Physicochemical Characterization of Highly Dispersed Platinum and Chromium on Zeolite Beta

被引：14

作者：

Izutsu, Yoshiyuki ^{[1
]}

Oku, Yuki ^{[1
]}

Hidaka, Yusuke ^{[1
]}

Kanaya, Naoki ^{[1
]}

Nakajima, Yoshiki ^{[1
]}

Fukuroi, Jun ^{[1
]}

Yoshida, Kaname ^{[2
]}

Sasaki, Yukichi ^{[2
]}

Sekine, Yasushi ^{[1
]}

Matsukata, Masahiko ^{[1
]}

机构：

[1] Waseda Univ, Fac Sci & Engn, Shinjuku Ku, Tokyo 1698555, Japan

[2] Japan Fine Ceram Ctr, Atsuta Ku, Nagoya, Aichi 4568587, Japan

来源：

JOURNAL OF PHYSICAL CHEMISTRY C | 2014年 / 118卷 / 20期

关键词：

N-HEPTANE; ISOMERIZATION; CATALYSTS; OXIDE; HYDROISOMERIZATION; DEHYDROGENATION; SELECTIVITY; PALLADIUM; LOCATION; ALKANES;

D O I：

10.1021/jp500232s

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Structures of platinum and chromium supported on zeolite beta were investigated by XAFS, XPS, UV-vis, NH3-TPD, XRD, CO chemisorption, and molecular dynamics simulation. Both platinum and chromium were uniformly dispersed in the micropore of zeolite beta. Loading of chromium helped platinum to disperse highly and stabilized in the micropore of beta. Major species of platinum on PtCr/beta after calcination at 773 K was Pt2+ forming a Pt-O bond. The Pt-O bond disappeared, and a Pt-Pt bond did not appear by reducing PtCr/beta in hydrogen, accompanying formation of Pt-0. Chromium was loaded as chromate anion in the micropore of zeolite. Results of molecular dynamics simulation showed that Pt2+ associated with CrO42- in the micropore of zeolite beta was more stable than those in the absence of chromium species. We concluded that CrO42- electrostatically stabilizes Pt2+ and inhibits migration and aggregation of platinum.

引用

页码：10746 / 10753

页数：8

共 35 条

[1] Simultaneous isomerization of n-heptane and saturation of benzene over Pt/Beta catalysts -: The influence of zeolite crystal size on product selectivity and sulfur resistance [J].

Arribas, MA ;

Martínez, A .

CATALYSIS TODAY, 2001, 65 (2-4) :117-122

[2] Isomerization of C5-C7 n-alkanes on unidirectional large pore zeolites:: activity, selectivity and adsorption features [J].

Chica, A ;

Corma, A ;

Miguel, PJ .

CATALYSIS TODAY, 2001, 65 (2-4) :101-110

[3] Hydroisomerization of pentane, hexane, and heptane for improving the octane number of gasoline [J].

Chica, A ;

Corma, A .

JOURNAL OF CATALYSIS, 1999, 187 (01) :167-176

[4]

DALLABETTA RA, 1972, P 5 INT C CAT, P1329

[5] Chromia/zirconia catalysts with Cr content exceeding the monolayer. A comparison with chromia/alumina and chromia/silica for isobutane dehydrogenation [J].

De Rossi, S ;

Casaletto, MP ;

Ferraris, G ;

Cimino, A ;

Minelli, G .

APPLIED CATALYSIS A-GENERAL, 1998, 167 (02) :257-270

[6] State of chromium in CrSiBEA zeolite prepared by the two-step postsynthesis method: XRD, FTIR, UV-Vis, EPR, TPR, and XAS studies [J].

Dzwigaj, Stanislaw ;

Shishido, Tetsuya .

JOURNAL OF PHYSICAL CHEMISTRY C, 2008, 112 (15) :5803-5809

[7] Active nonmetallic Au and Pt species on ceria-based water-gas shift catalysts [J].

Fu, Q ;

Saltsburg, H ;

Flytzani-Stephanopoulos, M .

SCIENCE, 2003, 301 (5635) :935-938

[8] LOCATION AND DISPERSION OF PLATINUM IN PTY ZEOLITES [J].

GALLEZOT, P ;

ALARCONDIAZ, A ;

DALMON, JA ;

RENOUPREZ, AJ ;

IMELIK, B .

JOURNAL OF CATALYSIS, 1975, 39 (03) :334-349

[9] STATE AND CATALYTIC PROPERTIES OF PLATINUM AND PALLADIUM IN FAUJASITE-TYPE ZEOLITES [J].

GALLEZOT, P .

CATALYSIS REVIEWS-SCIENCE AND ENGINEERING, 1979, 20 (01) :121-154

[10]

GALLEZOT P, 1976, J MICROSC SPECT ELEC, V1, P1

← 1 2 3 4 →