Cu incorporating into OMS-2 lattice creates an efficient Hg0 removal sorbent in natural gas with ambient-temperature H2S/H2O tolerance

Abstract

Removing mercury in wet natural gas containing acidic components is essential to developing the natural gas purification industry and mitigating corrosion in aluminum heat exchangers. In this work, the Cu-doped manganese oxide octahedral molecular sieve (OMS-2) nanorods were designed for oxidation of Hg0 in wet natural gas. The Hg0 removal efficiency over Cu(0.05)-OMS-2 reached 98.2 % under a high space velocity of 24 × 104 h−1 and a complex atmosphere containing H2O, CO2, and H2S. Surface reactive oxygen species produced by strong electronic interactions owing to Mn-O-Cu hybridization was the main active sites for Hg0 oxidation. The reactive oxygen species on Cu(0.05)-OMS-2 reacted with H2S to form active sulfur species, which could combine with Hg0 to form HgS. Cu(0.05)-OMS-2 exhibited excellent ambient-temperature water resistance, which was attributed to the good redox properties caused by Cu incorporation. This work provided a new strategy for designing efficient sorbents to remove Hg0 from wet natural gas.