Title: Wood Science and Technology

Title: Wood Science and Technology

ISO Abbreviated Title: Wood Sci. Technol.

JCR Abbreviated Title: Wood Sci Technol

ISSN: 0043-7719

Issues/Year: 4

Journal Country/Territory: United States

Language: English

Publisher: Springer Verlag, Springer-Verlag Heidelberg

Publisher Address: 175 Fifth Ave, New York, NY 10010

Subject Categories:

Forestry: Impact Factor 0.291, 26/29 (2000)

Materials Science, Paper & Wood: Impact Factor 0.291, 11/20 (2000)

? Carrasco, F. and Roy, C. (1992), Kinetic study of dilute-acid prehydrolysis of xylan-containing biomass. Wood Science and Technology, 26 (3), 189-208.

Full Text: 1992\Woo Sci Tec26, 189.pdf

Abstract: With the current interest in chemicals production from biomass and in view of the emerging pulping processes, the hydrolysis of lignocellulosics is being considered as a promising industrial approach. Since hemicellulose is more readily hydrolyzed than cellulose, most processes include a prehydrolysis step to remove pentosans prior to the main hydrolysis of cellulose to glucose. However, the mechanism of solid-phase acid-catalyzed hydrolysis has not been elucidated and it is impossible to predict the extent of reaction a priori. Having the goal to design reactors, engineers need empirical rate equations. A series of kinetic data available in the literature have been compiled and different kinetic empirical models were analyzed in order to simulate the dilute-acid prehydrolysis of xylan-containing materials. The objective of this paper is to provide profiles of xylan removal and xylose production as a function of a few process variables such as: preheating time, heating rate, acid concentration, reaction temperature and reaction time. Moreover, the influence of biomass species as well as the type of reactor were studied to understand the different solubilization profiles obtained. Other variables such as biomass concentration and particle size were also analyzed. The cellulose dissolved during the prehydrolytic stage was calculated to determine the prehydrolysis selectivity.

Keywords: Sulfuric-Acid, Hydrolysis, Xylose, Saccharification, Economics, Residues

? Hernandez, R.E. (1993), Influence of moisture sorption history on the swelling of sugar maple wood and some tropical hardwoods. Wood Science and Technology, 27 (5), 337-345.

Full Text: 1993\Woo Sci Tec27, 337.pdf

Abstract: Samples of nine tropical hardwoods from Peru and sugar maple wood from QuebeC were selected to perform moisture sorption tests associated with swelling tests at 25°C. The results demonstrate that, for a given equilibrium moisture content, tangential and radial dimensions, and hence the volume of wood, are greater after desorption than after adsorption. The importance of these differences, so-called second-order effects of moisture sorption, varied with the species and with the direction of swelling. These effects are proportionally greater in the tangential direction of wood than in its radial axis. Finally, two types of samples showed similar swellings for three equilibrium moisture contents.

? Seki, K., Saito, N. and Aoyama, M. (1997), Removal of heavy metal ions from solutions by coniferous barks. Wood Science and Technology, 31 (6), 441-447.

Full Text: 1997\Woo Sci Tec31, 441.pdf

Abstract: The abilities of 15 coniferous barks for removing toxic heavy metal ions were investigated. The barks considerably varied in the adsorption ability to each metal ion. of the barks tested, high adsorption ability for heavy metal ions was found in Picea abies (Norway spruce). Equilibrium experiments using P. jezoensis (Yezo spruce) bark showed that the adsorption of Cd²⁺ was greatly affected by the pH of solution and the initial Cd²⁺ concentration in solution. The adsorption of Cd²⁺ by P. jezoensis bark followed Freundlich isotherm in the concentration range 10-330 mgCd²⁺/L. The continuous column experiments using P. jezoensis bark indicated that the packing had retained 10.1-14.2 mg Cd²⁺/g adsorbent until the column broke through.

Keywords: Adsorbent, Adsorption, Bark, Freundlich Isotherm, Heavy Metal, Heavy Metal Ions, Heavy-Metal, Leaves, Metal, Metal Ions, pH, Uranium

Jorge, F.S., Santos, T.M., de Jesus, J.P. and Banks, W.B. (1999), Reactions between Cr(VI) and wood and its model compounds. Part 2: Characterisation of the reaction products by elemental analysis, magnetic susceptibility and FTIR. Wood Science and Technology, 33 (6), 501-517.

