Supercritical CO2-assisted amorphization of WO2.72 and its high-efficiency photothermal conversion

2020 ◽  
Vol 56 (56) ◽  
pp. 7805-7808
Author(s):  
Youzeng Li ◽  
Pengfei Yan ◽  
Cang Guo ◽  
Qun Xu
Keyword(s):  
Carbon Dioxide ◽  
Supercritical Carbon Dioxide ◽  
Conversion Efficiency ◽  
Supercritical Co2 ◽  
High Efficiency ◽  
Photothermal Conversion ◽  
Optical Absorbance ◽  
Treated Sample ◽  
Supercritical Carbon

Amorphization of WO2.72 was successfully achieved with the assistance of supercritical carbon dioxide (SC CO2). Amorphous SC CO2-treated sample has strong optical absorbance and excellent photothermal conversion efficiency of 52.5% indicates they can be a promising photothermal agent.

High-efficiency and minimum-waste continuous kinetic resolution of racemic alcohols by using lipase in supercritical carbon dioxide

2004 ◽  
pp. 2286 ◽  
Author(s):  
Tomoko Matsuda ◽  
Kazunori Watanabe ◽  
Tadao Harada ◽  
Kaoru Nakamura ◽  
Yoshitaka Arita ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Supercritical Carbon Dioxide ◽  
Kinetic Resolution ◽  
High Efficiency ◽  
Supercritical Carbon

scholarly journals Artificial Neural Network (FFBP-ANN) Based Grey Relational Analysis for Modeling Dyestuff Solubility in Supercritical CO2 with Ethanol as the Co-Solvent

2021 ◽  
Author(s):  
FNU SRINIDHI
Keyword(s):  
Carbon Dioxide ◽  
Supercritical Carbon Dioxide ◽  
Mean Square Error ◽  
Supercritical Co2 ◽  
Mean Absolute Error ◽  
Absolute Error ◽  
Mean Square ◽  
Relational Analysis ◽  
Grey Relational ◽  
Supercritical Carbon

The research on dye solubility modeling in supercritical carbon dioxide is gaining prominence over the past few decades. A simple and ubiquitous model that is capable of accurately predicting the solubility in supercritical carbon dioxide would be invaluable for industrial and research applications. In this study, we present such a model for predicting dye solubility in supercritical carbon dioxide with ethanol as the co-solvent for a qualitatively diverse sample of eight dyes. A feed forward back propagation - artificial neural network model based on Levenberg-Marquardt algorithm was constructed with seven input parameters for solubility prediction, the network architecture was optimized to be [7-7-1] with mean absolute error, mean square error, root mean square error and Nash-Sutcliffe coefficient to be 0.026, 0.0016, 0.04 and 0.9588 respectively. Further, Pearson-product moment correlation analysis was performed to assess the relative importance of the parameters considered in the ANN model. A total of twelve prevalent semiempirical equations were also studied to analyze their efficiency in correlating to the solubility of the prepared sample. Mendez-Teja model was found to be relatively efficient with root mean square error and mean absolute error to be 0.094 and 0.0088 respectively. Furthermore, Grey relational analysis was performed and the optimum regime of temperature and pressure were identified with dye solubility as the higher the better performance characteristic. Finally, the dye specific crossover ranges were identified by analysis of isotherms and a strategy for class specific selective dye extraction using supercritical CO2 extraction process is proposed.

scholarly journals Effect of CO2 Preservation Treatments on the Sensory Quality of Pomegranate Juice

Molecules ◽  
2020 ◽  
Vol 25 (23) ◽  
pp. 5598
Author(s):  
Ana Carolina Mosca ◽  
Leonardo Menghi ◽  
Eugenio Aprea ◽  
Maria Mazzucotelli ◽  
Jose Benedito ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Supercritical Carbon Dioxide ◽  
Supercritical Co2 ◽  
Sensory Quality ◽  
Pomegranate Juice ◽  
Process Conditions ◽  
Volatile Profile ◽  
Projective Mapping ◽  
Supercritical Carbon

