Figure 1. Schematic diagram of the
continuous flow adsorption system.
As Figure 1 shows, a permeation tube containing CH3I was
placed in the Dynacalibrator, which air (Airgas Inc. Air, Ultra Zero)
flowed through as the carrier gas. The mixture then passed through the
pre-heating coil around the adsorption tube (inner diameter = 30mm) and
reached the adsorbent placed in the tray. During the adsorption process,
the mass change was measured by the microbalance and the data were
recorded by the computer.
Additionally, to prevent the counterweight from being oxidized, the
continuously flowing nitrogen (Airgas Inc. Nitrogen, Ultra High Purity)
was used as the protective gas. The temperature of the adsorption system
was controlled by the temperature controller and the connected furnace;
the flow rate of the adsorbate mixture was controlled by the mass flow
controller.
Silver Functionalized Silica
Aerogel
In this presented work, silver functionalized silica aerogel
(Ag0-Aerogel) was selected to be the adsorbent for its
high silver concentration and high aging resistance.20The shape and size of Ag0-Aerogel is relatively uneven
and the average density and diameter of the material is 0.58
g/cm3 and 0.2 cm, respectively. The iodine adsorption
capacity was measured experimentally to be approximately 37-38 wt%.
The compositions of the as-received Ag0-Aerogel
measured by SEM-EDX and XPS are listed in Table 1.