Benzene, C6H6 elastic moduli, melting point, vapor pressure

Carbon dioxide, either as an expanded liquid or as a supercritical fluid, may be a viable replacement for a variety of conventional organic solvents in reaction systems. Numerous studies have shown that many reactions can be conducted in liquid or supercritical CO2 (sc CO2) and, in some cases, rates and selectivities can be achieved that are greater than those possible in normal liquid- or gas-phase reactions (other chapters in this book; Noyori, 1999; Savage et al., 1995). Nonetheless, commercial exploitation of this technology has been limited. One factor that contributes to this reluctance is the extremely complex phase behavior that can be encountered with high-pressure multicomponent systems. Even for simple binary systems, one can observe multiple fluid phases, as shown in Figure 1.1. The figure shows the pressure–temperature (PT) projection of the phase diagram of a binary system, where the vapor pressure curve of the light component (e.g., CO2) is the solid line shown at temperatures below TB. It is terminated by its critical point, which is shown as a solid circle. The sublimation curve, melting curve, and vapor pressure curve of the pure component 2 (say, a reactant that is a solid at ambient conditions) are the solid lines shown at higher temperatures on the right side of the diagram; that is, the triple point of this compound is above TE. The solid might experience a significant melting point depression when exposed to CO2 pressure [the dashed–dotted solid/liquid/vapor (SLV) line, which terminates in an upper critical end point (UCEP)]. For instance, naphthalene melts at 60.1 °C under CO2 pressure (i.e., one might observe a three-phase solid/liquid/vapor system), even though the normal melting point is 80.5 °C (McHugh and Yogan, 1984). To complicate things even further, there will be a region close to the critical point of pure CO2 where one will observe three phases as well, as indicated by the dashed–dotted SLV line that terminates at the lower critical end point (LCEP). The dotted line connecting the critical point of the light component and the LCEP is a vapor/liquid critical point locus.

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Experimental Investigation to the Properties of Eutectic Salts by NaCl-KCl-ZnCl2 for Application as High Temperature Heat Transfer Fluids

Volume 1: Combined Energy Cycles, CHP, CCHP, and Smart Grids; Concentrating Solar Power, Solar Thermochemistry and Thermal Energy Storage; Geothermal, Ocean, and Emerging Energy Technologies; Hydrogen Energy Technologies; Low/Zero Emission Power Plants and Carbon Sequestration; Photovoltaics; Wind Energy Systems and Technologies ◽

10.1115/es2014-6578 ◽

2014 ◽

Cited By ~ 2

Author(s):

Kai Wang ◽

Edgar Molina ◽

Ghazal Dehghani ◽

Ben Xu ◽

Peiwen Li ◽

...

Keyword(s):

Heat Transfer ◽

High Temperature ◽

Melting Point ◽

Vapor Pressure ◽

Mole Fraction ◽

Heat Transfer Fluid ◽

Test Facility ◽

Vapor Pressures ◽

Heat Transfer Fluids ◽

Temperature Heat

A group of eutectic ternary halide salts were surveyed and studied for the objective of developing a high temperature heat transfer fluid with a freezing point below 250°C and a low vapor pressure, below 1.0 atm, at temperatures up to 800°C. The studied salts include: 1) NaCl-KCl-ZnCl2 with a mole fractions of 18.6%-21.9%-59.5% and a melting point of tm=213°C; 2) NaCl-KCl-ZnCl2 with a mole fraction of 13.4%-33.7%-52.9% and a melting point of tm=204°C; and 3) NaCl-KCl-ZnCl2 with mole fraction of 13.8%-41.9%-44.3% and a melting point of tm=229 °C. Vapor pressures of these salts at different temperatures were experimentally obtained using an in-house developed test facility. The results show that vapor pressures of all the three eutectic molten salts are below 1.0 atm at a temperature of 800 °C. The salt of ZnCl2-KCl-NaCl in mole faction of 44.3%-41.9%-13.8% has lowest vapor pressure which is only about 1.0 atm even at a temperature of 900 °C. Viscosities of these salts were measured in the temperature range from after melting to 850°C. At low temperatures near their melting points of the salts, the viscosities are about 16 × 10−3Pa s, while at high temperatures above 700°C the viscosities are around 4 × 10−3Pa s, which is satisfactorily low to serve as heat transfer fluid for circulation in a CSP system. Both the vapor pressure and the viscosities of the studied three eutectic salts demonstrated satisfaction to serve as high temperature heat transfer fluids. Other thermal and transport properties of these salts are expected to be reported in the future for screening out a satisfactory high temperature heat transfer fluid.

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Zinc oxide (ZnO) Debye temperature, heat capacity, density, melting point, vapor pressure, hardness

II-VI and I-VII Compounds; Semimagnetic Compounds - Landolt-Börnstein - Group III Condensed Matter ◽

10.1007/10681719_312 ◽

2005 ◽

pp. 1-5

Author(s):

Keyword(s):

Heat Capacity ◽

Zinc Oxide ◽

Melting Point ◽

Vapor Pressure ◽

Debye Temperature ◽

Temperature Heat

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The Vapor Pressure and Melting Point of Graphite

The Journal of Chemical Physics ◽

10.1063/1.1746759 ◽

1948 ◽

Vol 16 (12) ◽

pp. 1165-1166 ◽

Cited By ~ 7

Author(s):

Leo Brewer

Keyword(s):

Melting Point ◽

Vapor Pressure

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Study for Radionuclide Transfer Ratio of Aerosols Generated During Heat Cutting

11th International Conference on Environmental Remediation and Radioactive Waste Management, Parts A and B ◽

10.1115/icem2007-7139 ◽

2007 ◽

Cited By ~ 1

Author(s):

Yukihiro Iguchi ◽

Tsutomu Baba ◽

Hiroto Kawakami ◽

Takashi Kitahara ◽

Atsushi Watanabe ◽

...

Keyword(s):

Melting Point ◽

Vapor Pressure ◽

Test Sample ◽

Inert Gas ◽

Metallic Elements ◽

High Vapor Pressure ◽

Transfer Ratio ◽

Air Atmosphere ◽

Arc Melting ◽

High Vapor

The metallic elements with a low melting point and high vapor pressure seemed to transfer in aerosols selectively at dismantling reactor internals using heat cutting. Therefore, the arc melting tests of neutron irradiated zirconium alloy were conducted to investigate the radionuclide transfer behavior of aerosols generated during the heat cutting of activated metals. The arc melting test was conducted using a tungsten inert gas welding machine in an inert gas or air atmosphere. The radioactive aerosols were collected by filter and charcoal filter. The test sample was obtained from Zry-2 fuel cladding irradiated in a Japanese boiling water reactor for five fuel cycles. The activity analysis, chemical composition measurement and scanning electron microscope observation of aerosols were carried out. Some radionuclides were enriched in the aerosols generated in an inert gas atmosphere and the radionuclide transfer ratio did not change remarkably by the presence of air. The transfer ratio of Sb-125 was almost the same as that of Co-60. It was expected that Sb-125 was enriched from other elements since Sb is an element with a low melting point and high vapor pressure compared with the base metal (Zr). In the viewpoint of the environmental impact assessment, it became clear that the influence if Sb-125 is comparable to Co-60. The transfer ratio of Mn-54 was one order higher compared with other radionuclides. The results were discussed on the basis of thermal properties and oxide formation energy of the metallic elements.

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