Catalytic polymerization of olefins

Summary

• 1. Kisatibi kieselguhr, which was known earlier only as a carrier for the catalysts in several chemical processes, is a highly active catalyst for isobutylene polymerization.

• 2. Isobutylene polymerization in the presence of kieselguhr (Kisatibi) occurs at 110–240‡ (optimum temperature 150–160‡) and space velocity 50–700 hr⁻¹ (optimum space velocity 500–600 hr⁻¹) with the formation of mainly isobutylene dimers and trimers.

• 3. Kieselguhr is a more active and stable isobutylene polymerization catalyst than is red clay, and has approximately the same activity as does synthetic aluminosilicate cracking catalyst. However, in the presence of kieselguhr the polymerization is carried out more selectively at the expense of decrease in the proportions of secondary cracking and isomerization reaction products.