High-Efficiency and Minimum-Waste Continuous Kinetic Resolution of Racemic Alcohols by Using Lipase in Supercritical Carbon Dioxide.

Two combined cycle engine cascade concepts are presented in this paper. The first uses a traditional open loop gas turbine engine (Brayton cycle) with a combustor as the topping cycle and a series of supercritical carbon dioxide (S–CO2) engines as intermediate cycles and a bottoming cycle. A global optimization of the engine design parameters was conducted to maximize the combined efficiency of all of the engines. A combined cycle efficiency of 65.0% is predicted. The second combined cycle configuration utilizes a fuel cell inside of the topping cycle in addition to a combustor. The fuel cell utilizes methane fuel. The waste heat from the fuel cell is used to heat the high pressure air. A combustor is also used to burn the excess fuel not usable by the fuel cell. After being heated, the high pressure, high temperature air expands through a turbine to atmospheric pressure. The low pressure, intermediate temperature exhaust air is then used to power a cascade of supercritical carbon dioxide engines. A combined efficiency of 73.1% using the fuel lower heating value is predicted with this combined fuel cell and heat engine device. Details of thermodynamics as well as the (S–CO2) engines are given.

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Supercritical carbon dioxide as a green media in textile dyeing: A review

Textile Research Journal ◽

10.1177/0040517517697639 ◽

2017 ◽

Vol 88 (10) ◽

pp. 1184-1212 ◽

Cited By ~ 25

Author(s):

Tarek Abou Elmaaty ◽

Eman Abd El-Aziz

Keyword(s):

Carbon Dioxide ◽

Supercritical Carbon Dioxide ◽

High Efficiency ◽

Manufacturing Processes ◽

Great Role ◽

Textile Dyeing ◽

Save Energy ◽

Natural Fabrics ◽

Supercritical Carbon

This review highlights the great role of supercritical carbon dioxide fluid technology in textile dyeing processes. The unequivocal physical characteristics of supercritical carbon dioxide are presented and further researched to continue the development of high efficiency, compact dyeing to save energy and water in manufacturing processes. This review also focuses on the solubility of the dyes in scCO2 as well as the application of the technology to both synthetic and natural fabrics. Some factors relating to the economics of sustainable scCO2 technology are also outlined.

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Effect of Flow Acceleration and Buoyancy on Thermalhydraulics of sCO2 in Mini/Micro-Channel

Handbook of Research on Advancements in Supercritical Fluids Applications for Sustainable Energy Systems - Advances in Chemical and Materials Engineering ◽

10.4018/978-1-7998-5796-9.ch005 ◽

2021 ◽

pp. 161-182

Author(s):

Nitesh Kumar ◽

Dipankar Narayan Basu ◽

Lin Chen

Keyword(s):

Carbon Dioxide ◽

Supercritical Carbon Dioxide ◽

Supercritical Fluids ◽

High Efficiency ◽

Thermal Characteristics ◽

Flow Acceleration ◽

Power Cycle ◽

Numerical Studies ◽

Major Interest ◽

Supercritical Carbon

Supercritical fluids have found enhanced applications in several sectors. High efficiency and high compactness associated with supercritical carbon dioxide power cycle are of major interest to the thermal engineers. Additionally, due to environment friendly properties, such as zero ODP, considerably lower GWP, non-toxic and nonflammable supercritical carbon dioxide has emerged as a potential substitute of conventional refrigerants. The peculiar properties of supercritical fluids ensured distinct flow and thermal characteristics of supercritical systems. Therefore, the chapter is aimed to discuss the thermalhydraulic characteristics of supercritical carbon dioxide in minichannel and microchannel. Both experimental and numerical studies on flow and thermal behavior of supercritical carbon dioxide will be discussed. The focus of this chapter is to examine the effect of buoyancy and flow acceleration on heat transfer performance. Considering the widespread applicability, the comprehensive discussion introduced in the chapter will affirmatively help the researchers.

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Dynamic Kinetic Resolution of Sec-Alcohols in Ionic Liquids/Supercritical Carbon Dioxide Biphasic Systems

International Journal of Chemical Reactor Engineering ◽

10.2202/1542-6580.2106 ◽

2009 ◽

Vol 7 (1) ◽

Cited By ~ 4

Author(s):

Pedro Lozano ◽

Teresa De Diego ◽

Michel Vaultier ◽

Jose L Iborra

Keyword(s):

Carbon Dioxide ◽

Ionic Liquids ◽

Supercritical Carbon Dioxide ◽

Kinetic Resolution ◽

Immobilized Lipase ◽

Enzymatic Catalysis ◽

Chemical Properties ◽

Dynamic Kinetic Resolution ◽

Biphasic Systems ◽

Supercritical Carbon

Supercritical fluids and ionic liquids are neoteric solvents that can be used as non-conventional reaction media for enzymatic catalysis under optimised conditions. These solvents exhibit many different physical and chemical properties, but have two cross-points: they are not-miscible and can be easily separated from substrates and products, and they can be reused. As supercritical carbon dioxide (scCO2) can dissolve in the ionic liquid (IL) phase (up to 0.7 mole fraction), a new concept of biphasic bioreactors for Fine Chemicals syntheses may be developed by using both enzyme and chemical catalysts "immobilized" into the IL phase, and substrates transported by the scCO2 phase. The system was tested for the continuous chemoenzymatic dynamic kinetic resolution (DKR) of rac-1-phenylethanol in IL/scCO2 by using simultaneously immobilized lipase (Novozym 435) and acid zeolites catalysts at 50°C and 100 bars, providing good yields (up 98.0 %) for R-phenylethyl propionate ester with excellent enantioselectivity (up to 97.3 %), and without any activity loss after 14 days of operation.

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