Integrated reaction-separation system

In the following, a number of integrated reaction-separation systems wiU be discussed, with emphasis on the application of polymeric membranes. As a result, the systems discussed will be Hmited to relatively low temperatures, typically below 120°C. In Section 13.2, appHcations of membranes in chemical synthesis will be described. Subsequently, in Section 13.3 various examples of membrane bioreactors will be discussed. 

These studies prove that the C02-expanded Hquid concept is also appHcable to ILs and can lead to versatile, integrated reaction-separation systems. 

FI Hydride Generation with Integrated Reaction-separation Systems... 

The integrated reaction-separation system was tested for arsenic, selenium and antimony and was shown to provide improved tolerance to interferences due to better conditions in kinetic discrimination, but further refinements appear to be necessary to improve the sample throughput and sensitivities. 

Figure 2.1 — Variants of integrated reaction, separation and detection in continuous-flow analytical systems. (1) Reaction/separation. (2) Reaction/detec-tion. (3) Separation/detection. (4) Reaction/separation/detection.

The outline of this chapter is as follows First, some basic wave phenomena for separation, as well as integrated reaction separation processes, are illustrated. Afterwards, a simple mathematical model is introduced, which applies to a large class of separation as well as integrated reaction separation processes. In the limit of reaction equilibrium the model represents a system of quasilinear first-order partial differential equations. For the prediction of wave solutions of such systems an almost complete theory exists [33, 34, 38], which is summarized in a second step. Subsequently, application of this theory to different integrated reaction separation processes is illustrated. The emphasis is placed on reactive distillation and reactive chromatography, but applications to other reaction separation processes are also... 

The theory presented above also applies to other integrated reaction separation processes which fall into the class of systems illustrated in Fig. 5.1. Typical examples are sorption-enhanced gas phase reactions (as described in Chapter 7) or membrane reactors (as described in Chapter 12). 

The OHLM systems, integrating reaction, separation, and concentration functions in one equipment (bioreactor), find a great interest of researchers in the last few years. A bioreactor combines the use of specific biocatalyst for the desired chemical reactions, and repeatedly or continuously application of it under very specific conditions. Such techniques were termed as hybrid membrane reactors. In biotechnology and pharmacology, these applications are termed as hybrid membrane bioreactors or simply bioreactors (see Table 13.11). Experimental setup of the bioreactor system is shown schematically in Figure 13.17. 

Fig. l2 An integrated reaction-separation-detection FI system for cold vapour determination of mercuiy by AAS. [21,56] A, 6, plexiglas blocks held together by screws (not shown) C, reaction coil D, acidified sample and carrier, E, borohydride reductant G, grooved channel for flow of reaction mixture F, waste flow M. microporous PTFE membrane 1, incident light path J, slot for gas diffusion into light path. 

When it comes to combination with a reaction or conversion, membranes have mainly found application in a sequential mode, i.e. reaction followed by separation. In this chapter, we wiU focus on the integration of conversion and separation in so-caUed membrane reactors. As the separation function of the membrane can be used in various modes of operation, this leads to a broad variety of process options. In the past few years, several review papers have emerged, usually covering parts of this huge research field [1-5]. The general advantages of membrane reactors as compared to sequential reaction-separation systems are ... 

Figure 1 Layouts of a microfluidic chip combining mixing and reaction zones (capillary system connecting resen/oirs 1-5) with an integrated electrophoretic separation system (reservoirs 6 and 7).

Gopatakrishnan, M., Ramdoss, P., and EI-Halwagi, M. (1996). Integrated design of reaction and separation systems for waste minimization. AIChE Annu. Meet., Chicago. 

The feasibility of constructing a miniaturised system including reaction, separation and detection units integrated directly onto the EC-CE microchip device has also been shown and approximates the concept of total analysis system . Furthermore, the low cost of the EC detection in connection with new polymer material can bring a real disposable device. 

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