RATE-BASED MODEL and EXPERIMENTAL Investigation to Produce Ethyl TERT-Butyl Ether FROM TERT-Butanol and Ethanol USING Batch Packed REACTIVE Distillation

Wednesday, October 19, 2011: 5:20 PM
205 A (Minneapolis Convention Center)
Nada B. Nakkash and Nadeen K. Al-Janabi, Chemical Engineering, Al-Nahrain University, Baghdad, Iraq


     The present work concerned with studying the behavior of packed reactive distillation column using Rate-Based or Non- Equilibrium (NEQ) model to produce ethyl tert-butyl ether (ETBE) experimentally and theoretically. A batch packed reactive distillation unit with a heat resistance glass distillation column packed with glass rasching rings of 3mm inside diameter has been used to produce Ethyl Tert-Butyl Ether from Ethanol (ETOH) and Tert-Butanol (TBA) using KHSO4 as a homogeneous catalyst at atmospheric pressure. The effect of many variables on ETBE purity such as feed molar ratio of Ethanol to Tert-Butanol (1:1, 2:1, 4:1), reflux ratios (3, 4, and 5), boiler heat duties of (65, 90, and 146 W), and the amount of catalyst have been studied, when the catalyst and the reactants are mixed in the still.

    The best operating conditions obtained are feed molar ratio (FMR) 1:1, reflux ratio 5, boiler heat duty 146W, for this operating conditions an experiment was carried out using an intermediate reactive section of 28 cm length with KHSO4 catalyst. ETBE purity and conversion increased to 79.41% and 99.465% respectively which are higher than that gained from reactive still but it needs large amounts of catalyst.   

   Theoretically, a Rate-Based or Non-Equilibrium (NEQ) model was developed using MATLAB (R2009b). The performance and validity of the developed NEQ model gave a good agreement with the experimental work. Also, the results of NEQ model are compared with the results of equilibrium model for the same system from the previous work.

     The comparison of the NEQ and EQ models with experimental work shows that the profiles of the NEQ model is nearer to the experimental profiles than those of equilibrium model profiles since the NEQ model taking into account the effect of heat and mass transfer. The comparison of EQ and NEQ models showed that there is a difference between the two models which is due to the consideration of a Murphee vapor efficiency of 1 in the equilibrium model.

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