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Wood sawdust

Its appeal Hes in the fact that synthesis gas can be produced from trash, municipal sewage, scrap wood, sawdust, newsprint, or other waste. The early work of Fischer and Tropsch on methanol synthesis showed that ethanol could be obtained in the process (165) and that by certain modifications the proportion of ethanol in the product could be increased (166). The Hterature concerning this method is extensive (167—176). The conditions that favor ethanol formation are 125—175°C and 1.42 MPa (14 atm) in the presence of reduction catalysts such as powdered iron. [Pg.408]

Aqueous alkaline extraction of wood was employed by Poumarede and Figuier48 in 1846 for the removal of a substance called wood gum. Similar very crude xylan or hemicellulose preparations were made by other workers of the early period. Extractions were made not only from wood sawdust, but from annual plant materials such as wheat straw, corn cob, etc.49-66... [Pg.288]

It has been reported that thermoplastic properties can be imparted to wood by modification of wood particles with fatty acid chlorides in a dinitrogen tetroxide -dimethylformamide - pyridine mixture (Funakoshi etal., 1979 Shiraishi etal, 1979, 1983). A method has also been developed for the modification of wood sawdust without the addition of organic solvents (Thiebaud and Borredon, 1995), and the thermal properties of such modified wood determined (Thiebaud etal, 1997). [Pg.85]

Bark, trimmings, split wood, sawdust, planer shavings, sander dust... [Pg.48]

Additional sources included arils, balsams, barks, beans, berries, branches, buds, bulbs, calyxes, capsules, calkms. cones, flowering tops, fronds, gums, hips, husks, kernels, needles, nuts, peels, pits, pulps, rhizomes, rind, roots, seeds, shoots, stalks, sitgnias. siolons thalli. rwigs. wood, and wood sawdust, as well as some entire plants. [Pg.645]

In all reactions, wood of white fir Abies concolor) has been used. For the alkaline nitrobenzene reactions, extractive-free —20+40 mesh heart-wood sawdust containing 28.0% Klason lignin was used. Sequential extraction of the original sawdust with alcohol-benzene, 95% ethanol, and hot water gave extractives amounting to 4.9, 0.5, and 1.2%, respectively. In the other oxidation reactions, nominal 5 -in. wood chips, commonly used in pulping procedures, were employed. The mixed sap wood-heart-wood chips contained 26.5% Klason lignin and sequential extractives of 3.3, 0.5, and 3.2%, respectively. [Pg.195]

Raw materials for fiberboard manufacture come from several sources including whole wood, sawdust and mill residues, waste paper, agricultural wastes, and plant tissue other than woody stems. Additives usually enable attaining the desired properties but whole wood reduced to virgin fiberboard pulp often can be converted to board of impressive properties with little or no additives. High lignin content of virgin fiberboard pulps is usually cited as the source of this superiority. [Pg.202]

Mechanical pulping has higher yields but lower-strength pulps when compared to full chemical pulps. Improvements are constantly being made, and considerable gains have been made in adapting different types of wood and different forms of wood (sawdust versus chips) to mechanical pulping via advanced process control techniques. [Pg.453]

Woody Aromatic characteristic of dry wood. Sawdust, wood chips, popsicle sticks, or peanut oil heated to 190°C for 30 min... [Pg.461]

T. Kotoyori, Critical Ignition Temperatures of Wood Sawdusts, Proceedings of the E International Symposium on Fire Safety Science, Gaithersburg, Maryland, 1985, Hemisphere Publishing Corporation, Washington D.C., 463-471 (1985). [Pg.62]

Hemati, M. Laguerie, C. (1988). Determination of the kinetics of the wood sawdust Steam-gasification of charcoal in a thermobalance, Entropie, No. 142, pp. 29-40. [Pg.45]

Mixed wood sawdust, 1-3 mm vapour residence time 1.0 s. [Pg.1276]

A group of methods to obtain lignin are known as organosolv procedures. They consist of an extraction of wood sawdust with an alcohol (such as ethanol) and some acid (5% HCI) in stronger conditions (boiling under reflux) followed by the reprecipitation of lignin from the extract. [Pg.328]

A wide range of organic products is suitable as feed.stocks for the manufacture of activated carbon. Wood, sawdust, peat, coconut shells and even olive stones are the preferred uncarbonized feedstocks. Of the (already) carbonized feedstocks coal, low temperature lignite coke, charcoal and coke from acid sludges (e.g. from the manufacture of lubricants) are utilized. The properties of activated carbon are very much influenced by the type of feedstock utilized. [Pg.528]

U.S. Pat. No. 5,474,722 [38] describes a composite material 20-80% of which is a cellulosic material (ground wood, sawdust, wood flour, rice hulls, etc.) and polyethylene. [Pg.82]

U.S. Pat. No. 6,939,496 [43] discloses a system and method of extruding plastic-cellulose fiber composite material, comprising 60-95% by weight of a thermoplastic polymer such as polypropylene, polyethylene, and PVC, 20-30% of cellulose fiber obtained from such materials as wood sawdust (60 mesh particle size), hemp, flax, straw and wheat, and a binding agent mixed with the filler. [Pg.82]

Antal, M.J., Jr. and X. Xu, "Hydrogen Production by the Total, Catalytic, Supercritical Steam Reforming of Wood Sawdust", 216th American Chemical Society National Meeting, Boston, August 23, 1998. [Pg.62]

The availability of both the cellulose and hemicellulose in untreated wood sawdust is low and for conifers such as lodgepole pine, eastern hemlock, and balsam fir is essentially zero. [Pg.265]

Xylan is a wood gum which is found in the bark of trees. It can be obtained by extracting pine-wood sawdust or straw with dilute sodium hydroxide, and precipitating the alkaline solution with alcohol and hydrochloric acid. Xylan is a porous mass which dissolves in hot water to form a solution that becomes opalescent on cooling. It yields xylose when hydrolyzed by acids when distilled with acids, the xylose formed is converted into furfurol. [Pg.356]

Ofomaja AE. Kinetic study and sorption mechanism of methylene blue and methyl violet onto Mansonia (Mansonia Altissima) wood sawdust. Chem Eng J 2008 143(1-... [Pg.72]

This paper presents an outline of the main ideas and results illustrating the fusion like behaviour of biomass pyrolysis. The ablative pyrolysis rate of wood rods applied on a hot spinning disk or on a stationnary heated surface is studied. The observations are quite similar to those made in the same conditions with rods of true melting solids (ice, paraffin,. ..) in agreement with a theoretical approach. The "fusion temperature of wood is found close to 739 K in agreement with a limited number of experiments of wood sawdust fast pyrolysis in a hot cyclone reactor. The results show also that in most of the experimental devices, the direct measurement of wood pyrolysis reaction rate constant is impossible above about 800 K. [Pg.66]


See other pages where Wood sawdust is mentioned: [Pg.162]    [Pg.51]    [Pg.458]    [Pg.162]    [Pg.450]    [Pg.449]    [Pg.634]    [Pg.115]    [Pg.634]    [Pg.1002]    [Pg.1126]    [Pg.1277]    [Pg.385]    [Pg.424]    [Pg.528]    [Pg.87]    [Pg.698]    [Pg.147]    [Pg.677]    [Pg.294]    [Pg.298]    [Pg.299]    [Pg.544]    [Pg.567]    [Pg.129]   
See also in sourсe #XX -- [ Pg.227 ]

See also in sourсe #XX -- [ Pg.139 ]




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