New insights into the morphological effects of MnOx-CeOx binary mixed oxides on Hg0 capture

In this study, the morphological effects of MnOx-CeOx adsorbents on their Hg0 elimination performance were investigated. The sample with a virgin nanorod microtopography performed significantly better than the nanocube-containing counterparts; in the whole temperature range investigated, a Hg0 removal efficiency of-97% was maintained. The microstructure of virgin nanorods possessed a high specific surface area, meaning that the interactions between Hg0 and adsorbent surface active sites would be encouraged. Furthermore, the strong acidity and oxidizability would facilitate the adsorption of Hg0 and the oxidation of the adsorbed Hg0 to HgO, which finally contributed to a superior Hg0 capture ability. During the entire Hg0 capture cycles, only Mn4+ and chemisorbed oxygen operated as the active sites in oxidizing Hg0 to HgO over the nanorod-containing MnOx- CeOx samples, whereas Ce4+ joined the active species group to oxidize Hg0 for the MnOx-CeOx with a virgin nanocube, despite its limited activity. Such knowledge demonstrated that morphology control of the adsorbents at the nanometer level could significantly increase their activity.

Automated summary

The study investigated the morphological effects of MnOx-CeOx adsorbents on their Hg0 elimination performance. The sample with a virgin nanorod microtopography performed significantly better than the nanocube-containing counterparts, maintaining a Hg0 removal efficiency of -97% in the entire temperature range. The microstructure of virgin nanorods possessed a high specific surface area, promoting the interactions between Hg0 and adsorbent surface active sites.