• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文会议>AIChE Annual Meeting >Na - promoted Pt catalysts in core - shell structure for the low - temperature Water-Gas-Shift reaction
【24h】

Na - promoted Pt catalysts in core - shell structure for the low - temperature Water-Gas-Shift reaction

机译：低温水煤气变换反应核心壳结构的Na促进的Pt催化剂

获取原文
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The water - gas - shift (WGS) reaction is a key step in high - purity hydrogen production. Platinum- based catalysts are active over a wide temperature range and can be stabilized on certain supports, such as ceria and zirconia during WGS operation cycles. Thus, Pt is a good albeit much costlier alternative to Cu - ZnO catalysts for the demanding application to fuel cell systems. The activity of Pt on reducible ceria for low - temperature applications has been attributed to the interaction of Pt with the support and nanoscale ceria with a lot of surface oxygen defects is superior to high - temperature annealed ceria of large crystal size and low defect concentration ~(1, 2). Addition of alkali was recently reported to promote the WGS activity of Pt on reducible oxide supports ~3, and very recently our group reported that alkali promotion of Pt is possible even on an inert oxide surface such as silica ~4. Moreover, a very small amount of oxidized Pt, atomically dispersed and stabilized by the alkali, Na- O-Pt(OH) _x, appeared to contain the active sites. From the practical viewpoint, this is important as it allows the choice of a low-cost support, e. g. silica or alumina for low - temperature shift applications. It also allows one to design a catalyst with potentially trace amounts of the costly Pt metal. From a fundamental viewpoint, understanding the promotion would shed light on the mechanistic aspects and allow rational designs of new WGS catalysts using very small amounts of Pt.
机译：水 - 煤气变换（WGS）反应是高纯度氢气产生的关键步骤。基于铂的催化剂在宽温度范围内活性，并且在WGS操作循环期间可以在某些载体上稳定在某些载体上，例如Ceria和氧化锆。因此，Pt是一种很好的昂贵的Cu - ZnO催化剂，用于苛刻应用于燃料电池系统。 Pt在低温应用中的可减少二氧化铈的活性归因于PT与载体的相互作用和纳米级氧气缺氧的纳米级缺氧优于高温退火的大晶体尺寸和低缺陷浓度〜 （1,2）。最近据报道，添加碱以促进PT的WGS活性在可还原氧化物载体上〜3，并且最近我们的本组甚至在惰性氧化物表面如二氧化硅表面上的氧化物表面促进Pt的碱性促进。此外，通过碱金属Na-O-Pt（OH）_X的非常少量的氧化Pt，原子分散和稳定，似乎含有活性位点。从实际的观点来看，这很重要，因为它允许选择低成本支持，即G。二氧化硅或氧化铝用于低温换档应用。它还允许人们设计具有潜在痕量的昂贵的Pt金属的催化剂。从基本的观点来看，了解促销将在机械方面阐明，并使用非常少量的Pt允许新的WGS催化剂的合理设计。

著录项

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