Butene Oligomerization over Phosphoric Acid: Structural Characterization of Products

In this study, the butene oligomerate produced over solid (SPA) and liquid phosphoric acid (LPA) was analyzed in detail using GC-MS techniques in conjunction with reported retention time data to identify the alkene isomers in the C(6) to C(8) fractions produced by the reaction. This information was used to quantify the oligomerate produced over liquid and solid phosphoric catalysts at different temperatures to identify subtle differences between the product distributions. It is hoped that this information will assist in future studies of the oligomerization reaction since several interesting trends that can be linked to previously proposed mechanisms were observed. Group classification of the identified alkenes according to the number of branches identified tetrasubstituted alkenes as compounds that form in large amounts during the reaction, but these are also removed through cracking faster than the other classes at higher temperatures.