Ing. Quimico

Energy & Fuels 1995,9, 995-998

995

Preparation of Highly Dispersed NiMo Catalysts Supported on Hollow Spherical Carbon Black Particles
Kinya Sakanishi, Ham-umi Hasuo, Isao Mochida," and Osamu Okumat
Institute of Advanced Material Study, Kyushu University,Kasuga, Fukuoka 81 6, Japan Received May 5, 1995@

A special carbon black, Ketjen Black (KB), which has an extremely high surface areaand low specific gravity, was selected as a catalyst support to prepare a highly dispersed NiMo catalyst for the hydrogenation of 1-methylnaphthalene, using a 50 mL magnetically-stirred autoclave under the standard conditions of 380 "C, 40 min, and 9.5 MPa of Ha reaction pressure. The catalyst, prepared from molybdenum dioxyacetylacetonate and nickel acetate in methanol solution by successiveimpregnations of Mo (10 wt %) and Ni (2 wt %) in that order, provided the highest conversion of 84% to methyltetralins. Combinations of soluble metal salts, impregnation solvents, and surface properties of carbon black are suggested to be very important for the preparation of a highly active catalyst. KB-supported NiMo catalysts showed a much higher activity for 1-methylnaphthalene hydrogenation thana commercial NiMo/AlzOs.

Introduction
NiMo and CoMo supported on alumina extrudates are extensively applied in petroleum refineries as hydrotreating catalysts. Alumina is believed t o be one of the best supports because of its large surface area for high dispersion of catalyst species and high mechanical strength for the conventional fxed bed flow reactors. However, such alumina-supportedMo-based catalysts often suffer from coking and plugging problems due t o the acidity or polarity of alumina and the limited activity for heavy polyaromatic hydrocarb~ns.l-~ Hence, modification of the alumina support, or other supports such as T i 0 2 and carbon, have been e ~ a m i n e d . ~ - ~ Furthermore, fine particles of a Mo-based catalyst are applied in a moving bed.*-1° The recovery of thefine particle catalyst from the moving bed is one of the problems t o be solved. The present authors have proposed that carbon-supported catalysts can be recovered after the reactions by gravimetric separation due to their low specific gravity and hydrophobic properties for phase separation.'lJ2
Polymer and Chemical Technology Lab., Kobe Steel, Ltd., Kobe, Hyogo 651-22, Japan. @Abstractpublishedin Advance ACS Abstracts, October 15, 1995. (l)Groot, C. K.;de Beer, V. H. J.; Prins, R.; Stolarski, M.; Niedzwiedz, W. S. Ind. Eng. Chem. Prod. Res. Dev. 1986,25,522530. (2) Hillerova, E.; Vit, Z.; Zdrazil, M.; Shkuripat, S. A.; Bogdanets, E. N.; Startsev, A. N. Appl. Catal. 1991,67, 231-236. (3)Louwers, S. P. A,; Prins, R. J. Catal. 1992,133, 94-111. (4) Mochida. I.: Oishi. T.: Korai. Y.:Fuiitsu. H. Ind. Ene. Chem. , ~, Prod. Res. Dev. 1984,23, 203-205.' (5)Japanese Patent, Showa57-132547 (1982). (6) Paradhan, V.R.; Hemck, D.E.; Tierney, J. W.; Wender, I. Energy Fuels 1991,5,712-720. (7) Duchet, J. C.; van Oers, E. M.; de Beer, V. H. J.; Prins, R. J. Catal. 1983,80,386-402. (8)Kagevama, Y.; Masuvama, T. Proc. Int. Conf. Coal Sci. 1986, 157-160: (9) Kim, S. I.; Woo, S. I. J. Catal.1992,133,124-135. (10) Derbyshire, F. J.; DeBeer, V. H. J.; Abotsi, G . M. K.; Scaroni, A. W.; Solar, J. M.; Skrovanok, D. J . Appl.Cata1. 1986,27, 117-131. (11)Mochida, I.; Sakanishi, K.; Taniguchi, H.; Hasuo, H.; Okuma, 0.Prepr. Pap.-Am. Chem. Soc., Diu. Fuel Chem. 1995,40, 329. (12) Sakanishi, K.;Hasuo, H.; Mochida, I.; OKuma, 0. Prepr. 377. Pap.-Am. Chem. Soc., Diu. Fuel Chem. 1996,40,
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Table1. Some Properties of Ketjen Blacks KB EC KB EC600 J D surface area (m2/g) 800 1270 volatile matter (%) 0.5 0.7 9.0 9.0 PH 30 30 particle size (nm) 145 115 apparent density (g/L) 0.1 01 . ash (%) 1.5 1.5 Ni (ppm) 20 30 V (ppm) 50 100 Fe (ppm) 1 1 Cu (ppm) 1 1 Mn (ppm)

In the present study, Ketjen Black (KB), a unique carbon black, was selected as the support for NiMo. Ketjen Black (KB) is...