Full Text: W\Woo Sci Tec33, 501.pdf

Abstract: Hexavalent chromium solutions at two pH levels (about 1.3 and 7.8) were reacted with wood, gum ghatti, lignin, cellulose and simple model compounds representing wood chemical structures (guaiacol, vanillin, vanillyl alcohol, homovanillyl alcohol, methyl-(beta-D-glucoside, and methyl-beta-cellobioside). Reaction products were isolated and characterised by elemental analysis, magnetic susceptibility, and Fourier-transform infrared spectroscopy (FTIR). Data suggest that all the chromium present in the reaction products is in its trivalent oxidation state. After reduction reactions, wood and macromolecular substances generally fixed a relatively low level of chromium, which contrasts with the high level in the products isolated from the reaction with the model compounds. It appears that the reaction of the simple model compounds with Cr(VI) did not produce complex adducts of Cr(III) but inorganic substances, of the hydrated chromium oxide type. Therefore, under the experimental conditions applied, simple model compounds do not seem to behave chemically as wood or as the macromolecular substances investigated. Hence, their significance as model compounds must be object of further assessment. An exception is the product from the reaction of vanillyl alcohol and K₂CrO₄ aq. This contains a relatively small amount of chromium and its FTIR spectrum presents rather well defined bands indicating reaction of the phenolic hydroxyl and secondary alcohol groups. This system must be worthy of further investigation as a model for lignin.

Keywords: Cca-Treated Wood, Chromated Copper Arsenate, Southern Pine, Spectroscopic Analysis, Chromic-Acid, Preservatives, Performance, Durability, Mechanism, Stability

Naderi, N. and Hernández, R.E. (2000), Influence of wood planing on the second-order effects of moisture sorption in sugar maple. Wood Science and Technology, 33 (3), 215-222.

Full Text: W\Woo Sci Tec33, 215.pdf

Abstract: Summary Two types of machines, a conventional planer, and a fixed-knife pressure-bar planer were used to prepare matched specimens of sugar maple wood. After adsorption and desorption, both experiments at 21 °C, the EMC, swelling in all principal directions as well as compliance coefficient in radial compression were measured. Two specimen sizes were used for these expe-riments. For a given equilibrium moisture content, tangential and radial dimensions were greater after desorption than after adsorption, as previously described. When equilibrium was reached by gaining moisture, the wood was stiffer in radial compression compared to when the equilibrium was reached after losing moisture. The magnitude of this phenomenon, second-order effects of moisture sorption, was slightly affected by the type of planing. These effects on swelling were greater for large specimens prepared by conventional planing compared to fixed-knife pressure-bar planing. Small specimens showed similar magnitudes of this phenomenon with both planing methods. No differences between planing methods were found for the radial compliance coefficient measured on either specimen size. Therefore, the second-order effects of moisture sorption appeared to be a bulk phenomenon and not restricted to the superficial layers of wood.

Aoyama, M., Tsuda, M., Cho, N.S. and Doi, S. (2000), Adsorption of trivalent chromium from dilute solution by conifer leaves. Wood Science and Technology, 34 (1), 55-63.

Full Text: W\Woo Sci Tec34, 55.pdf

Abstract: Chromium(III), Cr(III) adsorption capacities of the leaves of 34 conifer species were examined. Among these, Ginkgo biloba, Taxus cuspidata, Cephalotaxus harringtonia var. nana, and Taxodiaceae and Cupressaceaes showed large capacities to adsorb Cr(III). The adsorption capacities of conifer leaves for Cr(III) (3.12-5.09 mgCr g^-1 adsorbent) compared favorably with those of commercial activated carbons (1.23-2.75 mgg^-1). Factors affecting Cr(III) adsorption were studied using G. biloba leaves. The factors included solution pH, contact time, temperature, and the initial concentration of Cr(III). The amount of Cr(III) adsorbed on the adsorbent increased steadily with increasing pH in a pH range from 2 to 5, with increasing contact time, and with increasing temperature ranging 20 to 40°C. The Cr(III) adsorption was also affected by the initial concentration of Cr(III) in the solution. A linear relationship was observed between the amount of Cr(III) adsorbed and the equilibrium concentration of Cr(III) in the solution when graphed logarithmically. The maximum capacity of G. biloba leaves was 27.5 mgCr g^-1 adsorbent by column experiments.

Keywords: Heavy-Metal Ions, Activated Carbon, Aqueous-Solutions, Removal, Uranium, Barks

Marchetti, V., Clement, A., Gerardin, P. and Loubinoux, B. (2000), Synthesis and use of esterified sawdusts bearing carboxyl group for removal of cadmium(II) from water. Wood Science and Technology, 34 (2), 167-173.

