Millimeter reactors with micro-structured-Matrix for multi-phase catalytic reactions – MILLIMATRIX

The emergence of microreactors and process miniaturization over the past decade has provided a potentially new platform for accelerating the development of next-generation catalysts and multiphase catalytic process technologies. Due to increased process intensification offered by the microreactors, more traditional pilot-scale reactor systems and pilot plant systems can be replaced by smaller, faster responding and more flexible mini-plants with reduced operating costs and environmental impact. Some projects are running at the European scale, such as the IMPULSE ANR project which deals with the design of equipments and micro-processes for pharmaceuticals and fine chemical production and a pilot-scale device is running since recently at Degussa AG facilities in Frankfurt.
However actually, the microreactors still present again the different drawbacks:

- Most microreactors that were designed in open literature had characteristic channel cross-sectional dimension of few hundreds of ?m. Consequently, the enabling techniques of miniaturization are not very easy and must also be considered. Moreover in the channel, the problem of plugging during the manufacturing exists.
- From a catalytic point of view, another negative aspect of the ‘conventional’ microreactor is the inhomogeneous deposition of the washcoat layer onto the microreactor channel and thus the unstability of the washcoat/reactor wall interface.

In this context, we propose a project (MILLIMATRIX) that has already been evaluated positively last year as it was on the complementary list of the A.N.R JCJC and that we have slightly modified according to referees recommendations.
It is based on the development of millimeter structured reactors in order to propose alternative solutions for overcoming the usual above-cited drawbacks of microreactors. It is therefore fully focused on the investigation and the development of a new promising multi-scale structured technology (MILLIMATRIX) based on millimeter reactor volume filled by a micro cellular matrix (?-SiC foam with or without addition of nanofibers). The originality of our project consists in using a millimeter reactor (which is easier to machine than conventional microreactors). The S/V ratio value will be increased - not by reducing the size of reactor channel - but by introducing a nano/micro cellular matrix previously coated with a catalytic phase (i.e. using directly ex-situ the ‘conventional’ techniques of deposition of active phase on solid foam). The tuneable morphology of the solid foam (cell size, macroscopic porosity, strut diameter, addition of nanofibers) will ensure local fluid recirculation which are favourable to heat and mass transfer. The concept of the new family of reactor (MILLIMATRIX reactors), which must to answer the different gaps of microreactor cited above, is to hierarchically structure the reactor from the macro-scale to the micro-scale. In this project, both model reactions and multi-phase reactions will be used in order to characterize this new millimeter structured reactor. This project will be based on previous results from the MILLICAT ANR project which focused on the control of the coating of the walls of microstructures by the active phase.