Development of a satisfactory palladium on activated carbon catalyst for the selective hydrogenolysis of CCl2F2 (CFC-12) into CH2F2 (HFC-32)

被引：30

作者：

Makkee, M ^{[1
]}

van de Sandt, EJAX ^{[1
]}

Wiersma, A ^{[1
]}

Moulijn, JA ^{[1
]}

机构：

[1] Delft Univ Technol, Dept Chem Proc Technol, Sect Ind Catalysis, NL-2628 BL Delft, Netherlands

来源：

JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL | 1998年 / 134卷 / 1-3期

关键词：

CCl2F2; CH2F2; hydrogenolysis; palladium carbide;

D O I：

10.1016/S1381-1169(98)00035-1

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：

A good catalyst for the selective hydrogenolysis of waste CCl2F2 (CFC-12) into the high added value product CH2F2 (HFC-32) has been developed. This catalyst is based on palladium on activated carbon and shows a high selectivity (70-90%) at all conversion levels. It is important to purify the activated carbon support prior to impregnation of the palladium salt. A nitrogen heat pretreatment enhances the stability and activity. During reaction an increase in selectivity to CH2F2 has been found. This increase, without loss in activity, can be explained by further lowering the amount of accessible impurities by the produced HF and HCl. These impurities, like iron and aluminium are responsible for chlorine/fluorine exchange and total hydrogenolysis activities. The activity, selectivity to CH2F2, and the stability of the catalyst is a strong function of the hydrogen to CFC ratio. It was found that during reaction the palladium is converted into palladium carbide. (C) 1998 Elsevier Science B.V. All rights reserved.

引用

页码：191 / 200

页数：10

共 15 条

[1] CONVERSION UNDER HYDROGEN OF DICHLORODIFLUOROMETHANE OVER SUPPORTED PALLADIUM CATALYSTS [J].

COQ, B ;

COGNION, JM ;

FIGUERAS, F ;

TOURNIGANT, D .

JOURNAL OF CATALYSIS, 1993, 141 (01) :21-33

[2]

DODGSEN IL, 1976, PREPARATION CATALYST, V1, P279

[3]

JIN H, 1994, CARBON 94, P352

[4] THE EFFECT OF PRETREATMENT ON PD/C CATALYSTS .1. ADSORPTION AND ABSORPTION PROPERTIES [J].

KRISHNANKUTTY, N ;

VANNICE, MA .

JOURNAL OF CATALYSIS, 1995, 155 (02) :312-326

[5]

LARCHER JR, 1956, T FARADAY SOC, V52, P1500

[6] ATMOSPHERIC FLUORINE COMPOUNDS AS INDICATORS OF AIR MOVEMENTS [J].

LOVELOCK, JE .

NATURE, 1971, 230 (5293) :379-&

[7]

OHNISHI R, 1994, STUD SURF SCI CATAL, V90, P258

[8]

*PROGR ALT FLUOR T, 1992, HFC32 PAFTV

[9] AMBIENT-TEMPERATURE CATALYTIC FLUORINATION OF C-1 CHLOROHYDROCARBONS TO C-3 CHLOROHYDROCARBONS AND RELATED-COMPOUNDS USING OXIDE-SUPPORTED ORGANIC LAYER CATALYSTS [J].

THOMSON, J ;

WEBB, G ;

WINFIELD, J ;

BONNIFACE, D ;

SHORTMAN, C ;

WINTERTON, N .

APPLIED CATALYSIS A-GENERAL, 1993, 97 (01) :67-76

[10] Process for the selective hydrogenolysis of CCl2F2 (CFC-12) into CH2F2 (HFC-32) [J].

Wiersma, A ;

vandeSandt, EJAX ;

Makkee, M ;

Luteijn, CP ;

vanBekkum, H ;

Moulijn, JA .

CATALYSIS TODAY, 1996, 27 (1-2) :257-264

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