Process macrobatch

Let us consider the reaction of A and B to give product P in a conventional macrobatch reactor, such as a round-bottomed glass flask (Figure 6.1). What kinds of processes occur when a solution of A is added to a solution of B, which is stirred magnetically or mechanically In order to simplify the discussion, we ignore the solvent. Thus, let us consider the addition of A to B. 

In this section, we discuss the cases where the use of microflow reactors allows us to conduct reactions under unconventional conditions, such as high temperatures, which significantly accelerate the rates of the reactions. In the macrobatch processes, however, the use of such reaction conditions may cause undesirable side reactions, such as the decomposition or subsequent reactions of products. Precise temperature control and short residence time, which minimize the consecutive side reactions, are responsible for successful reactions in microflow systems. 

Integration of a microreactor (StarLam 3000IMM microreactor) in an existing production plant (two-step batch process) has also been reported the reaction type is unveiled in the paper by Kirschneck and Tekautz- Installing a microreactor in the first reaction step leads to an increase in the capacity of the macrobatch process. An overall throughput of 3.6 ton/h has been achieved and the system has been running in production for more than a year. 

Because liquid-liquid nitration reactions are described in another chapter [15-19], this section deals with nitration reactions involving the gas phase. The nitration of naphthalene using N2O5 in both the gas phase (in situ production from N2O4 and O3) and the liquid phase has been carried out in microflow reactors under continuous flow conditions at 30 C (Scheme 8.10) [20,21]. The residence time is 3 s. The same reactions in conventional macrobatch operation require temperatures from —50 to —20°C to avoid undesired side-reactions. The isomer ratio of the dinitration products (C D) in a macrobatch process (1 3.6) is different from that for the microflow process (1 2.8). The isomer ratio of mononitration products (A B) can also be changed it is 20 1 for the macrobatch process and 32 1 for the microflow process. 

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