KINETIC CHARACTERISATION OF CATALYSTS FOR METHANOL SYNTHESIS

Stanisław Ledakowicz,Lech Nowicki,Jerzy Petera,Andrzej Gołębiowski,Paweł Kowalik,Jarosław Nizioł

doi:10.2478/cpe-2013-0040

Stanisław Ledakowicz, Lech Nowicki + Show 4 more

Open Access

https://doi.org/10.2478/cpe-2013-0040

Copy DOI

Abstract

Abstract The results of activity studies of four catalysts in methanol synthesis have been presented. A standard industrial catalyst TMC-3/1 was compared with two methanol catalysts promoted by the addition of magnesium and one promoted by zirconium. The kinetic analysis of the experimental results shows that the Cu/Zn/Al/Mg/1 catalyst was the least active. Although TMC-3/1 and Cu/Zn/Al/Mg/2 catalysts were characterised by a higher activity, the most active catalyst system was Cu/Zn/Al/Zr. The activity calculated for zirconium doped catalyst under operating conditions was approximately 30% higher that of TMC-3/1catalyst. The experimental data were used to identify the rate equations of two types - one purely empirical power rate equation and the other one - the Vanden Bussche & Froment kinetic model of methanol synthesis. The Cu/ZnO/Al2O3 catalyst modified with zirconium has the highest application potential in methanol synthesis.

Highlights

Methanol is synthesised in two heterogeneous chemical reactions (1) and (2) from a mixture of carbon monoxide and carbon dioxide with hydrogen according to the following reactions: CO + 2H2 = CH3OH (1)CO2 + 3H2 = CH3OH + H2O (2)CO + H2O = CO2 + H2 (3)Methanol was produced for the first time in the industry by the BASF Company in 1923
The aim of this paper was to compare activity of three new catalyst formulations with the standard methanol synthesis catalyst TMC-3/1 commonly used in industry
In order to compare the new synthesised catalysts with the standard TMC-3/1 industrial methanol synthesis catalyst a kinetic analysis of experimental data obtained in the laboratory scale fixed-bed reactor has been performed

Summary

Introduction

The methanol synthesis catalyst used 100 years ago by Pier was based on ZnO–Cr2O3 and required extremely vigorous conditions - pressures ranging up to 30 MPa and temperatures up to 400°C (DR Patent, 1923). In order to reduce the costs of process the ICI group developed in the 1960s the low pressure methanol synthesis using a sulphur-free synthesis gas on Cu/ZnO catalyst (Lange, 2001). The copper/zinc catalyst was discovered and patented more than 10 years earlier by Błasiak (Patent PRL, 1947) and successfully used in the 1950s in Chemical Works in Oświęcim in methanol synthesis (Kotowski, 1963). The advantage of Cu/ZnO/Al2O3 catalyst is the fact that synthesis of methanol takes place at the temperature of 493-553 K and pressure below 10MPa (Skrzypek et al, 1994).

Objectives

Results

Conclusion