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1

Development of separation methods for a continuous hydroformylation process in a mini-plant scale

Müller D., Müller M., Nguyen L. A. T., Ludwig J., Drews A., Kraume M., Schomäcker R., Wozny G.

Czasopismo Techniczne. Mechanika

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2012

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R. 109, z. 1-M

165--174

EN

In this contribution a novel process concept for the continuous hydroformylation of long chained alkenes to aldehydes in micro emulsion mixtures with the aid of a hydrophilic rhodium−ligand−complex catalyst is discussed. The challenging aspects with regards to the technical and economic feasibility of the process concept are the separation steps to recycle the expensive catalyst. To investigate and optimize the described process concept, a mini-plant is built at the Berlin Institute of Technology. Due to the lack of thermodynamic data, the design of the crucial separation steps, decanter and micellar enhanced ultrafiltration (MEUF), strongly depend on experimental data. Therefore, “small scale” experiments are designed with adequate similarity to the actual units in the plant. The information gained therein leads to improvements for the separation steps and helps to determine operating parameters for the mini-plant.

PL

W artykule niniejszym omówiona zostaje nowatorska koncepcja procesowa dotycząca ciągłej hydroformylacji alkenów łańcuchowych do aldehydów w mieszaninach mikroemulsyjnych za pomocą wodochłonnego katalizatora typu rod-ligand. Wyzwanie w odniesieniu do technicznej i ekonomicznej wykonalności koncepcji procesowej stanowią stopnie oddzielania prowadzące do odzyskania kosztownego katalizatora. W Berlińskim Instytucie Technologicznym zbudowano mini-aparaturę służącą do badania i optymizowania opisanej koncepcji procesowej. Ze względu na brak danych termodynamicznych projekt najważniejszych etapów oddzielania – wzmożonej ultrafiltracji dekanterowej i micelarnej (MEUF) – zależy w znacznym stopniu od danych doświadczalnych. Dlatego też eksperymenty prowadzone na „niedużą skalę” przygotowywane są z zachowaniem właściwego podobieństwie do rzeczywistych elementów aparatury. Zebrane informacje prowadzą do ulepszeń w zakresie stopni oddzielania, pomagając określać operacyjne parametry mini-aparatury.

2

Hydroformylacja w środowisku cieczy jonowych

Trzeciak A. M.

Wiadomości Chemiczne

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2011

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[Z] 65, 11-12

1003-1020

EN

The hydroformylation reaction was discovered by Otto Roelen in 1938. He studied the side processes occurring during the Fischer-Tropsch synthesis with a cobalt catalyst and found some amounts of aldehydes formed from the olefin and syngas (H2/CO) [1]. The hydroformylation found application in the chemical industry, mainly for production of n-butanal from propene. Aldehydes obtained by propene hydroformylation are subsequently hydrogenated to alcohols, used as solvents. Butanal can also be condensed to C8 aldehydes and alcohols, 2-ethylhex-2-enal and 2-ethylhexanol, important components for plasticizers such as dioctylphtalate. The hydroformylation reaction can be applied not only for the synthesis of aldehydes but also for other products. In particular, successful synthesis of quaternary carbon centers by hydroformylation has been reported in which the rhodium catalyst was modified with a ligand that serves as a catalytic directing group by covalently and reversibly binding to both the substrate and the catalyst. Ionic liquids have been recognized as a novel class of solvents which can be successfully used for homogeneous catalysis [4]. Application of ionic liquids, non-aqueous and non-volatile solvents, has made it possible to construct biphasic systems in order to efficiently separate catalysts from organic products. It is also important that the properties of ionic liquids, such as solubility, acidity, or coordination ability, can be tuned by the use of different cations and anions. In the ideal case, the ionic liquid is able to dissolve the catalyst and displays partial miscibility with the substrate. If the products have negligible miscibility in the ionic liquid, they can be removed by simple decantation, without extracting the catalyst. If the products are partially or totally miscible in the ionic liquid, separation of the products is more complicated [4e, 4h]. The main problem with catalytic systems for hydroformylation containing ionic liquid phase was a significant leaching of the catalyst out of the ionic liquid phase, which can be overcome by modifying neutral phosphane with ionic groups. Examples of such systems are presented in the article. It was revealed that N-heterocyclic carbenes were formed in the biphasic hydroformylation reactions promoted by Rh complexes in an imidazolium ionic liquid [10]. Consequently, reactivity of the in situ formed Rh-carbene complexes can strongly influence on the hydroformylation reaction course [11]. The best methodology to perform the hydroformylation reaction would be a flow system in which the catalyst remains in the reactor and the substrates and products flow continuously into and out of the reactor. For the construction of such a system with soluble rhodium catalysts, ionic liquids could be considered as media used for the immobilization of the catalyst. The first example of continuous flow hydroformylation was reported by Cole-Hamilton [19, 20]. Different Supported Ionic Liquid Phase (SILP) catalysts have been examined in hydroformylation [15–17]. Interestingly, the neutral ligand can be applied efficiently in a continuous gas-phase SILP process, while in a typical biphasic system containing ionic liquid and organic solvent it would leach into the product phase.

3

Homogeniczne i heterogenizowane katalizatory rodowe w reakcjach hydroformylacji związków nienasyconych

Trzeciak A. M., Ziółkowski J. J.

Przemysł Chemiczny

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2006

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T. 85, nr 2

96-100

PL

Przedstawiono ogólne wprowadzenie do szeroko stosowanych w przemyśle procesów hydroformylacji związków nienasyconych (monoolefin, dienów i nienasyconych alkoholi). Podsumowano ponad 25-letnią działalność naukową w zakresie syntezy, badań strukturalnych i reaktywności katalitycznej kompleksów rodu w reakcjach hydroformylacji, izomeryzacji i uwodornienia prowadzonych na Wydziale Chemii Uniwersytetu Wrocławskiego.

EN

A review with 30 refs. covering selected problems of hydroformylation based on studies conducted at the Faculty of Chemistry University of Wroclaw. The influence of P ligand type on the selectivity of hydroformylation of monoolefins, dienes and unsaturated alcohols and the reactivity of rhodium catalysts supported on Al2O3 – ZrO2 and on SiO2 are discussed.