ISSN:
0001-1541
Keywords:
Chemistry
;
Chemical Engineering
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Process Engineering, Biotechnology, Nutrition Technology
Notes:
Kinetics of the dehydration of t-butyl alcohol to isobutylene were measured with a semibatch reactor containing liquid reactant and suspended particles of cation exchange resin catalyst [sulfonated copolymer of styrene and divinylbenzene (DVB)]. Effects on rate were determined for variations in temperature (58 to 76°C.), reactant water mole fraction (0.0005 to 0.10), and catalyst pacticle diameter (77 to 620 μ) and crosslinking (2 to 12% DVB).Nearly anhydrous t-butyl alcohol failed to penetrate the shrunken network of the polymer. Reaction ebgan only on particle peripheries, and product water penetrated the gel network and s welled it to allow penetration of the alcohol. Rate consequently increased to a maximum (about 0.5 moles/min. equivalent of catalyst —SO3H groups at 76°C.) and then decreased as water competed with reactant fro catalytic sites. A spherical catalyst particle is modeled as a shrinking cetrol core, free of reactant and water, and a swollen shell in which concent rations are independent of position and time. The model fits reaction rate and separate particle swelling data for 80 μ particles of catalyst containing 12% DVB, but it is increasingly inadequate for larger particles and catalysts of lower DVB contents.
Additional Material:
9 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/aic.690180212
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