Chromatographic batch reactor

Chromatographic batch reactors are employed to prepare instable reagents on the laboratory scale (Coca et al., 1993) and for the production of fine chemicals. These applications include the racemic resolution of amino acid esters (Kalbe et al., 1989), acid-catalyzed sucrose inversion (Lauer, 1980), production of dextran (Zafar and Barker, 1988) and saccharification of starch to maltose (Sarmidi and Barker, 1993a). Sardin et al. (1993) employed batch chromatographic reactors for different esterification reactions such as the esterification of acetic acid with ethanol and the transesterification of methylacetate. Falk and Seidel-Morgenstern (2002) have investigated the hydrolysis of methyl formate. 

A common modeling approach for chromatographic batch reactors is the equilibrium-transport dispersive model (Chapter 6.2.4.1). Therefore, only the equations for this approach are discussed here. The differential mass balance (Fig. 8.6) takes into account axial dispersion as well as mass transfer between fluid and both solid phases. 

Villermaux (1981) has investigated the applicability of the chromatographic batch reactor for isomerizations. The simulation studies show that the conversion within the integrated batch reactor can not exceed the conversion in a fixed bed reactor without separation. Therefore, the integrated batch reactor does not offer any advantages for reactions of type A B compared with a sequential process. 

A reaction of type A B + C is used in Figure 5.10 to explain the principles of chromatographic batch reactors. In the given example, the reactant A has... 

All reactions involving lactic acids were performed in 300 mL Parr Autoclave batch reactor. All reagents, including the resin catalyst, were charged into the reactor and heated up to the desired reaction temperature. Stirring was commenced once the desired temperature was reached this was noted as zero reaction time. Reaction sample were withdrawn periodically over the course of reaction and analysed for ester, water and alcohol using a Varian 3700 gas chromatograph with a thermal conductivity detector (TCD) and a stainless steel... 

As with the catalytic distillation reactor, the chromatographic reactor functions as a multistage reactor. The chromatographic reactor is essentially a batch reactor, and we need to adapt this configuration into a continuous process to develop a large-scale and economic process. 

ATR-IR spectroscopy can be used as a spy inside a reactor for on-line monitoring and control of a reaction. The emphasis in this kind of application of ATR spectroscopy is on the detection of reactants and products in the bulk fluid phase. Such applications benefit from the excellent time resolution of FTIR instruments compared to other analytical tools, such as chromatographs. The method can be used in investigations of kinetics of reactions in batch reactors instrumentation has been developed and even commercialized that allows measurements at elevated temperatures and pressures. 

Very recently, Morrison, Rinker, and Corcoran320 reported on similar experiments performed with NO in the range of parts per million for the temperature range 17-37°C in a constant volume batch reactor. They obtained their data by gas-chromatographic determination... 

In contrast to chromatographic batch and annular reactors, at most two pure products can be withdrawn. To obtain an optimal process, sections II and III have to be carefully designed with respect to total conversion. After the start up period the TMBR reaches steady state. 

After selecting the chromatographic system the operation mode of the batch reactor has to be chosen. High productivities require a high throughput. Therefore, pulsed operation is used (Fig. 8.8). Reactants are supposed to be injected as a rectangle pulse of period tcic le and duration tinj. These parameters are strongly affected by the reaction kinetics, reaction stoichiometry and adsorption isotherm. 

The reaction was carried out in both batch and distillation reactor. 0.5 g catalyst (0.2-0.3 mm grain) was used for the catalyst activity test in a stainless batch reactor with 6 1 ratio of methanol to propylene carbonate. After the reaction proceeded for 2h at 160°C under constant stirring, the reactor was cooled down to room temperature and the products were then analyzed on a gas chromatograph with a TCD after centrifugal separation from the catalyst. 

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