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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 C6to C8fractions 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. [ABSTRACT FROM AUTHOR]

High-quality Kieselguhr is normally employed as the support for solid phosphoric acid (SPA), the catalyst used for the oligomerization of C3−C5alkenes in a Fischer−Tropsch refinery. In this paper, we demonstrate that an SPA catalyst of suitable activity can be prepared from a low-quality Kieselguhr provided that the Kieselguhr bulk density is ≤0.3 g/mL. Several catalyst samples were evaluated on microreactor and pilot-plant scale using propene mixtures as feed. An increase in acid-to-Kieselguhr ratio used during catalyst preparation was shown to improve catalyst activity, although this is detrimental to catalyst particle strength under similar calcination conditions. By studying the effect of impurities on catalyst performance, it was confirmed that high impurity levels lower oligomerization activity. It was also established that a high Kieselguhr quartz content (>10% by mass) reduces the catalyst particle crushing strength. [ABSTRACT FROM AUTHOR]