N-formylmorpholine (NFM) is an important organic solvent and fine chemical raw material because of its good Due to its solubility, high boiling point and relatively low toxicity and corrosiveness, it is widely used in many industrial fields, such as aromatic hydrocarbon extraction, butene concentration, and natural gas desulfurization. The production process of NFM mainly involves the esterification reaction of morpholine and methyl formate as raw materials, usually in the presence of a catalyst. The following is a typical production process flow of N-formylmorpholine:
Raw material preparation:
- Morpholine: A six-membered cyclic nitrogen-containing compound that serves as the amine component of the reaction.
- Methyl formate: Methyl formate acts as an acylating agent and provides a formyl group.
Catalyst selection:
- The choice of transesterification catalyst is crucial to the reaction efficiency. Commonly used catalysts include sodium alkoxide, potassium alkoxide, organotin, titanate and their compounds, such as sodium methoxide, potassium methoxide, sodium ethoxide, potassium ethoxide, Sodium tert-butoxide, potassium tert-butoxide, dibutyltin oxide, dioctyltin oxide, butyl titanate, etc.
Reaction conditions:
- Mass ratio: The mass ratio of morpholine and methyl formate is usually 1.30~1.74:1 to ensure sufficient acylation reaction.
- Catalyst dosage: The amount of catalyst added is generally 0.5% to 5% of the total weight of raw materials to promote the transesterification reaction.
- Reaction pressure: The reaction can be carried out in the range of normal pressure to 0.6Mpa.
- Reaction temperature: The appropriate reaction temperature range is 30~120? to balance the reaction rate and the suppression of side reactions.
- Reaction time: The reaction time is usually set between 2 and 6 hours to ensure the completeness of the reaction.
Separation and purification:
- Batch separation process:
- Separation and recovery of methyl formate: through distillation, the operating pressure is 0.1~0.2Mpa, the reactor temperature is controlled at 68~82°C, and the methyl formate fraction is collected at the top of the tower.
- Separation and recovery of methanol: Change the distillation pressure to normal pressure, raise the reactor temperature to 68~130°C, and collect methanol at the top of the tower.
- Separation and recovery of morpholine: the crude product is filtered to remove the catalyst, and then distilled under a vacuum of 0.09~0.099MPa, the reactor temperature is 130 ~155?, morpholine is collected at the top of the tower.
- Obtaining N-formylmorpholine: Maintain the above vacuum degree, raise the reactor temperature to 155~165°C, and collect N-formylmorpholine from the top of the tower.
- Continuous separation process:
- Similar to intermittent separation, but the entire process is carried out in continuous flow equipment, including flash tanks, evaporators, light component towers and vacuum product towers, etc., to improve efficiency and reduce energy consumption.
Product quality:
- The N-formylmorpholine produced should be a colorless and transparent liquid that meets specific quality standards, such as purity, color, moisture content and other indicators.
The production process of N-formylmorpholine is a complex chemical engineering process that requires precise control of reaction conditions and separation steps to ensure the quality of the product quality and yield. As technology develops, continuous process optimization and improvement are necessary to increase production efficiency and reduce environmental impact.
Extended reading:
Toyocat MR Gel balanced catalyst tetramethylhexamethylenediamine Tosoh
