Use of a Low-Cost Template-Free ZSM-5 for Atmospheric Petroleum Residue Pyrolysis

Abstract

To understand the physicochemical properties and catalytic activity during the pyrolysis of atmospheric petroleum residue, a templatefree ZSM-5 zeolite was synthesized using a direct method without additional seeds or an organic structure director and compared with conventionally synthesized ZSM-5. The crystallinities of the two zeolites were evaluated by XRD and FTIR and were quite similar; however, structural analyses using SEM and argon physisorption revealed that the zeolites diverged in particle diameter and in the external surface area of the micropores. The synthesis procedure without a template incorporated additional aluminum into the crystalline network, according to ICP-AES and TPD NH 3 experiments. The catalytic pyrolysis performed over the template-free ZSM-5 generated results comparable to those for pyrolysis performed over the conventional ZSM-5 according to its hydrocarbon distribution. The selectivity to aromatics compounds was exactly the same for both ZSM-5 zeolites, and these values stand out compared to thermal pyrolysis. The template-free ZSM-5 produced 20% of light hydrocarbons (C 4 -C 6 ), where such compounds are olefins and paraffins of great interest to the petrochemical industry. Therefore, template-free ZSM-5 is promising for industrial use due to its lowered synthesis time, low-cost and significant distribution to light hydrocarbons.

Synergistic Coconversion of Refinery Fuel Oil and Methanol over H-ZSM-5 Catalyst for Enhanced Production of Light Olefins

“…The observed bands at 1160, 1070, 780, 540, and 445.5 cm −1 were attributed to the external asymmetric stretching of AlO 4 and SiO 4 , internal asymmetric stretching of siloxane structures, external symmetric stretching of siloxane groups, structure-sensitive five-membered rings of the pentasil structure, and bending vibrations of the Si−O or Ti−O bonds in the H-ZSM-5 crystal, respectively. 32 Further details of the catalyst properties are presented in the Supporting Information.…”

“…The FTIR spectrum (Figure , the lower panel) exhibited bands at 3370 and 1600 cm –1 , which were assigned, respectively, to the surface-physisorbed siloxane and/or hydroxyl groups and bending vibrations of lattice water molecules. The observed bands at 1160, 1070, 780, 540, and 445.5 cm –1 were attributed to the external asymmetric stretching of AlO 4 and SiO 4 , internal asymmetric stretching of siloxane structures, external symmetric stretching of siloxane groups, structure-sensitive five-membered rings of the pentasil structure, and bending vibrations of the Si–O or Ti–O bonds in the H-ZSM-5 crystal, respectively . Further details of the catalyst properties are presented in the Supporting Information.…”

Catalytic Decomposition of Pyrolysis Fuel Oil over in Situ Carbon-Coated Ferrierite Zeolite for Selective Hydrogen Production

“…The much smaller peak intensity of the C–C carbon peak than that of the CC carbon on the FER(10) revealed less amorphous carbon formations with larger defect sites from the graphitic carbon species as confirmed by Raman analysis. As shown in Supplementary Figure S9, the FT-IR spectra on the fresh FER zeolites showed the characteristic absorption bands for the asymmetric and symmetric stretching bands of the surface siloxane groups appeared at 1220, 1097, and 792 cm –1 and M–O absorption bands at 450 cm –1 without any significant differences on all the FER zeolites . After the decomposition of PFO at 750 °C on the FER zeolites, these characteristic absorption peaks of siloxane groups significantly disappeared on the less active FER(15) and FER(20) zeolites compared with that of FER(10).…”

“…As shown in Supplementary Figure S9, the FT-IR spectra on the fresh FER zeolites showed the characteristic absorption bands for the asymmetric and symmetric stretching bands of the surface siloxane groups appeared at 1220, 1097, and 792 cm −1 and M− O absorption bands at 450 cm −1 without any significant differences on all the FER zeolites. 43 After the decomposition of PFO at 750 °C on the FER zeolites, these characteristic absorption peaks of siloxane groups significantly disappeared on the less active FER (15) and FER(20) zeolites compared with that of FER (10). This observation revealed that the preservations of the siloxane groups even after decomposition of PFO were also important to generate additional active sites originated from the defected crystalline coke precursors on the FER surfaces.…”

Effect of Physicochemical Properties of Co and Mo Modified Natural Sourced Hierarchical ZSM-5 Zeolite Catalysts on Vanillin and Phenol Production from Diphenyl Ether

“…(2) [24] that in angel 2θ = 7-10 0 , 22-25 0 [25,26]. It depicts that the MFI (Mordenite Framework Inverted) as the pentasil framework was successfully synthesized.…”