Mg-Al-hydrotalcite with alkaline sites protects Ni/KIT-6 from formation of amorphous coke in glycerol steam reforming via tailoring reaction intermediates
作者机构:School of Material Science and EngineeringUniversity of JinanJinan 250022China Joint International Research Laboratory of Biomass Energy and MaterialsCollege of Materials Science and EngineeringNanjing Forestry UniversityNanjing 210037China State Key Laboratory of Coal CombustionHuazhong University of Science and TechnologyWuhan 430074China
出 版 物:《Frontiers of Chemical Science and Engineering》 (化学科学与工程前沿(英文版))
年 卷 期:2024年第18卷第4期
页 面:25-39页
核心收录:
学科分类:081702[工学-化学工艺] 081705[工学-工业催化] 08[工学] 0817[工学-化学工程与技术] 080502[工学-材料学] 0805[工学-材料科学与工程(可授工学、理学学位)]
基 金:supported by the National Natural Science Foundation of China(Grant No.52276195) the Program for Supporting Innovative Research of Jinan(Grant No.202228072) the Program for Agricultural Development of Shandong(Grant No.SD2019NJ015)
主 题:steam reforming of glycerol Mg-Alhydrotalcite sacrificial catalyst reaction intermediates property of coke
摘 要:During steam reforming,the performance of a catalyst and amount/property of coke are closely related to reaction intermediates reaching surface of a ***,modification of reaction intermediates by placing Mg-Al-hydrotalcite above Ni/KIT-6 catalyst in steam reforming of glycerol was conducted at 300 to 600°*** results revealed that the catalytic activity of Ni/KIT-6 in the lower bed was enhanced with either Mg1-Al5-hydrotalcite(containing more acidic sites)or Mg5-Al1-hydrotalcite(containing more alkaline sites)as upper-layer *** in situ infrared characterization of steam reforming demonstrated that Mg-Al-hydrotalcite catalyzed the deoxygenation of glycerol,facilitating the reforming of the partially deoxygenated intermediates over Ni/***-Al-hydrotalcite as protective catalyst,however,did not protect the Ni/KIT-6 from formation of more ***,this did not lead to further deactivation of Ni/KIT-6 while Mg5-Al1-hydrotalcite even substantially enhanced the catalytic stability,even though the coke was much more significant than that in the use of single Ni/KIT-6(52.7%vs.28.6%).The reason beneath this was change of the property of coke from more aliphatic to more ***5-Al1-hydrotalcite catalyzed dehydration of glycerol,producing dominantly reaction intermediates bearing C=C,which formed the catalytic coke of with carbon nanotube as the main form with smooth outer walls as well as higher aromaticity,C/H ratio,crystallinity,crystal carbon size,thermal stability,and resistivity toward oxidation on Ni/KIT-6 in the lower *** comparison,the abundance of acidic sites on Mg1-Al5-hydrotalcite catalyzed the formation of more oxygen-containing species,leading to the formation of carbon nanotubes of rough surface on Ni/KIT-6.