Probing mesoporous character, desulfurization capability and kinetic mechanism of synergistic stabilizing sorbent CaxCuyMnzOi/MAS-9 in hot coal gas

Abstract

Developing structurally stable sorbents for high-temperature H2S direct removal is recognized as a valuable energy-saving strategy for efficient utilization of hot coal gas (HCG), which depends upon their mesoporous features and desulfurization capabilities. Herein, tailored hierarchical CaxCuyMnzOi/MAS-9 sorbents were fabricated via a facile sol–gel method using high-activity phase CaxCuyMnzOi anchored onto versatile mesoporous MAS-9. After O/S-exchange procedure, noteworthy straight channels of MAS-9 (SBET = 808 m2 g−1) provided enough available spaces for the storage of generative large MeSy nanoparticles, which was better than other conventional zeolites. The probing of variables (i.e. support type, active ingredient, loadings, and sulfidation temperature) on H2S removal revealed that 50%Ca3Cu10Mn87Oi/MAS-9 shared an excellent breakthrough sulfur capacity (171.57 mg g−1) at 800 °C, even it experienced six reusable cycles, due to synergistic stabilizing effect of Ca-Cu-Mn and high-temperature tolerance of SiOAl framework of MAS-9. Especially, CaO dopant endowed the sorbent with superficial alkalinity and high-temperature resistance. The brilliant desulfurization behavior was also described by the fast H2S diffusion or component deactivation vs. duration time on stream according to the followed kinetic investigation. Thus, the refined Ca3Cu10Mn87Oi/MAS-9 possesses the expected representative desulfurization nature and great potentiality for raw HCG in practical applications.