Chalkidis Anastasios, Jampaiah Deshetti, Amin Mohamad Hassan, Hartley Patrick G, Sabri Ylias M, Bhargava Suresh K
Centre for Advanced Materials & Industrial Chemistry (CAMIC), School of Science , RMIT University , GPO Box 2476, Melbourne , Victoria 3001 , Australia.
CSIRO Energy , Private Bag 10, Clayton South , Victoria 3169 , Australia.
Langmuir. 2019 Jun 25;35(25):8246-8256. doi: 10.1021/acs.langmuir.9b00835. Epub 2019 Jun 11.
CeO nanoparticle-decorated ?-MnO nanotubes (NTs) were prepared and tested for elemental mercury (Hg) vapor removal in simulated natural gas mixtures at ambient conditions. The composition which had the largest surface area and a relative Ce/Mn atomic weight ratio of around 35% exhibited a maximum Hg uptake capacity exceeding 20 mg?g (2 wt %), as determined from measurements of mercury breakthrough which corresponded to 99.5% Hg removal efficiency over 96 h of exposure. This represents a significant improvement in the activity of pure metal oxides. Most importantly, the composite nanosorbent was repeatedly regenerated at 350 ?C and retained the 0.5% Hg breakthrough threshold. It was projected to be able to sustain 20 regeneration cycles, with the presence of acid gases, CO, and HS, not affecting its performance. This result is particularly important, considering that pure CeO manifests rather poor activity for Hg removal at ambient conditions, and hence, a synergistic effect in the composite nanomaterial was observed. This possibly results from the addition of facile oxygen vacancy formation at ?-MnO NTs and the increased amount of surface-adsorbed oxygen species.
制备了CeO纳米颗粒修饰的β-MnO纳米管（NTs），并在环境条件下对模拟天然气混合物中的元素汞（Hg）蒸气去除进行了测试。通过汞穿透测量确定，具有最大表面积且相对Ce/Mn原子重量比约为35%的组合物表现出超过20 mg·g⁻¹（2 wt%）的最大汞吸附容量，这对应于在96小时暴露期间99.5%的汞去除效率。这代表了纯金属氧化物活性的显著提高。最重要的是，复合纳米吸附剂在350℃下可反复再生，并保持0.5%的汞穿透阈值。预计在存在酸性气体、CO和HS的情况下，它能够维持20次再生循环，且不影响其性能。考虑到纯CeO在环境条件下对汞去除的活性相当差，因此观察到复合纳米材料中的协同效应，这一结果尤为重要。这可能是由于在β-MnO NTs上形成了易于形成的氧空位以及表面吸附氧物种数量的增加。
