Sawdust: A Structural Promoter of Cobalt Catalyst for Fi

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Keywords: biomass, seabuckthorn sawdust, carbon material, cobalt catalyst, magnetometric method in situ, .... method (cobalt (II) sulfate heptahydrate, 21% Со).
ISSN 0036-0244, Russian Journal of Physical Chemistry A, 2016, Vol. 90, No. 9, pp. 1741–1746. © Pleiades Publishing, Ltd., 2016. Original Russian Text © G.V. Pankina, P.A. Chernavskii, V.V. Lunin, 2016, published in Zhurnal Fizicheskoi Khimii, 2016, Vol. 90, No. 9, pp. 1325–1330.

CHEMICAL KINETICS AND CATALYSIS 1

A New Hydrocarbon Material Based on Seabuckthorn (Hippophae rhamnoides) Sawdust: A Structural Promoter of Cobalt Catalyst for Fischer–Tropsch Synthesis G.V. Pankina, P.A. Chernavskii, and V.V. Lunin Faculty of Chemistry, Moscow State University, Moscow, 119991 Russia e-mail: pankina5151@inbox Received November 20, 2015

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Abstract—Aspects of the physicochemical properties of a hydrocarbon material based on seabuckthorn (Hippophae rhamnoides) sawdust are studied. The use of a hydrocarbon material based on sea buckthorn sawdust as a structural promoter of Со/CHip cobalt catalyst in the reaction of CO hydrogenation is shown to require an additional cycling stage in the mode of reduction and oxidation. The resulting mean size of the Co particles is found to be 18–19 nm and is considered acceptable for the synthesis of С5+ liquid hydrocarbons.

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Keywords: biomass, seabuckthorn sawdust, carbon material, cobalt catalyst, magnetometric method in situ, magnetization, coercive force DOI: 10.1134/S0036024416090223

INTRODUCTION Researchers’ interest in the CO hydrogenation process (Fischer–Tropsch synthesis, or FTS) is not waning with time, since the world’s fuel consumption continues to grow and, according to some data, will clearly double by 2050 [1, 2]. Increased attention has therefore been focused on developing inexpensive and highly active metal-containing catalysts, particularly for the CO hydrogenation process (FTS), where carbon materials (CMs) based on biomass or renewable sources of plant origin are mostly used as supports [3, 4]. These materials have highly developed specific surface areas and great dispersity and accessibility. At the same time, the important problem of recycling the agro-industrial and wood wastes used as secondary raw materials is solved. Biomass processing normally consists of pyrolysis and activation in the presence of such reagents as H2SO4, HCl, K2CO3, and KOH [5]. Different ways of preparing catalysts are used, e.g., introducing a metal promoter into a carbon matrix with subsequent thermal treatment in an atmosphere of inert gas or air at high temperatures. Chemical transformations of a deposited metal occur during such treatment, and oxide–oxide interaction with carbon material is excluded [4]. One variety of wood biomass is sea buckthorn sawdust, which could be used as a new sorbent, catalyst support, and fuel. Sea buckthorn is usually used in the food industry; the content of soluble solid compounds varies from 7.4 to 12.6 wt % in different kinds of sea

buckthorn berries with рН ≈ 2.8, and is related to their presence in its wood [6]. Via the chemical activation of sea buckthorn sawdust using solutions of H3PO4 and ZnCl2, the authors of [7] obtained two series of activated carbon, also used as a sorbent, for the purification of waste water contaminated with heavy Pb (II) ions (the recommended content of lead in water is