Amberlyst special

An important feature of packed DCRs is the need to pack the catalyst in a special way to ensure good flow, mass transfer, and contact characteristics. An example of this is the use of an ion-exchange resin catalyst (Amberlyst 15) in methyl tertiary butyl ether (MTBE) manufacture. The bed consists of bags made in the form of a cloth belt with narrow pockets sewn across it (Figure 25.7). The pockets are filled with catalyst granules, and the belt is twisted into a helical form, referred to as a bale (see Smith, 1980, for details). Clearly, each pocket represents a closely packed bed of unconsolidated particles, and the pocket and the individual particles exhibit, respectively, their own distinctive macro- and microdiflfusional features. This is broadly similar to the particle-pellet model of a catalyst pellet (see Chapter 7) but with distinctly different pellet behavior. Therefore, it is necessary to define an overall effectiveness factor which takes this unique feature into account. An attempt to do this was recently reported (Xu... 

In the series of heterogeneous acid catalysts, we tested specially prepared aluminum, titanium, zirconium, and sihcon oxides phosphoric acid on sihca gel subjected to high temperature treatment and polymeric sulfoacids (commercially accessible Amberlyst, NaCbn, KU-2). The conversion of glycerol was 23-55% with a double excess of acetone. The catalyst must have medium acidity for the process to occur... 

Khajavi, Jansen, and Kapteijn (2010) used an R2-type ESU-PVMR for the esterification of acetic acid with ethanol and acetic acid with 1-butanol. In these two cases, a mbular hydroxy sodalite (SOD) membrane was used. The reactions were performed using equimolar mixtures of acetic acid and organic alcohol at 363 K. Amberlyst 15 was chosen as solid acid catalyst. The special feamre of the SOD membrane was the absolute selectivity toward water and the relative high stability under the reaction conditions. In fact, the water selectivity in these experiments was above 1,000,000 and... 

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