XRD and CO₂ Adsorption Studies of Modified Silica Gel with Octadecylamine

Abstract

Porous surface of silica gel (SG) have been modified with long and straight chain fatty amine compounds (octadecylamine, ODA) via wet impregnation process. SG was undergo heat treatment with various temperature which are 100, 200, 400 and 600 °C before continuing with impregnation process. Characterization by XRD of the treated samples were showed no significant different in their diffractograms. The best temperature for heat treatment was 600 °C and it was referred to the ability of the SG600 type adsorbents in adsorbing CO2 resulted from adsorption desorption isotherm of CO2. The 5 and 35 wt. % of ODA supported on the SG (ODA/SG600) was further characterized using XRD analysis which displayed the increasing intensity of crystalline ODA with higher percent amine loaded and shifting of the several crystalline peak of ODA verified the interaction of SG600-ODA. These further strengthen the prevailing dispersion of ODA on the surface of SG600.

Nano-imaging confirms improved apatite precipitation for high phosphate/silicate ratio bioactive glasses

“…For P0, this effect is apparent from 1 day of immersion, while for the other glasses the bands have virtually disappeared at 6 h. The corresponding appearance of an additional amorphous halo in XRD patterns (Fig. 1 ) at lower 2θ values illustrates the formation of an ion-depleted layer, typically referred to as silica gel layer 47 , 48 . FTIR band J appearing at 790 cm −1 also reflects silica gel formation, corresponding between vibrations between SiO 4 tetrahedra 20 .…”

Experimental Insights into Mesoporous Polyaniline-Based Nanocomposites for Anionic and Cationic Dye Removal

“…It is well known that SG, by its very nature, is amorphous, and thus no sharp peaks are observed in the XRD patterns of ASG (Figure b). The emergence of the diffraction peak at the 2θ range of 18.48–25.32 ̊ represent the amorphous phase of the ASG . Additionally, the diffractogram of bare ASG showed peaks at 2θ = 22°, again confirming the amorphous nature of silica …”

“…The emergence of the diffraction peak at the 2θ range of 18.48−25.32 ̊represent the amorphous phase of the ASG. 75 Additionally, the diffractogram of bare ASG showed peaks at 2θ = 22°, again confirming the amorphous nature of silica. 76 As shown in Figure 4c, all characteristics peaks for both Pani and ASG are evidently present with a reduced and short peak intensity in comparison with those of bare Pani and bare ASG.…”