Simulation And Optimization Of New Process To Produce N-Butyl Acetate By Catalytic Distillation

N-butyl acetate is of excellent performance as an organic, which is widely used in the pharmacy and the painting. Conventionally, sulfuric acid is often used as catalyst in the esterification of acetic acid. Although the rate of conversion is high in the process, many problems exists, such as too much secondary reaction, serious corrosion, complicated final treatment and pollution. The new technology to produce n-butyl acetate by continuously catalytic distillation technique with solid acid catalyst was combined with chemical reaction and separation process by reaction distillation tower. It had many advantages to produce n-butyl acetate by continuously catalytic distillation technique with solid acid catalyst, such as higher conversion, better selectivity, lower energy consumption, more simple operation, less investment, higher efficiency, less corrosion and side-reaction, and so on. It has been applied in industry and yielded a good economic returns.However, the technology still need to be improved, ie. the concentration of acid in crude ester is quite high, which needs neutralization, and the more out-feed decreases the efficiency. So on the basis of previous simulation and optimization, two parts of the technology were modified. Firstly, the previous single reaction section was changedinto three parts, the upper part is distillation section with partial condensation, the middle the reaction section and the below the stripping section. The upper distillation section has many advantages, such as the inner automatic adjustment of reflux, faster responding speed controlled by reflux and lower energy consumption. It has good applying prospective in the batch distillation and the azeotropic distillation. Secondly, the neutralization process was removed between the reaction tower and distillation tower, and the direct distillation can also remove small quantity of acetic acid.By use of Visual C++, the whole modified process after calculating the distillation tower and reaction tower was simulated respectively, and the operation rule and optimum operation condition was obtained. The results showed that the quality of n-butyl acetate was satisfactory, the old process reduced, and the efficiency was quite higher after being modified. Therefore the feasibility and superiority of new technology was proved in theory, and the direction and instruction for the next research was put forward.