Full Text: W\Woo Sci Tec34, 167.pdf

Abstract: Improvement of the reaction of succinic anhydride with wood meal was studied in order to prepare low cost materials for the removal of heavy metals. Without solvent, the use of 1 equivalent of pyridine or triethylamine, succinic anhydride was necessary to obtain high grafting efficiencies at 80°C. In the presence of small quantities of 1,2-dichloroethane as swelling agent, only 0.1 equivalent of catalyst was needed to obtain satisfactory results. Three more or less modified sawdusts were used after activation with NaHCO₃ for the removal of cadmium(II) from water. Metal binding capacity was directly connected with the acid value estimated by titration and can reach 200 mg, g. Strongly modified sawdust showed a cadmium binding capacity lower than expected because of diester formation

Keywords: Activation, Adsorption, Cadmium, Heavy Metals, Heavy-Metal Ions, Removal, Sawdust, Wood, Woods

Aoyama, M. and Tsuda, M. (2000), Removal of Cr(VI) from aqueous solutions by larch bark. Wood Science and Technology, 35 (5), 425-434.

Full Text: W\Woo Sci Tec35, 425.pdf

Abstract: The ability of larch (Larix leptolepis Gold.) bark to remove Cr(VI) from dilute aqueous solutions was investigated. The research parameters included the solution pH, contact time, temperature and initial concentration of Cr(VI) in solution. of the parameters studied, the solution pH was found to be the most crucial. The Cr(VI) removal decreased steadily throughout the pH range studied (pH 2-6), while the Cr adsorption peaked at pH 3. Because the chemical reduction of Cr(VI) to trivalent state occurred to lesser extents even in strong acidic media, the Cr(VI) removal was mainly governed by physico-chemical adsorption. The positive value of the heat adsorption (DeltaH(0)) indicates the endothermic nature of the Cr(VI) adsorption. The relatively slow rate and irreversible nature of the adsorption as well as the order of the magnitude of the heat adsorption value suggest that the adsorption is of a chemical type. The adsorption data obtained from the equilibrium experiments were well fitted to both the Langmuir and Freundlich isotherms.

Keywords: Acid, Adsorption, Bark, Binding, Chromium, Coniferous Leaves, Heavy-Metal Ions, Langmuir, Peanut Skins, Recovery, Removal, Waste, Water

Garrote, G. and Parajó, J.C. (2002), Non-isothermal autohydrolysis of Eucalyptus wood. Wood Science and Technology, 36 (2), 111-123.

Full Text: W\Woo Sci Tec36, 111.pdf

Abstract: Non-isothermal autohydrolysis treatments of Eucalyptus globulus wood were carried out in batch reactors in order to assess the kinetics of hemicellulose degradation, as well as the effects caused on cellulose and lignin. Experiments were carried out at a liquor to wood ratio of 8 g, g, and two heating profiles were explored. The maximum temperature considered was 224°C, and the longest reaction time was 0.94 h. The experimental variables considered were solid residue yield, solid residue composition and composition of liquors. Up to 90.4% of the initial xylan was removed in treatments, which also caused some delignification (up to 13.8% of the initial lignin was removed), whereas cellulose was almost quantitatively retained in solid phase. The conversion of xylan into xylooligomers, with further hydrolysis to xylose and decomposition of this sugar into furfural was assessed by means of a kinetic model based on sequential, first order reactions involving kinetic coefficients with Arrhenius-type dependence on temperature.

Keywords: Acid Prehydrolysis, Biomass, Extraction, Fractionation, Hardwood Prehydrolysis, Hydrolysis, Kinetics, Lignin, Lignocellulosics, Pretreatment, Water, Wheat-Straw, Wood

Arévalo, R. and Hernández, R.E. (2004), Influence of moisture sorption on the tangential compression strength of Mahogany wood (Swietenia macrophylla King). Wood Science and Technology, 37 (5), 419-425.

Full Text: W\Woo Sci Tec37, 419.pdf

Abstract: Moisture sorption tests and compression tangential tests at 25degreesC were carried out on specimens of mahogany (Swietenia macrophylla King) wood from Peru. The tests were performed over seven adsorption and five desorption moisture conditions, and differences in strength between adsorption and desorption curves at a given equilibrium moisture content were evaluated. The results showed that second-order effects in mahogany wood were not discernible in either the tangential compliance coefficient or for the stress at the proportional limit in tangential compression.

Keywords: Sugar Maple Wood, Hardwoods

Low, K.S., Lee, C.K. and Mak, S.M. (2004), Sorption of copper and lead by citric acid modified wood. Wood Science and Technology, 38 (8), 629-640.

