RHEOLOGICAL CHARACTERIZATION OF PYROLYTIC WOOD DERIVED OILS: EXISTENCE OF A COMPENSATION EFFECT
1988; Taylor & Francis; Volume: 71; Issue: 1 Linguagem: Inglês
10.1080/00986448808940421
ISSN1563-5201
AutoresJoël Leroy, L. Choplin, Serge Kaliaguine,
Tópico(s)Petroleum Processing and Analysis
ResumoAbstract Detailed rheological study was made for sixteen pyrolytic wood derived oils provided by different laboratories and obtained from a wide range of liquefaction processes. Molecular characterization of these oils has been performed through gel permeation chromatography (GPC) and intrinsic viscosity [η] measurements. All pyrolytic wood derived oils exhibit an essentially Newtonian behavior in the range of shear rate examined (10-1 to 103s-1). The variation of viscosity with temperature follows an Arrhenius-type relationship. GPC chromatograms and [ η] measurements have shown the existence of a Mark-Houwink relationship between [ η] and molecular weights of the pyrolytic oils with a Mark-Houwink exponent of the order of 0.58 when tetrahydrofuran (THF) is used as solvent. Therefore the pyrolytic oils despite the diversity of the liquefaction processes all belong to a same family. Moreover, a compensation effect has been found. Because of the Newtonian character of these oils, the compensation effect allows the determination of the temperature dependence of viscosity from only one measurement of viscosity at a given temperature KEYWORDS: Pyrolytic wood oilsGel permeation chromatographyRheology Compensation effect
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