Manufacturing method of 2-octanol
I. Introduction
2-octanol is an important organic chemical raw material, which is widely used in the fields of fine chemicals, pharmaceuticals, spices and so on. Due to its unique chemical properties and wide range of applications, it is of great practical significance to study the manufacturing method of 2-octanol. In this paper, the process route of preparing 2-octanol by aldehyde condensation method with ethylene as raw material will be introduced in detail, including the reaction principle, process flow, equipment selection and other aspects.
II, reaction principle
The reaction principle of preparing 2-octanol by aldehyde condensation method mainly includes two steps: firstly, ethylene and synthesis gas (CO and H2) under the action of catalyst, carbonyl synthesis reaction occurs to generate propionaldehyde; then propionaldehyde and n-butyraldehyde under the action of acid catalyst, condensation reaction occurs to generate 2-octanol.
Three, process flow
1. Ethylene carbonyl synthesis of propionaldehyde
After mixing ethylene and syngas according to a certain ratio, it is passed into the reactor equipped with catalyst, and the carbonyl synthesis reaction is carried out under suitable temperature and pressure conditions to produce propionaldehyde. The reaction product is cooled and separated to obtain the crude product of propionaldehyde.
2. Condensation of propionaldehyde with n-butyraldehyde to form 2-octanol
After mixing the crude propionaldehyde with n-butyraldehyde in a certain ratio, an acidic catalyst was added, and the condensation reaction was carried out at a suitable temperature to form 2-octanol. The reaction product is distilled and separated to get 2-octanol finished product. IV. Equipment Selection
1. Reactor
Fixed-bed reactor is selected to carry out the reaction of ethylene carbonyl synthesis of propionaldehyde, and the catalyst adopts rhodium-based catalyst. The reactor is equipped with temperature control system and pressure control system to ensure stable reaction conditions. Distillation tower
2. Plate distillation tower is selected for the separation and purification of the reaction products, in order to realize the separation of crude propionaldehyde and 2-octanol products. The distillation tower is equipped with temperature and pressure control system to ensure the stability of the separation effect and product purity.
V. Operating conditions and optimization
1. Temperature
In the reaction of ethylene carbonyl synthesis of propionaldehyde, the suitable reaction temperature is 120-150 ℃; in the reaction of condensation of propionaldehyde with n-butyraldehyde to form 2-octanol, the suitable reaction temperature is 80-100 ℃. By controlling the reaction temperature, the reaction rate and selectivity can be improved.
2. Pressure
In the reaction of ethylene carbonyl synthesis of propionaldehyde, the suitable reaction pressure is 1.5-2.5MPa; in the reaction of condensation of propionaldehyde with n-butyraldehyde to form 2-octanol, the suitable reaction pressure is atmospheric pressure. By controlling the reaction pressure, the reaction rate and equilibrium can be influenced.
3. Catalyst activity and lifetime
The activity and lifetime of the catalyst have a large influence on the reaction. Therefore, when selecting catalyst, its performance in terms of activity, selectivity and lifetime should be considered. Meanwhile, the catalyst needs to be regenerated or replaced periodically during operation to maintain its activity.
4. Purity and proportion of raw materials
The purity and proportion of raw materials also have a large influence on the reaction. Therefore, the purity and proportion of raw materials should be strictly controlled during the operation to ensure the smooth progress of the reaction and the quality of the products.
VI. Safety and environmental protection
In the production process, safety operation regulations should be strictly observed to ensure production safety. Meanwhile, the treatment of waste gas, waste water and solid waste should be strengthened to reduce the pollution to the environment.
VII.Conclusion
The preparation of 2-octanol by aldehyde condensation is a feasible process route, which has the advantages of mild reaction conditions, high selectivity, and high product purity. In the actual production process, suitable equipment and operating conditions should be selected according to the specific situation in order to improve the production efficiency and product quality. Meanwhile, safety and environmental protection management should be strengthened to ensure smooth production and sustainable development.
