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Mleczko L.,Bayer AG | Zhao D.,Bayer Technology and Engineering Shanghai Co.
ACS Symposium Series | Year: 2014

This chapter introduces the concepts of flow technology primarily in relationship to the use of organolithium reagents and reactions, and describe a workflow for flow chemistry and micro-reaction technology along with the necessary infrastructure with suitable equipment at different scales for the lithiation of chloroarenes. This work highlights the many advantages of flow chemistry in transferring a potentially hazardous laboratory scale reaction into a viable large scale operation. In all aspects, continuous lithiation of fluoroaromatics was superior to the corresponding batch processes. © 2014 American Chemical Society.

Yuan Y.,Yangzhou University | Zhu H.,Yangzhou University | Zhao D.,Bayer Technology and Engineering Shanghai Co. | Zhang L.,Yangzhou University
Synthesis | Year: 2011

The catalytic Sonogashira coupling reaction of terminal alkynes and aryl halides is developed using copper(II) oxide nanoparticles as catalyst in dimethyl sulfoxide. The procedure is experimentally simple, general, efficient, and free from addition of external cocatalysts or chelating ligands. © Georg Thieme Verlag Stuttgart - New York.

Wang Y.-J.,Fujian New Wuhuan Engineering Design Co. | Zhu H.-S.,Bayer Technology and Engineering Shanghai Co. | Zhai J.-G.,Shanghai Research Institute of Chemical Industry
Petrochemical Equipment | Year: 2015

The theory background for prevention of brittle fracture in ASME VIII-1 - 2013 is introduced. The requirements for impact test exemption curves, impact test energy value, low stress service and loading rate are analyzed and discussed also. © 2015, Lanzhou Petroleum Machinery Research Institute. All rights reserved.

Xie D.,East China University of Science and Technology | Zhou J.,East China University of Science and Technology | Tian S.,Bayer Technology and Engineering Shanghai Co. | Mleczko L.,Bayer AG | Zhou X.,East China University of Science and Technology
Chemical Engineering and Technology | Year: 2016

A cascade mixer and a valve mixer were applied for the precipitation of CaCO3. This model reaction has been used for benchmarking both mixer types with respect to their robustness against fouling. The valve mixer was found to be much less susceptible to fouling and clogging. Pressure changes during precipitation in both types of mixers differed significantly. This parameter can be easily used for identification of clogging in the valve mixer and applied as input in clean-in-place (CIP) procedures. The pressure trend in the cascade mixer is quite complex and, therefore, difficult to apply for CIP. Ultrasonic treatment has been evaluated as a measure to prevent clogging. Copyright © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Zhao D.,Bayer Technology and Engineering Shanghai Co. | Ding K.,CAS Shanghai Institute of Organic Chemistry
ACS Catalysis | Year: 2013

Asymmetric catalysis in flow has been attracting much attention very recently because of the potential advantages over its batchwise counterpart, such as high-throughput screening and synthesis, easy automation with the integration of on-demand reaction analysis, little or no reaction workup, and potential long-term use of the catalysts in the case of heterogeneous catalysis. Homogeneous asymmetric catalysis performed in a microreactor has demonstrated successful examples in fast catalyst screening, integrated inline/ onlineanalysis, microflow photocatalysis, multistep transformation with unstable intermediates, and potential for lower catalyst loading or homogeneous catalyst recylcing. Since heterogeneous asymmetric catalysis serves as a better way than its homogeneous analogue for catalyst separation and recycling, this Review Article summarizes recent development via different catalyst immobilization methods, such as covalent support, a self-supported method, an adsorption method, and H-bonding, electrostatic or ionic interaction, and nonconventional media, as well. In addition, biocatalysis, including enzyme-catalyzed kinetic resolution and transformation, in flow will be discussed either in homogeneous or heterogeneous mode. © 2013 American Chemical Society.

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