重整催化剂的抗硫性能研究进展

doi:10.11949/0438-1157.20200547

摘要/Abstract

摘要：

基于固体氧化物燃料电池(SOFC)的烃类原位重整供氢技术是重要的分布式和小型化制氢方案。传统镍基重整催化剂在烃类重整过程中，原料中微量的硫化物即可使催化剂中毒失活，严重时还可能造成巨大的安全隐患。本文梳理总结了催化剂硫中毒的机理，简述了天然气、液化石油气、液态烃重整原料中硫化物的组成和含量，重点分析了已报道的用于重整反应的抗硫催化剂并总结了有效可行的催化剂抗硫方案，并从重整制氢催化剂的硫中毒机理指导高效抗硫催化剂的开发。最后，文章指出，重整催化综合性能的提升、重整原料的预处理和重整反应器设计等综合抗硫策略也是重要的研究方向。

关键词: 氢气, 烃类重整, 催化剂, 硫中毒, SOFC

Abstract:

Hydrocarbon in-situ reforming hydrogen supply technology based on solid oxide fuel cell (SOFC) is an important distributed and miniaturized hydrogen production solution. Traditional nickel-based reforming catalysts often face sulfur poisoning during the reaction with trace amount of sulfur in the feedstock. In some cases, the existing sulfur may even cause severe safety risks. In this paper, the mechanisms of sulfur poisoning are summarized; the compositions and contents of sulfur species in natural gas, liquefied petroleum gas and liquid hydrocarbon are briefly described; the reported sulfur resistant catalysts for different reforming reactions are reviewed, and the effective and feasible solutions for developing sulfur-tolerant catalysts are summarized. The mechanisms of sulfur poisoning could guide the design of sulfur-resistant reforming catalyst with high performance. Finally, the paper reveals that the improvement of catalytic overall performance, the pretreatment of reforming feedstock and the design of reforming reactor and other comprehensive anti-sulfur strategies are also important research directions.

Key words: hydrogen, hydrocarbon reforming, catalysts, sulfur poisoning, SOFC

中图分类号:

TQ 426.8

孙克宁, 陈谦, 聂明明, 侯瑞君. 重整催化剂的抗硫性能研究进展[J]. 化工学报, 2020, 71(9): 4131-4140.

Kening SUN, Qian CHEN, Mingming NIE, Ruijun HOU. Progress in the sulfur resistance of reforming catalysts[J]. CIESC Journal, 2020, 71(9): 4131-4140.

图/表 3

图1 Ni基重整催化剂主要的硫中毒机理

Fig.1 Sulfur poisoning mechanism over the Ni-based catalyst

图2 Rh、Ni、Rh2Ni1、Rh1Ni2表面上四种基本丙烷蒸汽重整路径活化能垒的比较[32]

Fig.2 Comparison of activation barriers across surfaces of Rh, Ni, Rh2Ni1 and Rh1Ni2 for four elementary propane steam reforming paths[32]

表1 H2S、S在Ni和Ni-M合金表面的吸附能

Table 1 Adsorption energies of H2S, S on the Ni and M/Ni surfaces

金属	吸附能/eV
金属	H₂S	S
Ni	-0.95	-5.62
Ni-Cu	-0.94	-5.68
Ni-Ag	-0.57	-5.04
Ni-Au	-0.75	-4.63
Ni-Rh	-1.03	-5.38
Ni-Pd	-0.88	-5.30
Ni-Pt	-0.82	-4.98

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