...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Fuel >Preparation and characterization of Al_2O_3-MgO catalytic supports modified with lithium
【24h】

Preparation and characterization of Al_2O_3-MgO catalytic supports modified with lithium

机译：锂改性Al_2O_3-MgO催化载体的制备与表征

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Al_2O_3-MgO catalytic supports were modified with different amounts of lithium in order to obtain novel Al_2O_3-MgO-Li(x) formulations containing basic sites. The basic sites on samples surface were identified and quantified through CO_2 chemisorptions. It was found that total amount of basic sites increases as the Li content increases. The Li identification and its content were performed through Non-Rutherford Back-scattering Spectroscopy (NRBS). The Li addition to the supports produce surface morphological changes as was observed with Scanning Electron Microscopy (SEM). The addition of lithium produces a decrease in specific surface area, changing the textural properties as N_2-physisorption measurements reveal. Structural characterization by X-ray diffraction (XRD) suggests that Li addition changes the crystalline structure of Al_2O_3 from the γ to the δ phase; additionally, this technique indicate the presence of Li_2CO_3, which could be attributed to the preferential reaction of Li with environmental CO_2. It was not found evidence of magnesium carbonates in the fresh samples by XRD. Raman spectroscopy shows bands attributed to the lithium carbonates species corroborating the found by XRD. The obtained results suggest that these materials could be potentially attractive as catalytic supports for reactions where the basic sites are useful such as selective hydrodesulphurization.
机译：用不同量的锂修饰Al_2O_3-MgO催化载体，以获得含有碱性位点的新型Al_2O_3-MgO-Li（x）配方。通过CO_2化学吸附鉴定并定量了样品表面的基本位点。发现随着Li含量的增加，碱性位点的总量增加。 Li的鉴定及其含量是通过非卢瑟福背散射光谱法（NRBS）进行的。如通过扫描电子显微镜（SEM）观察到的，向载体中添加的Li产生表面形态变化。锂的添加会导致比表面积的减少，并随着N_2-物理吸附量的测量而改变织构性质。 X射线衍射（XRD）的结构表征表明，添加Li会改变Al_2O_3的晶体结构，从γ相变为δ相。此外，该技术表明存在Li_2CO_3，这可能归因于Li与环境CO_2的优先反应。 XRD未发现新鲜样品中存在碳酸镁的证据。拉曼光谱表明，归因于碳酸锂物质的谱带证实了XRD的发现。所获得的结果表明，这些材料作为催化载体，对于碱性位点有用的反应（如选择性加氢脱硫）可能具有吸引力。

著录项

  • 来源
    《Fuel》 |2013年第8期|278-285|共8页
  • 作者

    L. Escobar-Alarcon; T. Klimova; J. Escobar-Aguilar; S. Romero; C. Morales-Ramirez; D. Solis-Casados;

  • 作者单位

    Departamento de Fisica, Institute National de Investigations Nucleares, Apdo. Postal 18-1027, Mexico D.F. 11801, Mexico;

    Facultad de Quimica, Departamento de Ingenieria Quimica, UNAM, Ciudad Universitaria, Mexico D.F. 04510, Mexico;

    Instituto Mexicano del Petroleo, Eje Central Ldzaro Cardenas None 152, Col. San Bartolo Atepehuacan, Mexico D.F. 07730, Mexico;

    Departamento de Fisica, Institute National de Investigations Nucleares, Apdo. Postal 18-1027, Mexico D.F. 11801, Mexico;

    Programa de Maestria en Ciencia de Materiales, Facultad de Quimica UAEMex, Mexico,Centra Conjunto de Investigation en Quimica Sustentable UAEM-UNAM, Carretera Toluca-Atlacomulco Km 14.5, C. P. 50200 Toluca, Estado de Mexico, Mexico;

    Centra Conjunto de Investigation en Quimica Sustentable UAEM-UNAM, Carretera Toluca-Atlacomulco Km 14.5, C. P. 50200 Toluca, Estado de Mexico, Mexico;

  • 收录信息 美国《科学引文索引》(SCI);美国《工程索引》(EI);
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

    Catalytic supports; Al_2O_3-MgO; Basic sites; Textural properties;

    机译：催化载体;Al_2O_3-MgO;基本站点;质地特性;

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号