Sorptive and Catalytic Properties of Partially Sulfonated Resins

Abstract

Sulfonic poly(styrene-co-divinylbenzene) ion-exchange resins are commonly employed as supported acid catalysts or as selective sorbents in a number of different applications. Using the reaction of acetic acid and methanol to form methyl acetate and water as a model system, the competitive sorption behavior of the corresponding nonreactive binary pairs was studied for macroporous, highly cross-linked resins of different acid loading. It was found that a reduction of the acid loading decreases the resins' selectivity toward the sorption of water and increases its affinity toward less polar species, e.g., methyl acetate. To describe the sorption behavior a phase equilibrium model based on the Flory-Huggins theory of polymer swelling was developed, taking into account the hydration of the acid sites upon the sorption of water. The ability of the model to represent the competitive sorption behavior as a function of the resin's acid loading has been demonstrated by comparison with various sets of experimental equilibrium data. Finally, initial work to characterize the catalytic performance for different degrees of sulfonation is presented, and conclusions toward the application of these resins as stationary phases for reactive chromatography are drawn.

Absorption of water/methanol binary system on ion‐exchange resins

“…The data from Song et al (1998) have not been considered in our comparison, because, the authors have not furnished all the necessary parameters for evaluating the effectively absorbed amounts of water and methanol. However, while the very low differences observed between our data and data from Pöpken et al (2000) can be explained with the difficulty of completely drying the resin, data reported by Lode et al (2004) are too much different for such explanation. The explanation could be related with the more drastic pre-treatment of the resin made by the authors.…”

“…A comparison of the experimental data for the absorption of the binary mixture water-methanol on the acid exchange resin. (Song et al, 1998;Pöpken et al, 2000;Lode et al, 2004). It is important, first of all, to point out that our data are strictly comparable with the ones obtained by Pöpken et al (2000), while, data by Lode et al (2004) are very different, in particular for low water concentrations.…”

“…As it can be seen, our model well reproduce both our experimental data and data by Pöpken et al (2000) in all the concentrations field. The same approach has also been applied to the data taken from Lode et al (2004). A poor agreement is obtained in this case.…”

“…Unfortunately, data available in the literature about this binary system, collected on the same resin (Amberlyst 15) are not in agreement and the models adopted by the different authors for interpreting their data seem not appropriate. A complex phase-partition model, not easily transferable to the subsequent step of kinetic investigation, has been developed by Mazzotti et al (1997);and Lode et al (2004) describing binary systems water-ethanol and water-methanol on Amberlyst 15, at 25…”

Síntese e sulfonação de resinas poliméricas macroporosas e avaliação na remoção de petróleo e de anilina em água

“…Outra aplicação para as resinas sulfonadas refere-se à sua utilização como suporte catalítico [16][17][18][19] . Na literatura, no entanto, não foi encontrado um estudo detalhado da utilização de resinas sulfonadas no tratamento da água oleosa.…”