Full Text: W\Woo Sci Tec38, 629.pdf

Abstract: The sorption characteristics of citric acid modified wood to remove copper and lead ions from aqueous solution under batch conditions have been investigated. Sorption was pH dependent with increasing uptake at higher pH values. The kinetics of sorption for both ions was rapid with 90% sorption taking place within the first 60 min regardless of its initial concentration. Sorption can be explained by a second-order kinetics model from which the rate constant, the equilibrium sorption capacity and the initial rate were calculated. From these parameters,. the predictive models for Cu and Pb sorbed (q(t)) in time t and at an initial concentration (C-o) are given by q(t) = C(o)i[0.31 C-o-2.29 + (0.04C(o) + 5.19)t] and q(t) = C(o)dagger/[0.06C(o) - 6.59 + (0.001C(o) + 4.48)r] for Cu and Pb, respectively. Using these models the predicted and experimental uptakes of Cu and Pb were compared and discussed. Maximum sorption capacities of modified wood under present experimental conditions were 23.70 and 82.64 mg/g for Cu and Pb, respectively. However. for untreated wood the corresponding values were 2.56 and 7.71 mg/g indicating a tenfold increase in sorption upon citric, acid modification. Ethylene diamine tetraacetic acid and nitrilotriacetic acid complexed with both ions render sorption less favorably. However-salicylic acid had little influence. In a binary system, Pb ions Were more favorably sorbed than Cu Ions which could be due to the larger ionic radius of the former ions.

Keywords: Ion-Exchange Properties, Metal-Ions, Quaternized Wood, Aqueous-Solution, Heavy-Metals, Rice Hulls, Removal, Biosorption, Adsorption, Adsorbents

? Rao, P.S., Reddy, K.V.N.S., Kalyani, S. and Krishnaiah, A. (2007), Comparative sorption of copper and nickel from aqueous solutions by natural neem (Azadirachta indica) sawdust and acid treated sawdust. Wood Science and Technology, 41 (5), 427-442.

Full Text: 2007\Woo Sci Tec41, 427.pdf

Abstract: This study investigates the potential use of neem (Azadirachta indica) sawdust treated with hydrochloric acid for the removal of copper(II) and nickel(II) ions from wastewater. The effects of different system variables, viz, adsorbent dosage, initial metal ion concentration, pH and contact time were studied. The results showed that as the amount of the adsorbent was increased, the percentage of metal ion removal increased accordingly. Optimum pH value for metal adsorption is determined as 5.0 for Cu(II) and 4.0 for Ni(II) ions. Maximum metal is sequestered in 150 min for Cu(II) and 180 min for Ni(II) after the beginning of every experiment. Similar experiments were carried out with acid treated sawdust to compare the results. The adsorption of metal ions followed a first order rate equation. Both Freundlich and Langmuir adsorption models are suitable for describing the sorption of Cu(II) and Ni(II) on the two forms of sawdust. Furthermore, the natural organic matter (neem sawdust) is characterized by FTIR spectra and surface area analysis. At optimal conditions the maximum adsorption capacity is found to be 48.3 and 286 mg/g for Cu(II) and 31.5 and 74.1 mg/g for Ni(II) in natural and acid treated forms, respectively.

Keywords: Acid, Adsorbent, Adsorbent Dosage, Adsorption, Adsorption Capacity, Adsorption Models, Analysis, Aqueous Solutions, Azadirachta Indica, Barks, Capacity, Cassava Waste, Concentration, Contact Time, Copper, Cu, Cu(II), Dosage, Dye, Effects, Experiment, Experiments, First Order, Freundlich, FTIR, FTIR Spectra, Heavy-Metal Ions, Hydrochloric Acid, Ion, Ions, Kinetics, Langmuir, Langmuir Adsorption, Leaves, Matter, Metal, Metal Adsorption, Metal Ion, Metal Ion Concentration, Metal Ion Removal, Metal Ions, Models, Natural, Natural Organic Matter, Ni, Nickel, Optimal Conditions, Order, Organic, Organic Matter, pH, Potential, Rate, Rate Equation, Removal, Sawdust, Solutions, Sorption, Spectra, Surface, Surface Area, Time, Treated Sawdust, Value, Wastewater

? Gong, R.M., Ni, S.J., Zhao, J.J. and Li, N. (2009), Epichlorohydrin and aspartic acid incorporated into sawdust and application as sorbent for methylene blue. Wood Science and Technology, 43 (3-4), 183-193.

Full Text: 2009\Woo Sci Tec43, 183.pdf

Abstract: In this paper, a new cation exchanger is prepared by activating sawdust with epichlorohydrin, followed by coupling the epoxy-activated sawdust with aspartic acid. The sawdust cation exchanger (SCE) was investigated for its methylene blue (MB) removal capacity from aqueous solution. The removal experiments were performed under various conditions such as different initial pH, SCE dosage, dye concentration, ionic strength, and contact time in a batch system. The highest sorption capacity of MB was obtained beyond pH 4. The 2.0 g/l or more of SCE could remove above 95% of MB from 250 mg/l of dye solution. Increasing the ionic strength of the solution caused decline of MB sorption. The sorption isotherm conformed well to the Langmuir model. The sorption process could be described by the pseudo-second-order kinetic model.

