Multiplicity regions in the synthesis of MTBE

Implications for process control. Avoiding multiplicity is certainly an important consideration for process control and its interactions with design (Chen et al., 2002). An appropriate control configuration is an effective tool to avoid multiplicity. Giittinger and Morari (1997) show, for the MTBE column studied by Jacobs and Krishna (1993), that 

3 Additional Modeling Implications for Multiple Steady States 

Equilibrium (EQ) and non-equilibrium (NEQ) models are generally used to represent the governing phenomena in RD. Lately, the effect of the modeling approach on the occurrence of MSS has become a hot topic within the CAGE community. This trend is easily evident by listing the recent publications on EQ and NEQ models and their im- 

The physical and chemical behavior of the system requires the definition of key design decision variables. For one-stage and multistage levels those decision parameters and operational variables include operational pressure and temperature, chemical reaction kinetics i.e. equilibrium or rate-limited chemical reaction), mass/heat transfer regime, phase velocity, residence time of the reactive phase and temporal operation i.e. batch, fed batch and continuous). 

Note that appropriate choices for those design decision variables are closely linked to the challenges of process design and operation of reactive distillation (c/. section 1.2.2). Thus, for instance, the development of novel catalyst should take into account both 

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