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The overall productivity of the aqueous biphasic hydroformylation of the castor oil‐derived methyl 10‐undecenoate is increased. To increase the reaction rate, the miscibility of water and the fatty compound is increased by addition of the green solvent 1‐butanol as co‐solvent. For the first time, the concentration of solvents, substrate, and product within the reaction process is experimentally examined in a biphasic system under 20 bar pressure of synthesis gas and 140 °C. A reactor to get samples of both phases is developed to determine the quarternary mixture of the reaction system presented in a four‐dimensional tetrahedron diagram. With the knowledge gained about the reaction and its drivers, it is possible to increase the efficiency of the reaction process reported so far. With simultaneously high reaction rates (turn over frequency = >5000 h−1), the space–time yield of the reaction reaches values of >120 g L−1h−1 and can be improved significantly without negatively affecting catalyst leaching. Practical Applications: Most polymers are made of petrochemicals. Here, the development of a highly efficient process for the formation of bifunctional molecules starting from technical grade methyl 10‐undecenoate made from castor oil in an aqueous biphasic reaction system is presented. By rhodium catalyzed hydroformylation, an aldehyde ester is formed which can be used to create alcohols, carboxylic acids, and amines. Subsequently, these molecules can be used as polymer precursors in polycondensation reactions. [ABSTRACT FROM AUTHOR]

In two case studies, the reaction performance of the aqueous biphasic hydroformylation of two industrially relevant oleochemicals, namely methyl 10‐undecenoate (case 1) and methyl oleate (case 2), is significantly improved by the use of a Jet‐Loop Reactor concept. Based on previously reported studies, only the two green and benign co‐solvents, 1‐butanol and isopropanol are applied, respectively, in the absence of any additional auxiliary. Both reactions benefit highly from using this special piece of equipment, specifically designed for improving gas–liquid–liquid mixing to create large interfacial areas with no moving internals. In case 1, the loading of the co‐solvent 1‐butanol is successfully reduced. For the first time significant yields (>40% after 1 h) are obtained in the absence of any co‐solvent, which is very beneficial, since aldehyde products and substrate form a pure product phase enabling straightforward separation. In case 2, the loading of the substrate methyl oleate is successfully increased from 6 to 30 wt% still showing satisfying productivity. At 15 wt%, the yield of the desired internal aldehydes in the jet‐loop reactor is increased by a factor of five compared to a stirred tank reactor after 3 h. Practical Applications: The production of aldehydes from hydroformylation of olefins is highly relevant for the chemical industry, since these can undergo numerous subsequent reactions, to form for instance alcohols, amines, and carboxylic acids. Generally, aldehydes from oleochemicals can serve as platform chemicals for gaining access to bifunctional molecules, which are interesting as polymer precursors. Performing hydroformylation with a water‐based solvent system enables efficient product separation from the aqueous catalyst phase for the realzation of more sustainable processes. By using the Jet‐Loop Reactor, the performance of the reaction system can be greatly improved addressing its practical relevance. [ABSTRACT FROM AUTHOR]

Over the past 20 years, thermomorphic multiphase systems (TMS) have been used as a versatile and elegant strategy for the recovery and recycling of homogeneous transition-metal catalysts, in both batch-scale experiments and continuously operated processes. TMS ensure a homogeneous reaction in a monophasic reaction mixture at reaction temperature and the recovery of the homogeneous transition-metal catalyst through liquid-liquid separation at a lower separation temperature. This is achieved by using at least two solvents, which have a highly temperature-sensitive miscibility gap. The suitability of commercially available solvents makes this approach highly interesting from an industrial point of view. For the first time, herein, all studies in the area of TMS are reviewed, with the aim of providing a concise and integral representation of this approach for homogeneous catalyst recovery. In addition to the discussion of examples from the literature, the thermodynamic fundamentals of the temperature-dependent miscibility of solvents are also presented. This review also gives key indicators to compare different TMS approaches, for instance. In this way, new solvent combinations and in-depth research, as well as improvements to existing approaches, can be addressed and promoted., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A new process concept has been developed for recycling transition-metal catalysts in the synthesis of moderately polar products via aqueous thermomorphic multicomponent solvent systems. This work focuses on the use of "green" solvents (1-butanol and water) in the hydroformylation of the bio-based substrate methyl 10-undecenoate. Following the successful development of a biphasic reaction system on the laboratory scale, the reaction was transferred to a continuously operated miniplant to demonstrate the robustness of this innovative recycling concept for homogenous catalysts., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)