Synthesis and Granulation of a 5A Zeolite-Based Molecular Sieve and Adsorption Equilibrium of the Oxidative Coupling of Methane Gases

Abstract

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/m3; and Langmuir surface area, 410.5 m2/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...