For commodity chemicals, low profit margins drive the need for high-performing, cost effective, and atom-efficient chemical operations. Thus, commodity chemicals are usually produced in thoroughly optimized, dedicated continuous production plants. In contrast, pharmaceuticals are generally more complex and usually require numerous, diverse reaction steps for their synthesis (typically 6 to 10 synthetic steps). These requirements, together with the comparatively low production volumes and short life times of many pharmaceuticals, make versatile and reconfigurable multipurpose batch reactors the technology of choice for their preparation. However, despite their prevalence in the pharmaceutical industry, batch-type reactors have some well-recognized limitations. Continuous flow and microreactor technology provides an appealing alternative to batch reactors. Continuous processes offer several well established advantages, and they have the potential to reduce production costs, increase product yield and product consistency, and strengthen process robustness. Process development and scale-up is facilitated by the adoption of continuous flow reactors in the early stages of molecule discovery and synthesis. However, the selection of the optimal reactor technology in these applications is not trivial and requires a thorough understanding of the reaction kinetics, flow patterns, and phases.
In this talk, the advantages and challenges of continuous flow processes will be discussed and the concept of mini-monoplant technology will be introduced. Recent examples will be given to demonstrate the versatility of continuous processing in the field of API manufacturing. The pharmaceuticals can then be produced in miniaturized and intensified production assets (mini-monoplant). This allows a high degree of flexibility and rapid response to fluctuations in product demand.