Content of sulfates and their stability – key factors determining the catalytic activity of sulfated zirconia catalysts

oleh: ALEKSANDRA ZARUBICA, PAULA PUTANOV, GORAN BOSKOVIC

Format: Article
Diterbitkan: Serbian Chemical Society 2007-07-01

Deskripsi

Two series of sulfated zirconia catalysts were synthesized from various precursors using mono- or multi-step sequence preparations under laboratory con­ditions. Their activities/selectivities in the isomerization reaction of n-hexane were correlated to their textural, structural and morphological properties. The slightly higher activity of a commercially sulfated Zr(OH)4-based catalyst is in agreement with the differences in the content of SO42-- ions and their thermal stability, textural and structural properties, i.e., crystallite size and possible imperfection of the incor­poration of sulfate groups in the multi-step synthesis of the catalyst having a nitrate origin. The employment of H2 as the carrier gas resulted in no catalytic activity, regardless of the catalyst precursor, preparation method and calcination tempera­ture. When the isomerization reaction was performed under He, the relatively short life-times of all catalyst samples were caused by fast deactivation due to coking in the absence of H2.