Catalytic conversion of mercury over Ce doped Mn/SAPO-34 catalyst: Sulphur tolerance and SO2/SO3 conversion
Catalytic conversion of mercury over Ce doped Mn/SAPO-34 catalyst: Sulphur tolerance and SO2/SO3 conversion
复制标题
Ce 掺杂 Mn/SAPO-34 催化剂上汞的催化转化：耐硫性和 SO2/SO3 转化
DOI：
10.1016/j.jhazmat.2019.120986
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发表时间：
2020
影响因子：
13.6
通讯作者：
Pan Wei-Ping
中科院分区：
文献类型：
--
作者：
Wang Tao;Liu Jun;Yang Yihuan;Sui Zifeng;Zhang Yongsheng;Wang Jiawei;Pan Wei-Ping
制备了一系列Mn-Ce/SAPO-34催化剂，用于研究单质汞的催化氧化反应。进一步考察了催化剂的耐硫性和SO3生成情况。Hg0由PSA Cavkit提供的压缩空气运送。NO、SO2和NH3是标准气体，H2O是通过载气产生的。添加Ce后，Mn能进入CeO2晶格，形成包覆氧和分散良好的高价锰离子，有利于NO的脱除和HgO的氧化。9 Mn-9Ce催化剂的HgO转化率最高，在50~300 °C范围内，HgO转化率可达92%以上。由于Ce对SO2的高亲和力，加入Ce后的锰基催化剂的抗硫性显著提高，催化剂上HgSO4的相对含量超过72%，与9 Mn相比，9 Mn9Ce催化剂上的SO3生成量降低了17%。H2O不仅降低了SO2的有效活性中心，而且降低了SO2的氧化速率。活性中心优先被NH3占据，而不是Hg0和SO2，产生NH4+占据的阳离子空位。因此，H2O和NH3对HgO转化和SO3生成均有抑制作用。
A series of Mn-Ce/SAPO-34 catalysts were prepared to study the catalytic oxidisation of elemental mercury (Hg0). Sulphur tolerance and SO3formation over the catalyst were studied further. Hg0was transported by compressed air from PSA Cavkit. NO, SO2, and NH3are standard gases, and H2O is produced by gas carrying. Mn could incorporate into the cerium oxide lattice to form capping oxygen and well-dispersed high valance manganese ions after the addition of Ce, which was conducive to NO removal and Hg0oxidisation. 9 Mn-9Ce showed the best performance regarding Hg0conversion, achieving more than 92% Hg0conversion efficiency at 50–300 °C. The sulphur resistance of the Mn-based catalyst was significantly improved after the addition of cerium due to the high affinity of Ce for SO2, and the relative content of HgSO4was exceeded 72% on the 9 Mn-9Ce catalyst with SO2; SO3formation over the 9 Mn-9Ce decreased by 17% compared with the 9 Mn. H2O not only reduced the available active site, but also decreased the oxidation rate of SO2. The active sites were preferentially occupied by NH3rather than Hg0and SO2, generated NH4+occupied cation vacancies. Therefore, both H2O and NH3have inhibitory effects on Hg0conversion and SO3formation.