Multi-channel micro reactor

Reactor 1 [R 1] Reactor Module with Different Multi-channel Micro Reactors... 

Investigations with the modular multi-channel [28,98] and silicon chip [19, 56-62] micro reactors demonstrate that by exact temperature control the oxidation of ammonia can be run with increased and deliberately steered selectivity. A major application is provided by carrying out former high-temperature reactions in the low-temperature regime. In the case of ammonia oxidation in the chip micro reactor, the yield of the value product NO was actually lower in that regime. In the case of the multi-plate-stack micro reactor, higher yields of the value product NO2 were achieved. 

GP 2[ [R 2[ Safe operation under explosive conditions using pure oxygen was demonstrated in a steel multi-plate-stack micro reactor (e.g. 3 vol.-% ethylene, 50 vol.-% oxygen, balance nitrogen 5 bar 4 1 h 277 °C) ]4, 26,40]. The cross-sections of the various micro channels employed were from 500 x 50 pm to 500 x 90 pm. ... 

For a short description of the aims of experimental concentration cycling with respect to citraconic acid formation, see [13]. It is also demonstrated there that the response to rectangular concentration pulses for a given reactor configuration of a multi-channel-stack micro reactor can be improved by increasing the number of platelets and channels (while reducing their diameter). Such behavior was shovm for an incompressible fluid, i.e. is not solely related to the above-mentioned reaction. 

This class of hybrid components comprises chip micro-reactor devices, as described in Section 4.1.3, connected to conventional tubing. This may be H PLC tubing which sometimes has as small internals as micro channels themselves. The main function of the tubing is to provide longer residence times. Sometimes, flow through the tube produces characteristic flow patterns such as in slug-flow tube reactors. Chip-tube micro reactors are typical examples of multi-scale architecture (assembly of components of hybrid origin). 

The high surface-to-volume ratio can also significantly improve both thermal and mass transfer conditions within micro-channels in two ways firstly, the convective heat and mass transfers, which take place at the multi-phase interface, are improved via a significant increase in heat and mass transfer area per unit volume. Secondly, heat and mass transfers within a small volume of fluid take a relatively short time to occur, enabling a thermally and diffusively homogeneous state to be reached quickly. The improvement in heat and mass transfer can certainly influence overall reaction rates and, in some cases, product selectivity. Perhaps one of the more profound effects of the efficient heat and mass transfer property of micro-reactors is the ability to carry potentially explosive or highly exothermic reactions in a safe way, due to the relatively small thermal mass and rapid dissipation of heat. 

Fig. 2 shows a schematic diagram of a micro-channel of reformer section to be examined in this study. A multi-physics computer-aided numerical model framework integrating kinetics, mass transport, and flow dynamics in micro-channel reactors has been established. 

The numbering-up concept demands achieving absolutely uniform flow equi-partition by placing special headers in front of the parallel micro channels [5]. Although this has been solved for tubes in conventional multi-tubular reactors, the expenditure for equipartition in micro channel stacks is assumed to be higher, since the small channels may have more relative differences in structural preci-... 

GP18][R6] Experiments atfixedfiiowrate allowed a comparison of reactor performance over a VO /Al203 catalyst of a multi-platelet-stack micro-channel reac-torandaconventionalfixedbedasafunctionoftheinlettemperature[133,134j. 

This system is a chip version of three dimensional micro mixer-tube reactor setups [21]. It comprises a triangular interdigital micro mixer with a focusing zone that thins the multi-lamellae and a subsequent reaction channel that is surrounded... 

During the experiments, the micro structured reactor plant concept was also assessed by measuring properties such as seal reliability and thermal cross-talk between parallel fluidic channels. The performance of the micro structured reactor plant with respect to parameters such as product yield, selectivity and compactness, flexibility and robustness were examined using exemplary chemical reactions. These are advanced multi-step reactions in organometallic boron chemistry (liquid/liquid),... 

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