Liquid phase bromination of phenol II. Over heteropoly acid (HPA)-impregnated zirconium phosphate (ZrP)

被引：31

作者：

Das, D. P. ^{[1
]}

Parida, K. M. ^{[1
]}

机构：

[1] CSIR, Reg Res Lab, BP & EM Dept, Bhubaneswar 751013, Orissa, India

来源：

APPLIED CATALYSIS A-GENERAL | 2006年 / 305卷 / 01期

关键词：

heteropoly acid-impregnated zirconium phosphate; bromination; potassium bromide; hydrogen peroxide; para-selectivity;

D O I：

10.1016/j.apcata.2006.02.046

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：

Heteropoly acid (HPA)-impregnated zirconium phosphate (ZrP) was prepared by an incipient wetness impregnation method by varying the wt.% of HPAs like phosphotungstic acid (PWA), phosphomolybdic acid (PWA), silicotungstic acid (SiWA) and silicomolybdic acid (SiMoA). All the samples were characterized by X-ray diffraction studies, FTIR, determination of acid sites and TG-DTA. The catalytic activities of all the samples were evaluated by carrying out the liquid phase bromination, of phenol using KBr and hydrogen peroxide. The reaction products were analysed by GC through a capillary column. From the product analysis it was found that PWA/ZrP shows the highest conversion. Even so SiWA/ ZrPheated at 110 degrees C shows the highest para-selectivity (in the range of 322-41%), higher than any other HPA/ZrP. The selectivity increases with an increase in the activation temperature up to 400 degrees C and thereafter it remains constant. The reaction proceeds through the formation of Br+ (bromonium ion) which attacks the phenol ring, forming different brominated products. (c) 2006 Elsevier B.V. All rights reserved.

引用

页码：32 / 38

页数：7

共 37 条

[1] HETEROPOLYACIDS AND THEIR SALTS SUPPORTED ON ACIDIC ION-EXCHANGE RESIN AS HIGHLY-ACTIVE SOLID-ACID CATALYSTS [J].

BABA, T ;

ONO, Y .

APPLIED CATALYSIS, 1986, 22 (02) :321-324

[2] Simple and efficient chlorination and bromination of aromatic compounds with aqueous TBHP (or H2O2) and a hydrohalic acid. [J].

Barhate, NB ;

Gajare, AS ;

Wakharkar, RD ;

Bedekar, AV .

TETRAHEDRON LETTERS, 1998, 39 (35) :6349-6350

[3] PHOSPHORIC-ACID ON OXIDE CARRIERS .1. CHARACTERIZATION OF SILICA, ALUMINA, AND TITANIA IMPREGNATED BY PHOSPHORIC-ACID [J].

BUSCA, G ;

RAMIS, G ;

LORENZELLI, V ;

ROSSI, PF ;

LAGINESTRA, A ;

PATRONO, P .

LANGMUIR, 1989, 5 (04) :911-916

[4] The first example of bromination of aromatic compounds with unprecedented atom economy using molecular bromine [J].

Choudary, BM ;

Someshwar, T ;

Reddy, CV ;

Kantam, ML ;

Ratnam, KJ ;

Sivaji, LV .

APPLIED CATALYSIS A-GENERAL, 2003, 251 (02) :397-409

[5] QUATERNARY AMMONIUM-SALTS AS BIFUNCTIONAL CATALYSTS IN THE OXYBROMINATION OF AROMATIC-COMPOUNDS BY AQUEOUS HYDROGEN BROMIDE HYDROGEN-PEROXIDE [J].

DAKKA, J ;

SASSON, Y .

JOURNAL OF THE CHEMICAL SOCIETY-CHEMICAL COMMUNICATIONS, 1987, (19) :1421-1422

[6] Surface properties of titania-supported 12-molybdophosphoric acid hydrodesulphurization catalysts [J].

Damyanova, S ;

Fierro, JLG .

APPLIED CATALYSIS A-GENERAL, 1996, 144 (1-2) :59-77

[7] Liquid phase bromination of phenol over titania pillared zirconium phosphate and titanium phosphate [J].

Das, DP ;

Parida, K .

CATALYSIS COMMUNICATIONS, 2006, 7 (02) :68-72

[8] Solid-state NMR and FT-IR investigation of 12-tungstophosphoric acid on TiO2 [J].

Edwards, JC ;

Thiel, CY ;

Benac, B ;

Knifton, JF .

CATALYSIS LETTERS, 1998, 51 (1-2) :77-83

[9] H3PW12O40 acid dispersed on its Cs salt:: improvement of its catalytic properties by mechanical mixture and grinding [J].

Gayraud, PY ;

Essayem, N ;

Védrine, JC .

CATALYSIS LETTERS, 1998, 56 (01) :35-41

[10]

Gorodetskaya T. A., 1984, USSR Patent, Patent No. 1121255

← 1 2 3 4 →