from first principles PP-I-1

PP-III-29Supercritical Fluid – CO 2 Regeneration of the Nickel-on-Kieselguhr CatalystGallyamov R.F. 2 , Sagdeev A.A. 1 , Gumerov F.M. 2 , Sagdeev K.A. 21 Nizhnekamsk Institute of Chemical-Technology KNRTU, Nizhnekamsk, Russia2 Kazan National Research Technological University, Kazan, Russiarustick_g@rambler.ruThe nickel-on-kieselguhr supported catalyst is employed for purifying isoprene fromacetylene compounds, more specifically butyl acetylene and isopropyl acetylene. During theprocess catalytic reactivity reduction is occurred, because the deposition of coke at thecatalyst surface.The composition of decontaminant was determined by IR-spectroscopy. Essentially there areproducts of reaction: isoprene’s oligomers, isoamylenes cis- and trans-, isopropyl groupcompounds and loose oxidation products.In the first series of experiments, the regeneration of the catalyst was implemented using pureSC CO 2 at temperatures of 343 K and 423 K and pressures of 10, 20, and 30 MPa.In subsequent experiments regeneration of catalyst was accomplished using modified(methanol 3%-mass fraction of carbon dioxide) supercritical carbon dioxide at thetemperature Т = 343 К and pressure Р = 15, 20 MPa.The conducted analysis of regenerated catalyst samples revealed recovery of catalytic activityup to 92 %. That confirmed a possibility of SCF CO 2 extraction implementation for catalystregeneration.Fig. 1. Change in the mass of the catalyst in the course of its regeneration versus the amount ofextractant used: (1–6) SC CO 2 and (7, 8) SC CO 2 +3 wt % methanol; (1–3, 7, 8) 343 K and(4–6) 423 K; (1, 4) 10 MPa, (2, 5, 8) 20 MPa, (3, 6) 30 MPa, and (7) 15 MPa.181