Influence of alkali metal modification and reaction conditions on the catalytic activity and stability of Ni containing smectite-type material for steam reforming of acetic acid
Influence of alkali metal modification and reaction conditions on the catalytic activity and stability of Ni containing smectite-type material for steam reforming of acetic acid
复制标题
DOI：
10.1016/j.ijhydene.2011.01.155
复制
发表时间：
2011-05-01
影响因子：
7.2
通讯作者：
Arai, Masahiko
中科院分区：
文献类型：
--
作者：
Iwasa, Nobuhiro;Yamane, Toshiyuki;Arai, Masahiko
采用Li、Na、K、Rb、Cs等碱金属对Ni掺杂的蒙脱石类介孔材料SM（Ni）进行改性，并以乙酸为模型化合物，对生物质热解生物油水相进行水蒸气重整反应。乙酸的初始转化率和产生的H-2的浓度通过用这些碱金属改性而显著提高。1.0 wt%K改性的SM（Ni）催化剂在所测试的改性SM（Ni）材料中表现出最高的活性。此外，K促进了蒙脱石中的Ni物种的还原，产生比原始SM（Ni）样品中更多的金属Ni物种。因此，与原始蒙脱石催化剂相比，K改性的SM（Ni）催化剂具有更高的初始活性。然而，这些改性材料在反应过程中由于在其表面上的碳沉积而失去其活性，类似于原始SM（Ni）。考察了O-2或H-2的加入量、水碳比（S/C）和反应温度对反应的影响。在973 K的高温下，S/C比为3.3时，未改性的SM（Ni）催化剂获得了更高和更稳定的活性。版权所有（C）2011，氢能出版有限责任公司。由爱思唯尔有限公司出版。保留所有权利。
A Ni incorporated mesoporous smectite-like material, SM(Ni), was modified by various alkali metals, such as, Li, Na, K, Rb or Cs, and tested for the steam reforming of acetic acid as a model compound of aqueous phase of bio-oil derived from biomass pyrolysis. Initial conversion of acetic acid and concentration of H-2 produced are drastically enhanced by the modification with these alkali metals. 1.0 wt% K-modified SM(Ni) catalyst exhibits the highest activity among the modified SM(Ni) materials tested. Addition of K promotes the reduction of Ni species incorporated in the smectite, yielding more metallic Ni species than in the original SM(Ni) sample. Therefore, the K-modified SM(Ni) catalyst gives higher initial activity compared with the original smectite catalyst. However, these modified materials lose their activities due to carbon deposition on their surface during the course of reaction, similar to the original SM(Ni). The influence of reaction conditions, such as O-2 or H-2 addition, steam to carbon ratio (S/C) and reaction temperature, was also investigated. Higher and more stable activity was obtained with unmodified SM(Ni) catalyst at a high reaction temperature of 973 K and at an S/C ratio of 3.3. Copyright (C) 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.