Controllable fabrication of persimmon wood-inspired macroporous (a%Co-Mn)1.5Al0.5Ox, high desulfurization performance and analysis of deactivation kinetic mechanism

Abstract

The removal of H2S that seriously threaten the environment and human health is of great significance in enhancing coal cleaning utilization. Herein, a series of persimmon wood-inspired macroporous (a%Co-Mn)1.5Al0.5Ox (a = 0, 3, 6, 10, 15, 20) sorbents were constructed by the self-assembly of vacuum-assisted sol–gel procedure, and their desulfurization efficiency was evaluated on a fixed-bed reactor at 600–800 °C. Among cobalt-doping sorbents, the breakthrough sulfur capacity (BSC, 272.2 mg g−1) and effective utilization (EU, 81.5%) over (15%Co-Mn)1.5Al0.5Ox is greatly high than the value (138.08 mg g−1) over ZnCoO4/SAPO-34@SBA-15, and slightly lower than BSC (286.2 mg g−1) and EU (92.3%). The magnification SEM images of (15%Co-Mn)1.5Al0.5Ox revealed that regularly straight macroporous channel structure inherited from persimmon wood effectively promoted the rapid diffusion of H2S molecules and accelerated the rate of sulfur/oxygen exchange on the interface of the channel wall. In the meantime, the results studied by the deactivation kinetics model also confirm invariable rate constants (ka, kd) with high correlation coefficients due to higher stability and renewable ability of (15%Co-Mn)1.5Al0.5Ox.