Solubilite de liquides non-électrolytes dans des solution aqueuses d'électrolytes

✍ Scribed by Mirtha Susana Bidner; Miguel de Santiago

• Book ID: 103005316
• Publisher: Elsevier Science
• Year: 1971
• Tongue: English
• Weight: 252 KB
• Volume: 26
• Category: Article
• ISSN: 0009-2509
• DOI: 10.1016/0009-2509(71)80070-2

✦ Synopsis

Shorter Communications

// h = 0.55 would be low by about a factor of four. Such an error could conceivably have a large influence on the analysis of a large-scale catalytic reactor such as a fixed bed.

Therefore the suitability of approximate methods for predicting overall rates for one set of parameters and surface conditions is not a good indicator of their suitability "for predicting derivatives. The failure of an asymptotic method to approximate derivatives well means of course that the method will provide less satisfactory estimates of overall rates under different conditions at the external catalyst surface.

Shell

Development Company Emeryville, Calif. 94608, U.S.A. J. E. BAILEYt NOTATION A frequency factor in rate constant c reactant concentration c* reference reactant concentration C reactant De effective diffusivity of C h Thiele modulus AH heat of reaction k rate constant ke effective thermal conductivity L catalyst slab half-thickness q defined by Eq. (21) r local reaction rate R overall reaction rate Ro gas law constant T temperature T* reference temperature xt dimensionless concentration x2 dimensionless temperature y extent of reaction y extent of reaction at equilibrium z distance from catalyst centerline G reek symbols /3 defined by Eq. (5.3) y defined by Eq. (5.4) X adjoint variable e dimensionless distance from catalyst centedine Subscripts s evaluated at external catalyst surface 0 reaction fimited regime oo diffusion limited regime