), 424–431.
8. Brunner, M.; Eugster, R.; Trenka, E.; Bergamin-Strotz, L. FT-NIRspectroscopy and wood identification. Holzforschung 1996, 50,130–134.
9. Kovats, E. Gas chromatographic characterization of organic sub-stances in the retention index system. Adv. Chromatogr. 1965, 1,229–247.
10. Pichette, A.; Garneau, F.-X.; Jean, F.-I.; Riedl, B.; Girard, M.Chemical differences between the wood extracts of jack pine,black spruce, and balsam fir from eastern canada. J. Wood Chem.Technol. 1998, 18, 427–438.
11. Manville, J.F. Juvabione and its analogs. Juvabione and dehydro-juvabione isolated from the whole wood of Abies balsamea, have theR,R Stereoconfigurations, not the R,S. Can. J. Chem. 1975, 53,1579–1585.
12. Bowers, W.S.; Fales, H.M.; Thompson, M.J.; Uebel, E.C. Juvenilehormone: identification of an active compound from balsam fir.Science 1966, 154, 1020–1021.
13. Sokal, R.R.; Rohlf, F.J. Biometry, 2nd Ed.; W.H. Freeman andCompany: New York, 1981; 454–560.
