Recycling of Auxiliary, Side and Intermediate Products

In selective gas-phase oxidation processes the conversion often does not reach 100%, in order to reduce total oxidation. This means that some starting material and/or intermediate products are present in the reaction mixture. Following separation, these may be recycled into the reaction to avoid yield losses. Although the above may seem obvious, an economical and efficient recycling procedure is not always simple, depending on the volatility of the components involved and the concentration of any unwanted by-products. In practice, a purge is included in the recycle to maintain an equilibrium concentration of by-products. 

Green Principles in Lonza s Niacinamide Process (5000 mtpa) 

Although this route has the same fundamental weakness of being coupled to another product (adiponitrile), the future of nylon 6,6 and the route to its 

The 3-picoline produced has a very high isomeric purity. 

Picoline is produced in a two-stage catalytic process that is practically energetically neutral an endothermic (ring closure) and an exothermic (dehydrogenation) reaction. 

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Recycling of auxiliary, side-, and intermediate products into the process. 

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