高活性耐硫MoO3改性NiO-Al2O3催化剂用于焦炉煤气甲烷化
Highly active and sulfur-tolerant MoO3 modified NiO-Al2O3 catalysts for coke oven gas methanation
作者单位E-mail
王志斌 太原理工大学化学工程与技术学院, 省部共建煤基能源清洁高效利用国家重点实验室, 太原 030024  
秦志峰 太原理工大学化学工程与技术学院, 省部共建煤基能源清洁高效利用国家重点实验室, 太原 030024
山西浙大新材料与化工研究院, 太原 030002
山西省环境规划院博士后科研工作站, 太原 030002
清华大学环境科学与工程博士后流动站, 北京 100084 
qinzhifeng2022@163.com 
韩勋 太原理工大学化学工程与技术学院, 省部共建煤基能源清洁高效利用国家重点实验室, 太原 030024  
孙鹏程 山西省环境规划院博士后科研工作站, 太原 030002  
刘毅 清华大学环境科学与工程博士后流动站, 北京 100084  
常丽萍 太原理工大学化学工程与技术学院, 省部共建煤基能源清洁高效利用国家重点实验室, 太原 030024  
任军 太原理工大学化学工程与技术学院, 省部共建煤基能源清洁高效利用国家重点实验室, 太原 030024  
李聪明 太原理工大学化学工程与技术学院, 省部共建煤基能源清洁高效利用国家重点实验室, 太原 030024 licongming0523@163.com 
摘要: 采用双水解共沉淀法结合浸渍法合成了系列的MoO3改性的xMoO3/NiO-Al2O3催化剂(x%为MoO3的质量分数),利用固定床装置对催化剂的甲烷化反应活性和耐硫性能进行评价,并对失活前后催化剂进行详细表征。结果表明,随着MoO3含量的升高MoO3改性后的催化剂甲烷化活性有所下降,但MoO3的掺杂显著提升了催化剂的耐硫性能。催化剂低温甲烷化活性降低的原因在于MoO3负载量的增加降低了催化剂的活性比表面积,但MoO3的引入也为硫化物提供了一个竞争吸附位点,进而延缓了活性位点的硫中毒过程。当MoO3负载量(质量分数)为12.5%时,12.5MoO3/NiO-Al2O3催化剂在143 mg·m-3 H2S/H2气氛下运行时间长达7 h,远高于其他催化剂。12.5MoO3/NiO-Al2O3催化剂吸收硫的量(质量分数)达到0.71%,是NiO-Al2O3催化剂硫吸附量的1.48倍。XPS表征进一步发现12.5MoO3/NiO-Al2O3催化剂表面生成的MoS2最多,这说明在此负载量下Mo优先吸附了更多的硫而保护了活性位点。此外,MoO3负载量为12.5%时,MoO3在催化剂表面接近单层分散阀值,当竞争吸附发生时,为硫化物提供更多的吸附位点。
关键词: 焦炉煤气  MoO3/NiO-Al2O3  MoO3改性  耐硫性能
基金项目: 2018年度山西省优秀人才科技创新项目(No.201805D211037)、2016年度山西省科技重大专项(No.MJH2016-03)和山西浙大新材料与化工研究院研发项目(No.2021ST-AT-002)资助。
Abstract: A series of xMoO3/NiO-Al2O3 catalysts (x% represented the mass fraction of MoO3) were prepared by double hydrolytic co-precipitation method combined with impregnation method. The methanation reaction activity and sulfur resistance of catalysts were evaluated using a fixed-bed reactor, and the catalysts were characterized in detail fresh and after deactivation. The results showed that the low-temperature methanation activity of the catalyst decreased with the increase in MoO3 loading, whereas the sulfur resistance of the catalyst was significantly enhanced after MoO3 doping. The decrease in catalyst activity for low-temperature methanation was attributed to the fact that the increase in MoO3 loading reduced the active specific surface area of the catalyst, but the introduction of MoO3 also provided a competitive adsorption site for sulfide, which can delay sulfur poisoning at the active site. The xMoO3/NiO-Al2O3 catalyst with 12.5% MoO3 loading (mass fraction) maintained the highest methanation activity for 7 h in the presence of 143 mg·m-3 H2S/H2 (81.1% CO conversion, 550℃). The sulfur chemisorption content of 12.5MoO3/NiO-Al2O3 catalyst reaching 0.71% (mass fraction) was 1.48 times that of NiO-Al2O3 catalyst and further XPS also confirmed that the amount of MoS2 generated was the highest, which indicated that Mo preferentially adsorbs more sulfur and protects the active site. In addition, at a MoO3 loading of 12.5%, MoO3 on the surface of the catalyst reached the threshold of monolayer dispersion, which can provide more adsorption sites for sulfides when competitive adsorption occurs.
Keywords: coke oven gas  MoO3/NiO-Al2O3  MoO3 modification  sulfur resistance
投稿时间:2022-12-06 修订日期:2023-04-01
摘要点击次数:  854
全文下载次数:  473
王志斌,秦志峰,韩勋,孙鹏程,刘毅,常丽萍,任军,李聪明.高活性耐硫MoO3改性NiO-Al2O3催化剂用于焦炉煤气甲烷化[J].无机化学学报,2023,39(5):967-978.
查看全文  查看/发表评论  下载PDF阅读器
Support information: