Hydrogenation of α-Methylstyrene Linear Dimers
in the Presence of Pd- and Ni-Containing Catalysts
A. N. Khazipova, N. G. Grigor’eva, L. F. Korzhova, and B. I. Kutepov
Institute of Petrochemistry and Catalysis, Russian Academy of Sciences, Ufa, Bashkortostan, Russia
Received December 11, 2008
Abstract—Hydrogenation of α-methylstyrene linear dimers and of 4-methyl-2,4-diphenylpentane on com-
mercial Pd-containing and Ni (GM-3 grade) catalysts was studied under the following conditions: T = 75–190°C,
) = 0.2–0.8 MPa, G
= 2.5–10 wt %, and τ = 1–4 h.
AND POLYMERIC MATERIALS
ISSN 1070-4272, Russian Journal of Applied Chemistry, 2009, Vol. 82, No. 6, pp. 1065–1069. © Pleiades Publishing, Ltd., 2009.
Original Russian Text © A.N. Khazipova, N.G. Grigor’eva, L.F. Korzhova, B.I. Kutepov, 2009, published in Zhurnal Prikladnoi Khimii, 2009, Vol. 82, No. 6,
The development of synthetic oils receives much
attention throughout the world. Possible raw materials
for preparing high-quality synthetic oils are
hydrogenated α-methylstyrene linear dimers (MSDs)
IV and V (see scheme).
Oils containing 2-methyl-2,4-dicyclohexylpentane
(V), compared to petroleum oils, ensure 1.2–2 times
higher friction coefficient (0.09–0.1) and exhibit
higher resistance to heat and oxidation. The Monsanto
company (USA) developed and introduced into
practice lubricating oils with unique properties based
on mono- and dicyclohexylpentanes IV and V .
Procedures for preparing compounds IV and V
have been described in numerous patents [2–5]. For
hydrogenation of α-methylstyrene linear dimers I and
II, it was suggested to use catalysts containing metallic
Ni, Ru, Pd, or Pt. The reaction is performed at elevated
pressure and a temperature from 70 to 200°C for 0.5–10 h.
It was interesting to examine the possibility of
MSD hydrogenation at low pressure. Here we report
on hydrogenation of MSDs and 4-methyl-2,4-diphenyl-
pentane (III) (DPP) in the presence of commercial
Pd- and Ni-containing catalysts at a pressure of 0.2–
Scheme of hydrogenation of α-methylstyrene linear dimers
III IVa IVb V