Effect of pressure on viscosity of naphthalene, phenanthrene and impregnation pitches

✍ Scribed by J.A. Roetling; J.J. Gebhardt; F.G. Rouse

• Publisher: Elsevier Science
• Year: 1987
• Tongue: English
• Weight: 781 KB
• Volume: 25
• Category: Article
• ISSN: 0008-6223
• DOI: 10.1016/0008-6223(87)90121-7

✦ Synopsis

Viscosities of Allied 15V coal tar pitch and Ashland A-240 petroleum pitch were determined at pressures up to 101 and 67 MPa, respectively, at temperatures up to 608 and 588 K, respectively, using a falling needle viscometer. Measurements were also made on naphthalene and phenanthrene up to 101 MPa. Activation energies required to initiate shear flow under pressure were calculated from the data using the Eyring model and found to increase with pressure and to be 50%-100% greater for A-240 than for 15V. The viscosity of A-240 decreases more rapidly with increasing temperature so that at about 625 K, the effect of increasing pressure on viscosity is minimal. Activation energies for naphthalene and phenanthrene decrease with increasing pressure, suggesting increased ,alignment of these planar molecules and reduced resistance to initiation of flow.