A

where W is leakage rate (kg h"1), A0 is hole area on the tray (m2) and h, is liquid height on the tray (m).

Therefore, for the coupled reaction and distillation processes with gas-liquid-solid three-phase, we can safely obtain the information necessary for the equipment design on the tray column and extend to the industry, which have important practical values.

2.2. Alkylation of benzene and propylene

Here alkylation of benzene and propylene is studied as the example of FCD and SCD. The reaction between benzene and propylene is very popular in industry because the product, cumene, as a basic chemical material is mainly produced from this reaction. In order to accurately simulate the SCD process, it is important to know the intrinsic rate equations for this reaction system. It is known that the reactions include alkylation reaction that is irreversible and transalkylation reaction that is reversible. For transalkylation reaction, the reaction equilibrium constant can be referred in the reference [83], But for alkylation reaction, the kinetic data for a given catalyst must be determined experimentally.

In general, the kinetic property of a chemical reaction, which is carried out in a distillation column, should be measured separately, e.g. in a fixed-bed reactor. Moreover, in the case of heterogeneously catalysed reactions, special attention should be paid to the mass and energy transport resistances inside the catalyst. Thus one has to study carefully both intrinsic and apparent kinetics of the reaction system. Herein, it is assumed that the intrinsic reaction rates are the same as global reaction rates because the employed catalyst particles in the SCD process are so tiny that mass and energy transport resistances inside and outside the catalyst particles can be neglected.

A modified 3 -zeolite catalyst, YSBH-01, developed from our laboratory, was used in the investigation. It has high activity and selectivity for the reaction. The kinetic performance of this catalyst was experimentally studied in a fixed-bed micro-reactor. On this basis, the equilibrium stage model (MESHR equations) is programmed. Moreover, a novel SCD process, in which alkylation and transalkylation reactions are carried out simultaneously in a single column, is suggested and the performance of SCD and FCD processes is discussed in terms of the EQ stage model.

2.2.1. Reaction kinetics

The involved reaction network includes alkylation and transalkylation reactions and is written as:

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