Novel process windows in flow : from chemical to process-design intensification - from green chemistry to green engineering

Novel Process Windows in Flow: From Chemical to Process-Design Intensification - from Green Chemistry to Green Engineering Volker Hessel, Timothy Noel, Qi Wang Eindhoven University of Technology, Department of Chemical Engineering and Chemistry, Micro Flow Chemistry and Process Technology, Eindhoven, The Netherlands Micro Process Technology has given strong push to continuous chemical manufacture via facilitating heat and mass transfer (transport intensification). The next big step is to develop a tailored process chemistry in flow under highly intensified conditions – which is one essence among the developing field of Flow Chemistry. This has been coined Novel Process Windows [1-4] and has two research pillars, – the exploration of unusual and typically harsh process conditions (chemical intensification) and, in a more holistic picture, a completely new and often simpler process design (process-design intensification). The 1,3-Huisgen cycloaddition (Click Chemistry), the Claisen and Johnson-Claisen rearrange-ments, the Heck C-C coupling, the Hantzsch dihydropyridine synthesis, and the H2O2-based direct adipic acid synthesis are processed harshly and chemically intensified [2-4]. Click Chemistries can be integrated in multi-step (tandem, cascade, …) synthesis which is done at the example of Rufin¬amide synthesis (Top200 drug) [3,4]. All reactions stand for generic approaches to boost reactivity via high-T, high-p, high-c (solvent-free; alternative solvent) concepts and more. Recently, bio¬technology and flow chemistry merged into enzymatic micro¬reactors (alpha amino alcohols from Threonine Aldolase, transesterifications from Lipase) [5]. Main issue here is to achieve producti¬vity, sufficient at least for pharma level. Starting from such new reaction designs, new process designs in flow are developed, such as the large-scale industrial direct adipic acid [6] and hydro¬formy¬lation processes [3,4]; with major conse¬quences on CAPEX/OPEX costs [5,7] sustainability [8,9], and energy consumption (heat integration, pinch analysis). The industrial exploitation of Novel Process Windows was tested at the example of soybean oil epoxidation [2,9]. On top of that, the embedment of flow processing into modern compact modular chemical production platforms (‘Future Factories’; container) such as Evonik’s Evotrainer is discussed. A recent cash-flow analysis gives evidence on net-present value and financial risk-assessment for the three main markets in chemistry which are pharma, fine-chemical and bulk-chemical [10]. [1] V. Hessel, Chem. Eng. Technol. 32, 11 (2009) 1655-1681. [2] V. Hessel, B. Cortese, M.H.J.M. de Croon, Chem. Eng. Sci. 66, 7 (2011) 1426-1448. [3] V. Hessel, D. Kralisch, N. Kockmann, T. Noel, Q. Wang, Q., ChemSusChem (2013) DOI: 10.1002/cssc.201200766. [4] S.C. Stouten, T. Noël, Q. Wang, V. Hessel, Aust. J. Chem. 66, 2 (2013) 121-130. [5] I. Dencic, J. Meuldijk, M.H.J.M. de Croon, V. Hessel, J. Flow Chem. 1, 1 (2011) 13-23. [6] M. Shang, T. Noël, Q. Wang, V. Hessel, V., Chem. Eng. Technol. (2013) online. [7] F. Benaskar, V. Hessel, L.A. Hulshof, J.C. Schouten et al., J. Flow Chem. 1, 2 (2011) 74-89. [8] Q. Wang, I. Vural–Gürsel, M. Shang, V. Hessel, Energy Environm. Sci. (2013) submitted. [9] D. Kralisch, D., E. Santacesaria, B. Cortese, V. Hessel et al., ChemSusChem 5, 2 (2012) 300-311. [10] I. Vural–Gürsel, V. Hessel, Q. Wang, T. Noël, J. Lang, Green Process. Synth. 1, 4 (2012) 309-404.