Adsorption and diffusion of moisture and wet flue gas on silica gel

SummaryPermeation grouting with colloidal silica gel is a potentially effective means for creating hydraulic barriers to prevent the advective migration of radioactive contaminants in shallow permeable sediments. However, the effectiveness of silica gel grouted barriers in controlling transport of fission product radionuclides through sorption and diffusion is unknown. To resolve this question, static-batch sorption measurements with Cs

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Impact of porosity on calcination and sulfation of calcium sorbents

E3S Web of Conferences ◽

10.1051/e3sconf/20184900131 ◽

2018 ◽

Vol 49 ◽

pp. 00131

Author(s):

Renata Włodarczyk ◽

Michał Wichliński ◽

Zbigniew Bis

Keyword(s):

Grain Size ◽

Flue Gas ◽

Total Surface Area ◽

Chemical Processes ◽

Reactivity Indices ◽

Mean Diameter ◽

Mercury Porosimeter ◽

Capacity Index ◽

Reaction Furnace ◽

And Diffusion

The focus of the study was on sorbents with a grain size of 125-250 μm. Examinations of reactivity were conducted in a reaction furnace under conditions required for reactivity testing of calcium sorbents. The tests were performed according to standard calcium sorbent tests (FW). Computation of reactivity indices and capacity index were performed according to formulae contained in previous publications [1]. The process of simultaneous calcination and sulfation of calcium sorbents is controlled by the speed of chemical processes and diffusion. Therefore, surface properties of sorbents, including porosity, play an important role in the flue gas desulphurization process. Examinations of sorbent porosity were performed using a mercury porosimeter. Based on porosimetric analysis, open porosity, the total surface area of sorbents and mean diameter of pores were evaluated for the sorbents studied.

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Ionic cross-linked polyether and silica gel mixed matrix membranes for CO2 separation from flue gas

Separation and Purification Technology ◽

10.1016/j.seppur.2017.09.046 ◽

2018 ◽

Vol 191 ◽

pp. 301-306 ◽

Cited By ~ 10

Author(s):

Ali K. Sekizkardes ◽

Xu Zhou ◽

Hunaid B. Nulwala ◽

David Hopkinson ◽

Surendar R. Venna

Keyword(s):

Silica Gel ◽

Flue Gas ◽

Mixed Matrix Membranes ◽

Co2 Separation ◽

Mixed Matrix ◽

Matrix Membranes

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Meridional Circulation, Turbulence, and Diffusion Processes in Stars

International Astronomical Union Colloquium ◽

10.1017/s0252921100080477 ◽

1976 ◽

Vol 32 ◽

pp. 109-116 ◽

Cited By ~ 1

Author(s):

S. Vauclair

Keyword(s):

Convection Zone ◽

Diffusion Processes ◽

Meridional Circulation ◽

Diffusion Time ◽

Work In Progress ◽

First Results ◽

Stellar Envelopes ◽

And Diffusion ◽

Turbulence And Diffusion ◽

Hr Diagram

This paper gives the first results of a work in progress, in collaboration with G. Michaud and G. Vauclair. It is a first attempt to compute the effects of meridional circulation and turbulence on diffusion processes in stellar envelopes. Computations have been made for a 2 Mʘstar, which lies in the Am - δ Scuti region of the HR diagram.Let us recall that in Am stars diffusion cannot occur between the two outer convection zones, contrary to what was assumed by Watson (1970, 1971) and Smith (1971), since they are linked by overshooting (Latour, 1972; Toomre et al., 1975). But diffusion may occur at the bottom of the second convection zone. According to Vauclair et al. (1974), the second convection zone, due to He II ionization, disappears after a time equal to the helium diffusion time, and then diffusion may happen at the bottom of the first convection zone, so that the arguments by Watson and Smith are preserved.

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