Recent advances in the design and fabrication of microchemical systems that include micromixers, microseparators and microreactors, brought closer the realization of desktop miniature factories and micro-pharmacies. They enabled simpler process optimization, rapid design implementation, better safety, easier scale-up through replication, allowing rapid product deployment to the marketplace and thus ensured a significant competitive edge....[ Read more ]

Recent advances in the design and fabrication of microchemical systems that include micromixers, microseparators and microreactors, brought closer the realization of desktop miniature factories and micro-pharmacies. They enabled simpler process optimization, rapid design implementation, better safety, easier scale-up through replication, allowing rapid product deployment to the marketplace and thus ensured a significant competitive edge.

Zeolitic materials possessing well-defined pore structures were incorporated inside microchemical systems. Two examples were illustrated in this study for the fabrication and application of zeolite-based miniaturized chemical systems.

The first example is the fabrication of micropatterned intergrown zeolite films with different orientations and chemical compositions. The patterns were constructed on silicon substrate using traditional semiconductor fabrication technique. The successful fabrication demonstrated that the developed method is a feasible technique in making arrays of micro-sized zeolite films for combinatorial applications.

In the second example, membrane microreactor with ZSM-5 zeolite membrane for selective water removal and CsNaX catalyst was designed and fabricated on a stainless steel substrate. Knoevenagel condensation of benzaldehyde and ethyl cyanoacetate was used as the test reaction. Product yield enhancement was resulted with the use of the membrane microreactor (from 30% in the laboratory scale reactor to about 80% in the membrane microreactor). The improvement can be explained by the combined advantages of a membrane reactor, which can improve reaction beyond thermodynamic constraints, and a microreactor, which can enhance external mass transfer. A mathematic model was developed for the membrane microreactor. The model suggested that a better-formulated catalyst could help to achieve 100% reactant conversion in the reaction.