Magnesium Aluminate Catalyzed Pyrolysis of n-Heptane

Abstract

The effect of magnesium oxide precursor on the activity of magnesium aluminate catalyst for the pyrolysis of n-heptane has been investigated. Magnesium oxide was prepared either from magnesium acetate, magnesium nitrate, magnesium carbonate or hydrated magnesium oxide. In each case, magnesium aluminate (containing 28 wt.% MgO) was prepared. The prepared catalysts were characterized by X-ray diffraction, surface area and pore volume measurement, thermogravimetric analysis and chemisorption of carbon dioxide. Compared to noncatalytic pyrolysis, the conversion of n-heptane increased in the presence of each of the catalysts. Depending on the salt used for the preparation of MgO, the conversion, product yields and coke deposition were different. The cracking activity increased with an increase in the total basicity of the catalyst. Magnesium aluminate prepared using magnesium oxide obtained from magnesium acetate showed the highest conversion as well as the highest yields of ethylene.