Improvement of NO adsorptive selectivity by the embedding of Rh in MOF‐177 as carrier

Abstract

In this paper, MOF‐177 was embedded with Rh for the improvement of NO adsorptive selectivity at room temperature. The results showed that the experimental NO saturated adsorption capacity of MOF‐177 was very limited value of 1.35 mL·g−1 with a negligible selectivity, but the embedded 3 wt % Rh/MOF‐177 improved it to 16 mL·g−1 with higher maximal selectivity of NO to CO2 (352) and to O2 (600) under low partial pressure. In the simulated mixture gas, the adsorption capacity of NO atmosphere was about 9–18 times higher than that of O2 and CO2, and the adsorptive selectivity was up to near 18. The reductive Rh particles in MOF‐177 were basically nanometer‐sized higher dispersion state by great carrier function of MOF‐177. The pulse adsorption experiments verified that one reduced Rh0 adsorbed three NO molecules, indicating that the NO adsorption form in Rh/MOF‐177 should be a trinitro‐group (Rh (NO)3) adsorbed species in low pressure. This work firstly illustrated that the MOFs materials embedded with metal particle such as Rh can obviously improve NO adsorption selectivity and also provided a reference way for functionalized modification of MOFs materials to enhance the adsorptive separation performance of pollutant NO in flue gas.