Nature and Catalytic Properties of In-Situ-Generated Bronsted Acid Sites on NaY

doi:10.1021/acscatal.8b03936

	Nature and Catalytic Properties of In-Situ-Generated Bronsted Acid Sites on NaY
	Murhy, Brian M.1; Wu, Jingcheng 1,2,3,4,5; Cho, Hong Je 1; Soreo, Juliana 1; Wang, Chenguang 2,3,4,5; Ma, Longlong 2,3,4,5; Xu, Bingjun 1
刊名	ACS CATALYSIS
	2019-03-01
卷号	9 期号:3 页码:1931-1942
关键词	zeolites Bronsted acid sites NaY catalysts acetic acid methyl acetate
ISSN号	2155-5435
DOI	10.1021/acscatal.8b03936
通讯作者	Xu, Bingjun(bxu@udel.edu)
英文摘要	Aluminosilicate zeolites are widely used as acid catalysts, and different types of acid sites on these materials have been identified and characterized thoroughly. However, distinct acid sites on zeolites generated during reaction, such as the Bronsted acid sites on NaY upon exposure to organic acids and esters shown in our recent works (referred to as 0 extrinsic sites), remain largely unexplored. In this work, we determine the density of extrinsic Bronsted acid sites generated on NaY by acetic acid and methyl acetate by quantitative Fourier transform infrared (FTIR) spectroscopy. Kinetic investigations using isopropanol dehydration as a model reaction show that the catalytic characteristics of the extrinsic Bronsted acid sites on NaY are not only different from intrinsic Bronsted acid sites on proton-exchanged faujasites, but also are dependent on the precursor molecule (e.g., acetic acid and methyl acetate). The rate of isopropanol dehydration on NaY is found to scale linearly with the square root of the partial pressure of cofed acetic acid, rather than the quantity of spectroscopically measured Bronsted acid sites. We propose that the self-dissociation of acetic acid in the highly ionic zeolite pore network generates protons that are active for the dehydration reaction, and only fraction of these protons, i.e., those that are associated with the zeolite framework, can be identified spectroscopically. When cofeeding methyl acetate, the rate of isopropanol dehydration on NaY increases linearly with the quantity of spectroscopically measured Bronsted acid sites, which is attributed to the fact that the self-dissociation of methyl acetate does not generate active protons within the zeolite pore.
资助项目	National Science Foundation, CBET[CBET-1437129] ; China Scholarship Council
WOS关键词	METHYL LACTATE ; VIBRATIONAL-SPECTRA ; ACETIC-ACID ; ZEOLITES ; DEHYDRATION ; CONFINEMENT ; ADSORPTION ; STRENGTH ; NMR
WOS研究方向	Chemistry
语种	英语
出版者	AMER CHEMICAL SOC
WOS记录号	WOS:000460600600031
资助机构	National Science Foundation, CBET ; China Scholarship Council
内容类型	期刊论文
源URL	[http://ir.giec.ac.cn/handle/344007/24652]
专题	中国科学院广州能源研究所
通讯作者	Xu, Bingjun
作者单位	1.Univ Delaware, Dept Chem & Biomol Engn, Ctr Catalyt Sci & Technol, 150 Acad St, Newark, DE 19716 USA 2.Chinese Acad Sci, Guangzhou Inst Energy Convers, Guangzhou 510640, Guangdong, Peoples R China 3.Chinese Acad Sci, Key Lab Renewable Energy, Guangzhou 510640, Guangdong, Peoples R China 4.Chinese Acad Sci, Guangdong Prov Key Lab New & Renewable Energy Res, Guangzhou 510640, Guangdong, Peoples R China 5.Univ Chinese Acad Sci, Beijing 101408, Peoples R China
推荐引用方式 GB/T 7714	Murhy, Brian M.,Wu, Jingcheng,Cho, Hong Je,et al. Nature and Catalytic Properties of In-Situ-Generated Bronsted Acid Sites on NaY[J]. ACS CATALYSIS,2019,9(3):1931-1942.
APA	Murhy, Brian M..,Wu, Jingcheng.,Cho, Hong Je.,Soreo, Juliana.,Wang, Chenguang.,...&Xu, Bingjun.(2019).Nature and Catalytic Properties of In-Situ-Generated Bronsted Acid Sites on NaY.ACS CATALYSIS,9(3),1931-1942.
MLA	Murhy, Brian M.,et al."Nature and Catalytic Properties of In-Situ-Generated Bronsted Acid Sites on NaY".ACS CATALYSIS 9.3(2019):1931-1942.