物理化学学报 >> 2011, Vol. 27 >> Issue (07): 1743-1750.doi: 10.3866/PKU.WHXB20110711

催化和表面科学 上一篇    下一篇

介孔型铝酸镍纳米棒的制备及其催化氢化裂解甲苯性能

申杉杉, 陆文聪, 张良苗, 岳宝华, 韩玲, 张浩   

  1. 上海大学化学系, 上海 200444
  • 收稿日期:2011-02-23 修回日期:2011-05-05 发布日期:2011-06-28
  • 通讯作者: 陆文聪 E-mail:wclu@shu.edu.cn
  • 基金资助:

    国家自然科学基金(20973108), 上海教委(11ZZ83), 上海市重点学科建设 (J50101)和上海大学创新基金(A.10-0101-09-023)资助项目

Fabrication of Mesoporous NiAl2O4 Nanorods and Their Catalytic Properties for Toluene Hydrocracking

SHEN Shan-Shan, LU Wen-Cong, ZHANG Liang-Miao, YUE Bao-Hua, HAN Ling, ZHANG Hao   

  1. Department of Chemistry, Shanghai University, Shanghai 200444, P. R. China
  • Received:2011-02-23 Revised:2011-05-05 Published:2011-06-28
  • Contact: LU Wen-Cong E-mail:wclu@shu.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (20973108), Shanghai Education Committee, China (11ZZ83), Shanghai Leading Academic Discipline Project, China (J50101), and Innovation Fund of Shanghai University, China (A.10-0101-09-023).

摘要:

以NH4HCO3为造孔剂通过一步水热法成功合成了介孔型单晶NiAl2O4纳米棒, 并考察了不同反应条件对NiAl2O4形貌的影响. 实验结果表明反应时间、反应物浓度、NH4HCO3加入量对产物形貌具有关键作用. 用透射电子显微镜(TEM), 高分辨透射电子显微镜(HRTEM), 扫描电子显微镜(SEM)和X射线衍射仪(XRD)对NiAl2O4纳米棒的形貌、结构和组成进行表征, 并用氮气吸附-脱附法对其比表面积和孔径分布进行了研究. 以介孔型NiAl2O4纳米棒为催化剂, 在固定床反应器上对甲苯进行催化实验, 结果表明当水炭摩尔比为1.0、反应温度为700 ℃时, 400 min反应时间内甲苯平均转化率高达86.5%, 并具有较好的反应稳定性. 比较了直接沉淀法制备的纳米颗粒作为催化剂在甲苯氢化催化裂解中的催化性能. 结果表明水热法制备的棒状NiAl2O4催化剂比不用水热制备的催化剂催化活性要好. 初步探讨了介孔型NiAl2O4纳米棒的可能形成机理.

关键词: 水热法, 单晶NiAl2O4, NH4HCO3, 镍基催化剂, 表征

Abstract:

Mesoporous single-crystalline NiAl2O4 nanorods were successfully synthesized by a one-step hydrothermal method using a pore-forming agent (NH4HCO3). A series of controlled experiments were also carried out to better understand the formation mechanism of NiAl2O4 nanorods. The experimental results indicate that the reaction time, reactant concentration and the amount of NH4HCO3 play an important role in determining the morphology. The morphology, structure and composition of the nanorods were investigated using transmission electron microscopy, high resolution transmission electron microscopy, scanning electron microscopy and X-ray diffraction. The specific surface area and pore-size distribution of the obtained product was determined by nitrogen adsorption-desorption measurements. NiAl2O4 nanorods have a high Brunauer-Emmett-Teller surface area and good porosity properties. The catalytic performance of the NiAl2O4 nanorods during toluene hydrocracking was investigated using a fixed bed reactor. After the toluene catalytic reactions over 400 min at a water stream/carbon molar ratio (H2O/C) of 1.0 with a reaction temperature of 700 ℃ the average conversion efficiency of toluene was about 86.5%. Compared to the NiAl2O4 nanoparticles prepared by alkaline precipitation, the mesoporous NiAl2O4 nanorods exhibited higher catalytic activity and stability during toluene hydrocracking. A possible formation mechanism for the mesoporous NiAl2O4 nanorods is proposed and discussed.

Key words: Hydrothermal method, Single-crystalline NiAl2O4, NH4HCO3, Nickel catalyst, Characterization

MSC2000: 

  • O641