SBA-15的疏水改性及其对钴基催化剂费-托合成催化性能的影响

李晓峰; 赵俊秀; 石利红

SBA-15的疏水改性及其对钴基催化剂费-托合成催化性能的影响

1.
太原大学外语师范学院基础部, 山西太原 030012;
2.
山西大学化学化工学院, 山西太原 030006

基金项目: 国家自然科学基金青年项目（21306108）；山西省自然科学基金（2013011009-5）；山西大学第十一期本科生科研训练项目。

详细信息

通讯作者:
石利红，Tel：0351-7010588；Fax：0351-7010688；E-mail：shilihong@sxu.edu.cn。

中图分类号: O643
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- 被引次数: 0
出版历程
- 收稿日期: 2013-11-19
- 修回日期: 2014-01-22
- 刊出日期: 2014-04-30

Hydrophobic modification of SBA-15 and its influence on the properties of cobalt-based catalysts for Fischer-Tropsch synthesis

1.
Department of Basic Courses, Foreign Language Normal College of Taiyuan University, Taiyuan 030012, China;
2.
School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006, China

摘要

摘要: 利用甲硅烷基化作用制得了不同疏水基团（甲基、二甲基和三甲基）改性 SBA-15 载体，采用等体积浸渍法制备了质量分数为 5% 的一系列负载型钴催化剂。结合 BET、FT-IR、²⁹Si CP MAS NMR、XRD和 H₂-TPR 等表征手段，考察了SBA-15疏水改性对钴基催化剂物相结构、还原行为以及费-托合成催化性能的影响。催化剂在固定床反应器中在p=2.0 MPa，t=200~250 ℃，H₂和CO体积比为2和GHSV=1 000 h^-1的条件下进行评价。结果表明，相对于未改性 SBA-15负载钴催化剂，疏水基团改性 SBA-15负载钴催化剂的还原度增加，CO 转化率提高；Co₃O₄晶粒粒径增大，难还原钴物种减少，CH₄选择性降低，C₅₊烃选择性增加。
- 钴催化剂 /
- SBA-15 /
- 疏水改性 /
- 费-托合成
Abstract: SBA-15 supports modified by different hydrophobic reagents (methyltriethoxysilane, dimethyldiethoxysilane and chlorotrimethylsilane) were prepared before the impregnation of cobalt precursor. The effects of hydrophobic modification on the crystallite structure and the reduction behaviors were studied by BET, FT-IR, ²⁹Si CP MAS NMR, XRD, and H₂-TPR. Fischer-Tropsch (F-T) synthesis performances were evaluated in a fixed-bed reactor at 2.0 MPa, 200~250 ℃, H₂/CO (volume ratio)=2, and GHSV=1 000 h^-1. The result indicated that hydrophobic modification led to the increase in reduction degree of the supported cobalt, resulting in the increase of CO conversion of cobalt catalysts for F-T synthesis. Moreover, due to the increase of Co₃O₄ crystallite size and the decrease of un-reducible cobalt compound after hydrophobic modification, CH₄ selectivity decreased and C₅₊ selectivity increased.
- cobalt catalyst /
- SBA-15 /
- hydrophobic modification /
- Fischer-Tropsch synthesis

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参考文献(35)

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