from first principles PP-I-1

PP-III-100Impact of Activation Conditions on the State of the Active Cobalt Surfacein Co-Al Catalysts of Fischer-Tropsch SynthesisSimentsova I.I. 1,2 , Khassin A.A. 1,2 , Minyukova T.P. 1,2 , Rogov V.A. 1,2 , Davydova L.P. 1 ,Yurieva T.M. 11 Boreskov Institute of Catalysis SB RAS, Novosibirsk, Russia2 Novosibirsk State University, Novosibirsk, Russiasii@catalysis.ruCo-based catalysts are well-known as effective catalysts for Fischer-Tropsch synthesis (FTS)from hydrogen-rich syngas. To a great extent activity of the catalysts is determined by thedispersion of Co o particles formed on the surface of the catalysts after reductive activation.Our work was aimed at exploring the possibility of controlling the dispersion of Co o particlesformed in the course of reductive activation of oxide precursors of Co-Alcatalysts. Temperature-programmed reduction (TPR) was used for investigation of thereduction dynamics of oxide precursors formed during the thermal treatment of combinedCoAl hydroxo-nitrate-carbonate compounds having a hydrotalcite-type structure in the inertatmosphere and in the inert atmosphere containing 3-4% vol. NO. It was shown that thereduction occurs in two main stages, that, according to the XRD data [1], correspond to thereduction of Co (III) to Co (II) and then to Co o . The character of reduction depends on theoxidative properties of the gas during thermal pretreatment, particularly at the stage offormation of Co (II) (Figure 1). The specific surface area of Co o was measured by N 2 Otitration method. The catalysts pretreated in NO-containing Ar have higher specific Co osurface area (Table 1). The catalytic tests of obtained catalysts in FTS were performed at 0.1and 2.1 MPa, H 2 :CO:N 2 = 6:3:1, at 210 o C in a fixed bed reactor.10004,0x10 -6 0H 2 absorption, mol/g*s3,0x10 -62,0x10 -61,0x10 -60,021800600400200T, o CFigure 1. TPR curves of the oxide precursorsof sample 1 (Table 1) after their calcination:(1) in 3% vol. NO containing Ar;(2) in pure Ar. The temperature incrementrate 10 K/min.0 20 40 60 80 100 120Time, min259