共查询到11条相似文献,搜索用时 15 毫秒
1.
Adsorption isotherms for supercritical fluids are calculated using lattice theory. Results are compared with experimental data for methane on graphon and for carbon dioxide on coal. It is shown that the model reflects the peculiar features in adsorption isotherms of supercritical fluids (in particular, a maximum in the adsorption with increasing pressure). The analysis shows that there is two layer adsorption over a wide range of densities. 相似文献
2.
This paper deals with gravimetric measurements of adsorption equilibria of gases on the surface of porous solids with a new
type of magnetic suspension balance. Items discussed include the measurement of adsorption data at high pressure and temperature
as well as the simultaneous measurement of adsorption and the density of the adsorptive gas using only one magnetic suspension
balance.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
3.
In the present work the supercritical fluids argon, methane and nitrogen were picked out as examples, and the results of analysis concerning the adsorption of these fluids at activated carbon Norit R1 (Norit company, Germany) and SCS-3 (ISPE, Kiev) at different temperatures up to a pressure of 50 MPa are presented and discussed in this paper. The principle of working of the measuring device is described in this context as well.A three-parameter isothermal equation is used to represent the adsorption equilibrium. The isothermal equation is based on a physical model concept which has already been used for the modelling of adsorption processes with a pressure up to 15 MPa. 相似文献
4.
Adsorption equilibria of pure gases and binary gas mixtures can be measured with a new magnetic suspension balance. For this measurement no additional concentration measurement is required, neither for the gas phase nor for the adsorbed phase. The new instrument allows gravimetric adsorption measurements in a wide range of pressure (UHV...50 MPa) and temperature (210 K...570 K) to be performed. The experimental procedure and the instrument set up is fairly easy and can be compared to pure gas adsorption experiments. The new instrument and experimental procedure have been tested by performing coadsorption measurements with CO/H2 mixtures on a commercial 5A zeolite.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
5.
Physisorption equilibria of multicomponent gases on microporous solids like zeolites or activated carbons are considered.
An overview about adsorption measurements of pure gases H2, He, O2, N2, Ar, CO2, CO, CH4, C2H4 and C2H6 and some of their mixtures in the pressure range vacuum < p < 50 MPa at different temperatures 10∘C–70∘C were investigated. Also a thermodynamic formalism based on a modified van Ness method and on a new 3 parameter Isotherm equation (3-PIG) to describe the excess amount adsorbed was developed. Results are
shown and discussed.
Dedication to the memory of W. Schirmer. 相似文献
6.
In the present work the supercritical fluids argon, methane, nitrogen, carbon dioxide, ethane, ethylene and propane were picked out as examples, and the results of analysis concerning the adsorption of these fluids at activated carbon Norit R1 (Norit Company, Germany) and SCS-3 (ISPE, Kiev) at different temperatures up to a pressure of 50 MPa are presented and discussed in this paper. The principle of working of the measuring device is described in this context as well.A three-parameter isothermal equation is used to represent the adsorption equilibrium. The isothermal equation is based on a physical model concept which has already been used for the modelling of adsorption processes with a pressure up to 15 MPa.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
7.
Adsorption data of the pure gases ethane, methane and their mixtures on zeolite 13X and the pure gases carbon dioxide, nitrogen and their mixtures on activated carbon Norit R1 were measured gravimetrically at a temperature of 298 K and pressures up to 15 MPa. From the total loads the partial loads were calculated by the modified van Ness approach. The calculated loads show a good agreement with the experimental data. 相似文献
8.
《Electroanalysis》2003,15(17):1397-1402
A new analytical procedure for the simultaneous determination of aluminum(III) and iron(II) in two kinds of dialysis fluids (peritoneal and hemodialysis fluids) by differential pulse adsorptive stripping voltammetry (DPAdSV) is described. The voltammetric measurements were performed using, as working electrode, a stationary mercury electrode, and a platinum electrode and a Ag|AgCl|KCl(sat.) electrode as auxiliary and reference electrodes, respectively, employing acetate buffer solutions at different pH as supporting electrolyte. As complexing agents, Solochrome Violet RS, Palatine Chrome Black 6BN, Chromazurol S and Eriochrome Black T were employed. For both elements, the accuracy, expressed as relative recovery R%, was very satisfactory being in the range 94–105%, the precision as repeatability, expressed as relative standard deviation sr%, was lower than 6%, while the limits of detection were of the order of a few units of μg/L. The analytical voltammetric procedure has been validated by comparison with spectroscopic (graphite furnace atomic absorption spectroscopy, GFAAS) measurements. 相似文献
9.
Kazuhiko Hagiwara Tatsuya Yamazaki Sentaro Ozawa 《Journal of colloid and interface science》1995,170(2)
Adsorption of acetonitrile from toluene solution at a liquid-solid interface under pressures of up to 300 MPa was investigated by IR spectroscopy. The CN stretching vibration bands (vCN) of adsorbed acetonitrile were observed at higher frequencies than those of the same species in the liquid phase. The shift on alumina-pillared montmorillonite (ALPM) was the largest (ca. 8 cm-1) for the adsorbents studied. The vCN intensities of adsorbed acetonitrile on ALPM and on alumina (Al2O3) considerably increased with increased pressure, indicating an increase acetonitrile adsorption due to compression. It was concluded that the total volume of the system was reduced by adsorption, and that the reduction was brought about not only by the formation of an adsorption bond but also by the change in the solvation of the adsorbate in the adsorbent pore. 相似文献
10.
Y. Dali M. Tupin P. Bossis F. Valdivieso M. Pijolat 《Journal of Thermal Analysis and Calorimetry》2009,96(1):155-160
The fuel claddings in the Pressurised Water Reactor are corroded in water at high temperature and high pressure. The technical
device ableto follow continuously the corrosion rate in conditions close to this medium does not yet exist. That is the reason
why a high pressure thermogravimetric installation based on magnetic suspension has been designed to study in situ the oxidation
kinetics of the zirconium based alloys under water vapour until 50 bars of pressure at 415°C. The accuracy of measurements
is about 5·10−5 g under 2 bars, and 10−4 g under 50 bars. The reproducibility of measurements was verified and the deviation regarding post test weighing at room
temperature is around 5·10−5 g what is clearly satisfying. Finally, the results presented in this work allow validating the high pressure thermogravimetric
measurements obtained with this magnetic suspension device. 相似文献