ANION TREATMENT (F- OR SO42-) OF ALPO4-AL2O3 (25 WT-PERCENT AL2O3) CATALYSTS .3. ANION EFFECT ON SURFACE BASIC PROPERTIES

被引：2

作者：

BAUTISTA, FM ^{[1
]}

CAMPELO, JM ^{[1
]}

GARCIA, A ^{[1
]}

LUNA, D ^{[1
]}

MARINAS, JM ^{[1
]}

ROMERO, A ^{[1
]}

机构：

[1] CORDOBA UNIV,FAC SCI,DEPT ORGAN CHEM,AVDA S ALBERTO MAGNO S-N,E-14004 CORDOBA,SPAIN

来源：

REACTION KINETICS AND CATALYSIS LETTERS | 1993年 / 49卷 / 01期

关键词：

D O I：

10.1007/BF02084046

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：

The effect of both anion type and loading on the amount and strength of basic sites of a series of AlPO4 -Al2O3 (APAl-P, 25 wt.% Al2O3) modified with F- or SO42- ions (1-3 wt.%) was studied. Surface basicity was measured by studying the adsorption of acidic molecules [benzoic acid (BA, pK(a) = 4.2) and phenol (PH, pK(a) = 9.9)], from cyclohexane solutions. The data obtained follow the Langmuir adsorption isotherm and the monolayer coverage at equilibrium (at 298 K), X(m), is assumed as the amount of basic sites corresponding to the specific pK(a) of the acid probe used. The amount of basic sites of anion-treated APAl-P catalysts is lower than that of the unmodified one, and on increasing the anion loading, the basicity of the catalysts gradually decreases. Furthermore, the decrease in surface basicity by anion loading is more accentuated in the case of fluoride ion and, thus, the number of strongest basic sites (measured vs. PH) sharply decreases.

引用

页码：183 / 188

页数：6