Due to the interest in identifying cost-effective techniques that can guarantee the microbiological, nutritional, and sensorial aspects of food products, this study investigates the effect of CO2 preservation treatment on the sensory quality of pomegranate juice at t0 and after a conservation period of four weeks at 4 °C (t28). The same initial batch of freshly squeezed non-treated (NT) juice was subjected to non-thermal preservation treatments with supercritical carbon dioxide (CO2), and with a combination of supercritical carbon dioxide and ultrasound (CO2-US). As control samples, two other juices were produced from the same NT batch: A juice stabilized with high pressure treatment (HPP) and a juice pasteurized at high temperature (HT), which represent an already established non-thermal preservation technique and the conventional thermal treatment. Projective mapping and check-all-that-apply methodologies were performed to determine the sensory qualitative differences between the juices. The volatile profile of the juices was characterized by gas chromatography-mass spectrometry. The results showed that juices treated with supercritical CO2 could be differentiated from NT, mainly by the perceived odor and volatile compound concentration, with a depletion of alcohols, esters, ketones, and terpenes and an increase in aldehydes. For example, in relation to the NT juice, limonene decreased by 95% and 90%, 1-hexanol decreased by 9% and 17%, and camphene decreased by 94% and 85% in the CO2 and CO2-US treated juices, respectively. Regarding perceived flavor, the CO2-treated juice was not clearly differentiated from NT. Changes in the volatile profile induced by storage at 4 °C led to perceivable differences in the odor quality of all juices, especially the juice treated with CO2-US, which underwent a significant depletion of all major volatile compounds during storage. The results suggest that the supercritical CO2 process conditions need to be optimized to minimize impacts on sensory quality and the volatile profile.

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

ChemInform ◽  
2005 ◽  
Vol 36 (12) ◽  
Author(s):  
Tomoko Matsuda ◽  
Kazunori Watanabe ◽  
Tadao Harada ◽  
Kaoru Nakamura ◽  
Yoshitaka Arita ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Supercritical Carbon Dioxide ◽  
Kinetic Resolution ◽  
High Efficiency ◽  
Supercritical Carbon

scholarly journals Demonstration of the Allam Cycle: An Update on the Development Status of a High Efficiency Supercritical Carbon Dioxide Power Process Employing Full Carbon Capture

2017 ◽  
Vol 114 ◽  
pp. 5948-5966 ◽  
Author(s):  
Rodney Allam ◽  
Scott Martin ◽  
Brock Forrest ◽  
Jeremy Fetvedt ◽  
Xijia Lu ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Supercritical Carbon Dioxide ◽  
Carbon Capture ◽  
High Efficiency ◽  
Development Status ◽  
Supercritical Carbon

Combined Cycle Engine Cascades Achieving High Efficiency

2016 ◽  
Author(s):  
Andy Schroder ◽  
Mark G. Turner ◽  
Rory A. Roberts
Keyword(s):  
Carbon Dioxide ◽  
High Pressure ◽  
Fuel Cell ◽  
Supercritical Carbon Dioxide ◽  
High Efficiency ◽  
Waste Heat ◽  
Combined Cycle ◽  
Design Parameters ◽  
Topping Cycle ◽  
Supercritical Carbon

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.

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

2017 ◽  
Vol 88 (10) ◽  
pp. 1184-1212 ◽  
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.

scholarly journals Inspection for supercritical CO2 dyeing of poly(m-phenylene isophthalamide) by kinetics and thermodynamics analysis

2019 ◽  
Vol 14 ◽  
pp. 155892501988640
Author(s):  
Fang Ye ◽  
Guohua Liu ◽  
Ibrahim Khalil ◽  
Laijiu Zheng ◽  
Huanda Zheng ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Supercritical Carbon Dioxide ◽  
Diffusion Coefficients ◽  
Supercritical Co2 ◽  
Constant Pressure ◽  
Standard Entropy ◽  
Dye Uptake ◽  
Kinetics And Thermodynamics ◽  
Activation Energy For Diffusion ◽  
Supercritical Carbon

Eco-friendly dyeing by using supercritical carbon dioxide as a medium has already been investigated worldwide due to the advantages of dyeing without water and recyclability of dyes and carbon dioxide. In this article, dyeing mechanism of poly(m-phenylene isophthalamide) was investigated in supercritical carbon dioxide. The obtained results showed that the dye uptake of Disperse Red 60 increased moderately with the temperature raising at constant pressure and achieved dyeing equilibrium after 70 min. By adding the carrier, diffusion coefficients of Disperse Red 60 in the polymer increased significantly in supercritical carbon dioxide. The activation energy for diffusion of Disperse Red 60 with and without carrier was 1165.91 and 1050.66 kJ mol−1, respectively. Moreover, the distribution coefficient, the standard affinity, the standard enthalpy, and the standard entropy of dyeing were also determined in supercritical carbon dioxide. These fundamental data are of vital importance on the green dyeing production of poly(m-phenylene isophthalamide).

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

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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