Abstract:

In butadiene extraction units by acetonitrile process, acetonitrile solvent needs to be continuously regenerated to maintain its quality. Solvent regeneration is limited for the existing process, and large amounts of impurities cannot be removed effectively. A solvent regeneration technology is developed. Without changing the existing process, the impurities such as alcohols, ketones and butadiene polymer can be removed to obtain a solvent with an acetonitrile content of 94.6％ (mass fraction), thus solving the problem of limited solvent regeneration, improving the solvent quality and prolonging the production cycle of the unit. Pro II software is used to simulate the regeneration process and determine the main process parameters of distillation tower. Less than 1％ acetonitrile is lost in this unit, and the comprehensive energy consumption per ton of acetonitrile product is 76.25 kg.

Key words: butadiene, acetonitrile process, solvent regeneration, process simulation.