Effect of diffusivity on gas-side mass transfer coefficient

✍ Scribed by A. Tamir; J.C. Merchuk

• Publisher: Elsevier Science
• Year: 1978
• Tongue: English
• Weight: 375 KB
• Volume: 33
• Category: Article
• ISSN: 0009-2509
• DOI: 10.1016/0009-2509(78)85119-7

✦ Synopsis

Abstrac-Expenments conducted In a stirred cell on evaporation of pure bqulds Into various tamer gases yield that the gas-wde NaSS transfer coefficient, 4, IS proportIonal to the bmary dfiusmty, D, ramed to the power 0 684 t-2/3) Ih'TRODUCTION The obJectrve of the present study IS to detemme the exponent n in the relatlonshlp &SD" (1) resultmg from basic models for mass transfer Thus IS achieved from evaporation expenments of pure hqulds into various gases 111 a stirred cell This techmque assures that the gas side resistance 1s the controlhng factor The major advantage of the stured cell over previous devices is its known mterfaclal area for mass transfer Consequently, the true gas-side mass transfer coefficient k. can be determmed rather than an overall coefficient &,a, so that It IS possible to study directly the effect of D on k, According to the film-model, n = 1 The penetration model and the random surface renewal model suggested by Danckwerts predict that n = 0 5, whereas the filmpenetration model[l] predicts that the exponent n may vary from 0 5 to 1 Expertmental results for n m the relationship k,aaD" (21