Acid Scavenging The BASIL Process

The ionic liquid is acting as an auxiliary. Specific benefits of the ionic liquid are  

Scavenging with a tertiary amine results in a thick, non-stirrable slurry (Fig. 9-2). These problems significantly lower the yield and capacity of the process. In order to provide a minimum of mixing and heat transfer of the exothermic reaction a solvent usually has to be added. 

How can ionic liquids (dis)solve the problem. If an acid has to be scavenged with a base, the formation of a salt caimot be avoided, but why not form a liquid salt instead. The idea of BASF researchers was to use an ionic 

During the reaction two clear liquid phases occur (Fig. 9-3) that can easily be separated. The upper phase is the pure product - solvent is no longer needed -the lower phase the pure ionic liquid, l-methyl-imidazolium chloride as an ionic liquid has a great advantage over the classical dialkylated systems it can be switched 

Only recently an eco-eSiciency analysis has shown that the BASIL technology is by far more sustainable than the process using tertiary amines [9]. 

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