Regioselective nitration of o-xylene to 4-nitro-o-xylene using nitric acid over solid acid catalysts

被引:38
作者
Patil, PT [1 ]
Malshe, KM [1 ]
Dagade, SP [1 ]
Dongare, MK [1 ]
机构
[1] Natl Chem Lab, Catalysis Div, Pune 411008, Maharashtra, India
关键词
o-xylene nitration; H-beta; solid acids; 4-nitro-o-xylene;
D O I
10.1016/S1566-7367(03)00097-9
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 regioselective nitration of o-xylene to 4-nitro-o-xylene (4-NOX) has been studied in the liquid and vapor phase over zeolites H-beta, H-ZSM-5 and silica supported molybdenum oxide (MoO3/SiO2) catalysts. Zeolite H-beta showed the maximum conversion of 28% and 63% selectivity for 4-NOX in liquid phase nitration at 70 degreesC with 70% HNO3. The conversion increased to 65% when the reaction was carried out in vapor phase at 150 degreesC using dilute 30% HNO3. The formation of alpha-methylphenyl nitromethane by alkyl nitration in liquid phase was decreased in vapor phase reaction. The formation of oxidation products was also decreased in vapor phase reaction with minor amounts of dinitro and ipso-products. The influence of experimental parameters such as temperature, nitric acid concentration and WHSV on conversion and selectivity has been investigated. The use of dilute nitric acid and the selective formation of 4-NOX using dilute HNO3 makes this process environmental friendly with a potential for commercialization. (C) 2003 Elsevier B.V. All rights reserved.
引用
收藏
页码:429 / 434
页数:6
相关论文
共 6 条
[1]  
BOOTH G, ULLMANNS ENCY IND A, V17, P423
[2]  
CHOUDHARI BM, Patent No. 6376726
[3]   Vapor phase nitration of toluene using dilute nitric acid and molecular modeling studies over beta zeolite [J].
Dagade, SP ;
Waghmode, SB ;
Kadam, VS ;
Dongare, MK .
APPLIED CATALYSIS A-GENERAL, 2002, 226 (1-2) :49-61
[4]   Regioselective nitration of phenol over solid acid catalysts [J].
Dagade, SP ;
Kadam, VS ;
Dongare, MK .
CATALYSIS COMMUNICATIONS, 2002, 3 (02) :67-70
[5]   Selectivity in heterogeneous catalytic processes [J].
Landau, MV ;
Kogan, SB ;
Tavor, D ;
Herskowitz, M ;
Koresh, JE .
CATALYSIS TODAY, 1997, 36 (04) :497-510
[6]  
Tomaz M, 2001, SYNTHETIC COMMUN, V31, P173