In conventional chemical engineering, there is a broad range of reactors to perform gas-liquid-solid reactions.The choice of one reactor relies on many parameters such as kinetics, heat and mass transfer performances as well as production output.The advent of micro/milli-teehnology over the past decade opened new operating windows for production with a new type of reactors [1], which include miniaturized rectors [2] and/or structured reactors [3].This technology has demonstrated its interest by achieving high mass and heat transfers [4], better control of the reaction and increased safety.The scale-up issues are then considered through numbering-up, saving process development time and money.