Efficient recovery of hydrogen and sulfur resources over non-sulfide based LaFexAl12-xO19 hexaaluminate catalysts by H2S catalytic decomposition
Efficient recovery of hydrogen and sulfur resources over non-sulfide based LaFexAl12-xO19 hexaaluminate catalysts by H2S catalytic decomposition
复制标题
非硫化物基LaFexAl12-xO19六铝酸盐催化剂通过H2S催化分解高效回收氢和硫资源
DOI：
10.1016/j.apcatb.2019.118354
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发表时间：
2020-04-01
影响因子：
22.1
通讯作者：
Lin, Caihong
中科院分区：
文献类型：
--
作者：
Jiang, Guoxia;Zhang, Xin;Lin, Caihong
炼油厂加氢脱硫后硫化氢（H2S）含量可达20- 100%，从酸性气体中同时回收氢硫资源越来越具有吸引力。目前，H2S分解技术的广泛应用主要受到800℃时氢硫产率低（20%）的限制。本文首次采用一种新型的非硫化物基LaFexAl12-xO19六铝酸盐催化剂，在800℃时氢产率高（50%），同时通过各种表征技术证实了活性相和反应机理。XRD、Raman、XPS、Mossbauer和XAFS结果验证了六铝酸盐结构中的Fe，特别是八面体配位Fe3+是主要的活性相。用密度泛函理论（DFT）验证了H2S分解的反应途径和机理。H2S首先吸附在活性位点上，然后通过直接脱氢机理完成分解。简而言之，目前的研究已经将工业规模分解H2S的挑战降到最低。预计我们的研究结果将为H2S分解技术提供潜在的应用前景。
Simultaneous recovery of hydrogen and sulfur resources from acidic gas hydrogen sulfide (H2S), whose content may reach 20-100 % after hydrodesulfurization in oil refineries, is increasingly attractive. Nowadays, the widespread utilization of H2S decomposition technology is mainly restricted by the low hydrogen and sulfur yield, i.e. 20 % at 800 degrees C. In this work, for the first time a novel non-sulfide based LaFexAl12-xO19 hexaaluminate catalysts was used for high (50 %) hydrogen yield at 800 degrees C. At the same time, the active phases and reaction mechanism were confirmed by various characterization techniques. The XRD, Raman, XPS, Mossbauer and XAFS results verified that the Fe species in the hexaaluminate structure, especially octahedral-coordinated Fe3+, served as the main active phases. The reaction routes/mechanism for H2S decomposition were also verified by density functional theory (DFT) method. H2S was firstly adsorbed on the active sites and then completed the decomposition by direct dehydrogenation mechanism. Briefly, current study has minimized the challenges for H2S decomposition at industrial scale. It is anticipated that our findings will offer potential application of H2S decomposing technology.