Isomerization of Alkanes

Abstract

Publisher Summary This chapter describes the isomerization of butanes, pentanes, hexanes, heptanes, and higher alkanes. The need for isobutane as a charging stock for alkylation processes and the necessity for converting low octane number straight chain hydrocarbons to their higher octane number branched chain isomers, gives an impetus to the study of isomerization of alkanes. The isomerization of liquid paraffins (like pentane and hexane) proceeds in the presence of aluminum halides-hydrogen halides. This isomerization, however, is always accompanied by decomposition. In the case of heptanes and higher molecular weight alkanes, the use of hydrogen is not successful in inhibiting the cracking reaction. The most important catalysts found for this reaction are aluminum chloride and aluminum bromide. Various other catalysts, such as sulfuric acid, and molybdenum oxide also have been investigated for the isomerization of alkanes. The isomerization in the presence of the oxide catalysts proceeds usually at high temperatures and in the presence of hydrogen.