基于负载在铝柱撑层状黏土上的铁和钴的双金属催化剂：SCR-CH的制备、反应活性及机理

Bimetal catalyst based on Fe and Co supported on Al pillared interlayer clays: Preparation, reactivity and mechanism for SCR-CH.

作者信息

Ning Shuying, Huang Shasha, Yang Honghai, Zhao Bingtao, Su Yaxin

机构信息

School of Environmental Science and Engineering, Donghua University, Shanghai 201620, China.

School of Energy and Power Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China.

出版信息

iScience. 2023 Jul 20;26(8):107432. doi: 10.1016/j.isci.2023.107432. eCollection 2023 Aug 18.

DOI:10.1016/j.isci.2023.107432

PMID:37575191

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC10415785/

Abstract

Montmorillonite was used as raw clay to prepare the Al-pillared interlayer clay (Al-PILC) as support by impregnation methods. Co and Fe were loaded in series on Al-PILC to prepare the bimetal catalysts (Fe-Co/Al-PILC). The SCR-CH was evaluated in a fixed bed reactor and the results indicated that 0.27Fe-Co/Al-PILC exhibited 100% N selectivity and above 63% NO conversion in the presence of 10% HO, and the introduction of Fe significantly improved the Co/Al-PILC catalyst's resistance to HO and SO. Characterization showed that Lewis and Brønsted acids co-existed on the catalyst surface, and the Lewis acid was the dominant active acid site and enhanced the activation of methane over the 0.27Fe-Co/Al-PILC. Fe promoted the formation of isolated Co and CoO species, and the isolated Fe particles improved CH-SCR performance. The reaction route was proposed based on DRIFTS tests and the active intermediates were mainly various nitrates and nitromethane (CHNO).

摘要

以蒙脱石为原料黏土，通过浸渍法制备铝柱撑黏土（Al-PILC）作为载体。将Co和Fe依次负载在Al-PILC上制备双金属催化剂（Fe-Co/Al-PILC）。在固定床反应器中对SCR-CH进行了评估，结果表明，在10% H₂O存在的情况下，0.27Fe-Co/Al-PILC表现出100%的N₂选择性和63%以上的NO转化率，并且Fe的引入显著提高了Co/Al-PILC催化剂对H₂O和SO₂的抗性。表征表明，催化剂表面同时存在Lewis酸和Brønsted酸，且Lewis酸是主要的活性酸位点，增强了0.27Fe-Co/Al-PILC上甲烷的活化。Fe促进了孤立Co和CoO物种的形成，孤立的Fe颗粒改善了CH-SCR性能。基于漫反射红外傅里叶变换光谱（DRIFTS）测试提出了反应路线，活性中间体主要是各种硝酸盐和硝基甲烷（CH₃NO₂）。