Table 4. Input condition and result of RDC.

Reactive Distillation: Modeling, Simulation, and Optimization DOI: http://dx.doi.org/10.5772/intechopen.85433

Figure 6. Flow sheet of methyl acetate RDC.

increasingly stringent environmental regulations, and global competition in product pricing and quality. One of the most important engineering tools for addressing these issues is optimization. Modifications in plant design and operating procedures have been implemented to reduce costs and meet constraints, with an emphasis on improving efficiency and increasing profitability. Optimal operating conditions can be implemented via increased automation at the process, plant, and company levels, often called computer-integrated manufacturing. Computers and associated software make the necessary computations feasible and cost-effective [22–25].

Steady-state simulation of methyl acetate esterification was carried out using Aspen Plus simulator. Radfrac module, NRTL property method, and other operating conditions such as feed condition, feed location, operating pressure, column configuration including number of stages and reaction stage, type of condenser, type of reboiler, and feed flow rate of the components used are specified in Aspen Plus environment. The specification and other results are included in Table 4. The simulation flow sheet is shown in Figure 6. The product purity is attaining a highest value at the top stage. The composition profile of the column is shown in Figure 7. As shown in figure, the maximum composition of product methyl acetate obtained is 95.4%. The amount of methanol and acetic acid is much lower at the top of the column; this indicates the complete consumption of reactants and formation of product.

The temperature profile of the column is shown in Figure 8. As shown in figure, we can clearly observe that the temperature of the reactive section is higher than the other section; this is because of the exothermic nature of the esterification reaction. Also, temperature of reboiler is higher than the temperature at condenser. As it can be observed from the figure, the condenser temperature which is 57.4°C is lower than reboiler temperature which is 62.7°C. The temperature of the reactive zone is varied between 61.3 and 77.8°C, making it compatible to the exothermic nature of

Input condition Methanol Acetic acid

50°C 0.03 L/min

10, including reboiler and condenser 3–6 (reactive zone) 2–3 7–9

> 70°C 0.05 L/min

Parameters Values

Reboiler heat duty 0.2 kW Reflux ratio 5 Condenser temperature 57.40°C Distillate rate 10.56 mole/hr Reflux rate 52.81 mole/hr Reboiler temperature 62.66°C Bottom rate 86.12 mole/hr Boil up rate 23.62 mole/hr Boil up Ratio 0.274

No. of stages Reactive stage Rectifying stage Stripping stage

Temperature Flow rate

Table 4.

102

Input condition and result of RDC.

9.1 Steady-state simulation and optimization

Distillation - Modelling, Simulation and Optimization

Figure 7. Composition profile of methyl acetate RDC.

the esterification reaction. The maximum temperature of the condenser during experiment was 58°C, and the temperature of the condenser obtained from Aspen Plus was 57.4°C, which shows good agreement between experimental and simulation results.
