AMn2O4 (A=Cu, Ni and Zn) sorbents coupling high adsorption and regeneration performance for elemental mercury removal from syngas.
AMn2O4 (A=Cu, Ni and Zn) sorbents coupling high adsorption and regeneration performance for elemental mercury removal from syngas.
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DOI：
10.1016/j.jhazmat.2019.121738
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发表时间：
2019-11
影响因子：
13.6
通讯作者：
Zhen Wang;Jing Liu;Yingju Yang;Yingni Yu;Xuchen Yan;Zhen Zhang
中科院分区：
文献类型：
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作者：
Zhen Wang;Jing Liu;Yingju Yang;Yingni Yu;Xuchen Yan;Zhen Zhang
采用低温溶胶-凝胶自燃烧法合成了AMn2O4（A= Cu， Ni和Zn）尖晶石吸附剂，首次用于合成气中单质汞（Hg0）的去除。在模拟合成气条件下，cumn2o4吸附剂对hg0的吸附性能最高，在200 °C条件下，吸附效率达到95%以上。吸附再生实验表明，cumn2o4具有良好的再生性能。考察了合成气组分对cumn2o4上hg0去除的影响。H2S对合成气中hg0的脱除起着最重要的作用，H2S可以吸附在cumn2o4表面，转化为活性硫种与hg0反应形成表面键合的HgS。x射线光电子能谱（XPS）和程序升温解吸（TPD）实验证明，HgS是在废吸附剂上形成的。表面Cu2+阳离子和化学吸附/晶格氧参与hg0的吸附和转化。HCl通过形成表面活性氯来促进hg0的去除。H2、CO和H2O抑制n2气氛下hg0的脱除。然而，在H2S的辅助下，它们对hg0的去除没有明显的影响。cumn2o4优异的捕集hg0性能、良好的再生性能和耐水性能使其成为合成气中高温脱除hg0的吸附剂。
AMn2O4(A= Cu, Ni and Zn) spinel sorbents synthesized by a low-temperature sol-gel auto-combustion method were for the first time used to eliminate elemental mercury (Hg0) from syngas. CuMn2O4sorbent exhibits the highest Hg0adsorption performance under simulated syngas, higher than 95 % Hg0capture efficiency is obtained at 200 °C. Adsorption-regeneration experiments demonstrate that the regenerability of CuMn2O4is excellent. The influences of syngas compositions on Hg0elimination over CuMn2O4were examined. H2S plays the most important role in Hg0removal from syngas, which can be adsorbed on CuMn2O4surface and transformed into active sulfur species to react with Hg0to form surface-bonded HgS. X-ray photoelectron spectroscopy (XPS) and temperature-programmed desorption (TPD) experiments prove that HgS is formed on the spent sorbent. The surface Cu2+cations and chemisorbed/lattice oxygens participate in Hg0adsorption and transformation. HCl promotes Hg0removal by forming surface active chlorine species. H2, CO, and H2O inhibit Hg0removal under N2atmosphere. However, they exhibit no obvious effect on Hg0removal with the assistance of H2S. The excellent Hg0capture performance, good regenerability and H2O resistance of CuMn2O4make it to be a very promising sorbent for Hg0removal from syngas at higher temperature.