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The properties of three types of CoMo/USY catalysts with different synthesized methods have been studied. The sequential and co-impregnation methods followed by activation using calcination and reduction process have been conducted. The properties of the catalysts were examined using Fourier-transform-infrared (FTIR) spectroscopy, X-ray diffraction (XRD) with refinement, and surface area analyzer (SAA). The FTIR spectrum study revealed the enhanced intensity of its Bronsted acid site, and the XRD diffractogram pattern verified the composition of pure metals, oxides, and alloys in the catalyst. The SAA demonstrated the mesoporous features of the catalyst. Scanning electron microscopy showed an irregular particle morphology. Additional analysis using the transmission electron microscopy indicated that the metal has successfully impregnated without damaging the USY structure.

Structural and dynamical properties of Cu+ in 18.6% aqueous ammonia solution at 298.15 K have been investigated via quantum mechanical charge field molecular dynamics (QMCF MD). The QM region was set to a radius of 6.7 A to include the first and second solvation shell. The Hartree-Fock (HF) level was applied to calculate the ion-ligand and ligand-ligand interactions in the QM region using the LANL2DZ-ECP basis set for the ion and DZP-Dunning for the ligands. The Cu+ N and Cu+ O radial distribution functions showed maximum first shell probabilities at distances of 2.23 and 2.30 A, respectively. Predominantly, four NH3 molecules were found to form a tetrahedral [Cu(NH3)4]+ complex, although the formation of a short-lived intermediate [Cu(NH3)3H2O]+ complex was also observed. The mean residence times of NH3 and H2O ligands in the first solvation shell were estimated as 14.6 ps and 1.3 ps, respectively, reflecting the strong interaction between Cu+ and ammonia as well as the occurrence of rapid water exchange. The vibrational power spectrum of the Cu+ N vibration in the first solvation shell revealed a wave number of 252 cm−1 with a corresponding force constant of 43.0 Nm−1. In addition, an NBO analysis was carried out, confirming the strong electrostatic character of the Cu+ NH3 and Cu+ H2O interaction, and highlighting that the presence of H2O ligands may destabilize the first solvation shell.

Rb(I) ion solvation in liquid ammonia has been studied by an ab initio quantum mechanical charge field molecular dynamics simulation, and the first solvation shell structure has been analyzed using natural bond orbital. The simulation was performed for an ion and 593 ammonia molecules in a box with a length of 29.03 A corresponding to a liquid ammonia density of 0.69 g/mL at 235.16 K. The quantum mechanical calculation was carried out for atomic interactions in the radius of 6.4 A from the ion using LANL2DZ ECP and DZP (Dunning) basis sets for Rb(I) ion and ammonia respectively. The trajectories of the simulation were analyzed in terms of radial, angular, and coordination number distribution functions, vibration, and mean residence time (MRT). Two solvation shell regions are observed for the Rb(I)-N as well as the Rb(I)-H. The maximum distance of Rb(I)-N in the first solvation shell is in accordance with experimental data where a coordination number of 8 is favorable. A non-single coordination number of the first and second shell indicates dynamic solvation structure. It is confirmed by frequent exchange ligand processes observed within a simulation time of 15 ps. The low stabilization energy of donor acceptor ion-ligand interaction with a small Wiberg bond index affirms that the Rb(I)-NH3 interaction is weak electrostatically.

Ab initio of Quantum Mechanics Charge Field Molecular Dynamic (QMCF-MD) of K(I) ion in liquid ammonia has been studied. A Hartree-Fock level of theory was coupled with LANL2DZ ECP basis set for K(I) ion and DZP (Dunning) for ammonia. Two regions as first and second solvation shell were observed. In the first solvation shell at distance 3.7 (A), K(I) ion was coordinated by four to eight ammonia molecules dominated by K(NH 3 ) 6 + species. Second shell of solvation was ranging between 3.7 A to 7.3 A. Within simulation time of 20 ps, the frequent exchange processes of ligands indicating for a very labile solvation structure. Four mechanism types of ligand exchange between first and second solvation shell were observed. Mean residence time of ligand is less than 2 ps confirming weak in ion-ligand interaction. Evaluation of K(NH 3 ) 6 + using natural bond orbital analysis shows that the Wiberg bond Index is less than 0.05 indicating weak electrostatic interaction of K-N.

The non-sulfide catalysts Co-Mo/USY were prepared with three different methods, i.e. co-impregnation and two sequential impregnation procedures. The phases of the synthesized materials and their composition were characterized with X-ray diffraction. Furthermore, the X-ray diffraction patterns were analyzed using Le Bail methods with Rietica software. Finally, an overview of the substitution effect of cobalt and molybdenum on the metal content and acidity of the catalyst were also investigated.

The preparation and characterization of bimetallic catalysts using impregnation method with a variation of concentration of precursor sequence Co and Mo metal obtained catalyst K 1 [Co (0.018 M) - Mo (0.037 M)/USY]. K 2 [Co (0.026 M) - Mo (0.055 M)/USY], K 3 [Co (0.035 M) - Mo (0.074 M)/USY], K 4 [Co (0.05 M) - Mo (0.11 M )/USY] and K 5 [Co (0.107 M) - Mo (0.22 M)/USY].Character of the catalyst in terms of crystallinity was analyzed by XRD. The result shows that there is no cristalinity damage of USY after impregnation but the amorphous cristalin structure was obtained. Amount of metal content was analyzed by XRF and the catalyst morphology by SEM-EDS. The result shows that the higher the concentration of Co and Mo so that find the higher content of metal in catalyst of the prepared catalyst increase. K 4 shows the best characteristic of catalysts prepared in this research. Analysis of K 4 is proving that Co and Mo are presented in catalyst