Keywords: Agricultural Waste, Aqueous-Solutions, Dye Adsorption, Equilibrium, Malachite Green, Reactive Dyes, Removal, Rice Husk, Sorption, Textile Waste-Water

? Mun, S.P., Ku, C.S. and Kim, J.P. (2010), Adsorption of metal and uranyl ions onto amidoximated Pinus densiflora bark. Wood Science and Technology, 44 (2), 283-299.

Full Text: 2010\Woo Sci Tec44, 283.pdf

Abstract: Pine (Pinus densiflora) bark was chemically modified by grafting with acrylonitrile (AN) through Fenton reaction and conversion of the cyano group to an amidoxime group by reaction with hydroxylamine. Treatments of pine bark with 160 mM H₂O₂ at 40AºC yielded similar to 70% grafting in 6-h reaction. After alkali hydrolysis of amidoximated pine bark (AOPB), its adsorption capacity (q (e)) for copper ions was largely increased from 0.5 to 1.8 mmol/g. Adsorption of the hydrolyzed AOPB (HAOPB) followed the pseudo-second-order kinetic model. Among the metal ions tested, the order of adsorption capacity (q (e)) predicted by the kinetic model at equilibrium time was Hg²⁺ > UO₂²⁺> Cd²⁺ > Cu²⁺ > Zn²⁺ > N²⁺. The adsorption process was pH-dependent, and the adsorption equilibrium was observed in the pH range of 6-7 for all the metal ions. Even though pine bark is a good adsorbent for Hg²⁺ and UO₂²⁺ ions, it had a poor affinity for the other ions tested. It was obviously found that HAOPB had very high adsorption abilities for heavy metal and uranyl ions.

Keywords: Acrylonitrile, Adsorbent, Adsorption, Adsorption Capacity, Adsorption Equilibrium, Antioxidant Properties, Aqueous-Solutions, Capacity, Cd²⁺, Copper, Cu²⁺, Equilibrium, Fenton, Graft-Polymerization, Grafting, H₂O₂, Heavy Metal, Heavy-Metal, Hydrolysis, Ions, Kinetic, Kinetic Model, Metal, Metal Ions, Methylene-Blue, Model, Modified, Ni²⁺, pH, pH-Dependent, Pine Bark, Pseudo Second Order, Pseudo-Second-Order, Pseudo-Second-Order Kinetic Model, Radiata Bark, Range, Reaction, Removal, Sawdust, Sorption, Time, Treatments, Uranyl Ions, Water, Zn²⁺

? Rafatullah, M., Sulaiman, O., Hashim, R. and Ahmad, A. (2012), Removal of cadmium(II) from aqueous solutions by adsorption using meranti wood. Wood Science and Technology, 46 (1-3), 221-241.

Full Text: 2012\Woo Sci Tec46, 221.pdf

Abstract: Meranti wood, an inexpensive material, has been utilized as an adsorbent for the removal of cadmium(II) from aqueous solutions. Various physico-chemical parameters such as equilibrium contact time, solution pH, initial metal ion concentration, and adsorbent dosage level were studied. Langmuir, Freundlich, Dubinin-Radushkevich (D-R) and Temkin isotherms were used to analyze the equilibrium data at different temperatures. The experimental data fitted well with the Langmuir adsorption isotherm, indicating the monolayer adsorption of the cadmium(II). The monolayer adsorption capacity of meranti wood for cadmium(II) was found to be 175.43, 163.93 and 153.84 mg/g at 30, 40, and 50AºC, respectively. The thermodynamics of cadmium(II) adsorption on meranti wood indicates its spontaneous and exothermic nature. Kinetic studies showed that the adsorption followed a pseudo-second-order kinetic model. The results indicated that the meranti wood could be an alternative for more costly adsorbents used for cadmium(II) removal.

Keywords: Adsorbent, Adsorbents, Adsorption, Biosorption, Cadmium, Cd(II), Concentration, Dubinin-Radushkevich, Equilibrium, Freundlich, Heavy-Metal Ions, Isotherm, Isotherms, Kinetic, Kinetic Studies, Kinetics, Langmuir, Metal Ion, Pb(II) Ions, pH, Removal, Rice Husk, Sawdust, Sorption, Thermodynamics, Waste-Water