Investigation of carbon monoxide gas adsorption on the Al2O3/Pd(NO3)2/zeolite composite film

Abstract

In this study, Al 2 O 3 /Pd(NO 3) 2 /zeolite composite films have been fabricated by roll coating method and characterized by X-ray diffraction, energy-dispersive X-ray spectroscopy and field emission scanning electron microscopy. The gas adsorption was tested in an experimental setup by a continuous gas analyzer KIMO KIGAZ 210 at constant temperature and pressure (32 °C and 1.5 bar) and as a function of reaction time (s). The inlet CO gas concentration was 150 mg L −1 , and the saturation level of CO gas concentration was 5 mg L −1. The maximum adsorption capacity (q max) and maximum adsorption efficiency (%) were calculated as 111.16 mg g −1 and 97%, respectively. Pseudo-first-order, pseudo-second-order, and intra-particle diffusion models were investigated to kinetic study of CO adsorption on Al 2 O 3 /Pd(NO 3) 2 /zeolite adsorbents. Results indicated that CO adsorption follows the pseudo-second-order model well according to regression coefficient value (R 2 = 0.98), and the value of pseudo-second-order rate constant of adsorption was obtained as 2 × 10 −5 g mg −1 s −1. According to the intra-particle diffusion model, adsorption is affected by only one process. So, adsorption of CO by Al 2 O 3 /Pd(NO 3) 2 /zeolite adsorbent indicated an effective adsorption by obtained results.

Kinetics study of CO molecules adsorption on Al2O3/Zeolite composite films prepared by roll-coating method

“…1-methyl-2-pyrrolidone (10cc) was added dropwise into the beaker containing γ-Al 2 O 3 and Zeolite, and kept on a magnetic stirrer (Model: HS 860). Stirring was continued for 1 h at room temperature in a closed beaker before the Al 2 O 3 /Zeolite was deposited on glass substrates by the roll-coating method [32]. To study CO adsorption capacity and efficiency of Al 2 O 3 /Zeolite composite films, four Al 2 O 3 /Zeolite coated substrates were used to make a hollow cubic container [32].…”

“…Zeolite adsorbent at a constant temperature and pressure. It is observed that over time the adsorbed CO concentration (mg L −1 ) increased while the speed of adsorption reduced due to the developing saturation level [32].…”

“…Among silica-and alumina-based materials, mesoporous alumina (MA) has been studied more for toxic gas adsorption [14,[41][42][43][44][45]. It is worth mentioning that aluminium oxide (Alumina, Al 2 O 3 ) is one of the useful materials that can be used as a gas adsorbent, catalyst, and so on [32,[46][47][48][49][50][51][52][53][54][55][56][57]. Chemical inertness from oxidizing, high stability, and durability from molten metals and non-metals are all remarkable properties of alumina [46].…”

“…On the other hand, zeolite nanoparticles are crystalline aluminosilicate that include porous three-dimensional frameworks consisting of SiO 4 and AlO 4 tetrahedral units. This material is used as an adsorbent due to its uniform pore structure, large surface area, and high selectively [32,[62][63][64][65].…”

Influence of the sputtering glancing angle on the microstructure and adsorption characteristics of Zr-Co-RE getter films

“…As can be seen, there is no obvious high intensity diffraction. All films have almost same pattern and exhibit only one broad diffraction peak at around 2θ=36°, which suggest that the Zr-Co-RE films are amorphous or nanocrystalline structure [17,32,38]. The full-width at half maximum (FWHM) of the peaks is 4.98 (0°), 5.73 (30°), 5.58 (60°), 4.38 (90°), respectively.…”