This work presents a detailed description of the synthesis of a 5A zeolite and its further granulation into molecular sieve beads. The XRD spectrum of synthesized crystals showed the characteristic peaks of a type A sodium zeolite, and XRF results of the ion-exchanged material with a calcium chloride solution allowed us to verify the formation of a 5A zeolite structure. The analysis of SEM images indicated that the granulated process generated a core−shell structure with suitable mechanical properties for industrial use. The granulated material exhibited similar properties (roundness, 96%; crush strength, 57 N; packing density, 607 kg/m 3 ; and Langmuir surface area, 410.5 m 2 /g) to most commercial molecular sieves. However, its lower water sorption capacity (0.142 kg/kg) reveals that zeolite adsorption is affected by the cementing material. Adsorption equilibrium studies at different temperatures with oxidative coupling of methane (OCM) effluent gases indicated that the material showed a higher affinity for CO 2 , followed by ethylene, ethane, and methane, whereas nitrogen was barely retained. The affinity trend was in agreement with the observed heats of adsorption, which were in the range of 13−30 kJ/mol for tested gases. Isotherms were fitted with a Langmuir model, and adsorption parameters were obtained. Regressed equilibrium equations can be used for further modeling of a swing adsorption separation for OCM effluent gases.

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