LAYERED ZIRCONIUM-TIN PHOSPHATES .1. CHEMICAL AND PHYSICAL CHARACTERIZATION

被引：9

作者：

BAGNASCO, G

CIAMBELLI, P

FREZZA, A

GALLI, P

LAGINESTRA, A

TURCO, M

机构：

[1] UNIV FEDERICO II NAPOLI, DIPARTIMENTO INGN CHIM, NAPLES, ITALY

[2] UNIV FEDERICO II NAPOLI, DIPARTIMENTO CHIM, NAPLES, ITALY

[3] UNIV ROME LA SAPIENZA, DIPARTMENTO CHIM, I-00185 ROME, ITALY

来源：

APPLIED CATALYSIS | 1991年 / 68卷 / 1-2期

关键词：

LAYERED PHOSPHATES; TIN-ZIRCONIUM; SOLID SOLUTIONS; SURFACE ACIDITY;

D O I：

10.1016/S0166-9834(00)84093-2

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：

Crystalline zirconium-tin phosphates of formula Zr(x)Sn1-x(HPO4)2.H-2O (0 less-than-or-equal-to x less-than-or-equal-to 1) were synthesized and characterized in terms of their physical and chemical properties. From X-ray and thermal analysis it was found that solid solutions are formed for every composition. The tin content in mixed phases has a marked influence on thermal behaviour, speeding up the kinetics of transformation to layered pyrophosphates (L-Py). Mixed phosphates posses surface areas which are markedly higher than pure phosphates. The method of ammonia thermodesorption (TPD) was employed for the acidity measurements. This method has allowed the evaluation of the concentration and strength of surface acid sites present on the external surface of L-Py or mixed hydrogen-L-Py phases obtained after a variety of thermal treatments. The acid strength of L-Py phases increases with increasing tin content.

引用

页码：55 / 68

页数：14