ISSN 1070-4272, Russian Journal of Applied Chemistry, 2016, Vol. 89, No. 4, pp. 639−643. © Pleiades Publishing, Ltd., 2016.
Original Russian Text © A.V. Terekhov, G.S. Dmitriev, S.N. Khadzhiev, L.N. Zanaveskin, 2016, published in Zhurnal Prikladnoi Khimii, 2016, Vol. 89, No. 4,
Abstract—The extraction of solketal from aqueous glycerol with AI-92 gasoline, toluene, hexane, and 1-hexene
was studied. Aromatic compounds and mixtures containing them exhibit the best extracting properties. A ﬂ owsheet
was suggested for recovering solketal from reaction products by extraction.
Recovery of Solketal from Reaction Products by Extraction
A. V. Terekhov, G. S. Dmitriev, S. N. Khadzhiev, and L. N. Zanaveskin
Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences,
pr. Leninskii 29, Moscow, 119991 Russia
Received March 14, 2016
Solketal (SK, 2,2-dimethyl-4-hydroxymethyl-
1,3-dioxolane) is a promising environmentally clean
oxygenate [1, 2]. Its production can partially solve
the problem of using octane-improving additives of
the previous generation, such as methyl tert-butyl
ether and N-methylaniline. Solketal is produced by
the reaction of glycerol with acetone on acid
The isomer with the ring closed via 1- and 3-OH
groups of glycerol, 2,2-dimethyl-1,3-dioxan-5-ol, is
formed with 2–3% selectivity along with solketal.
Hereinafter, by solketal we will mean the mixture of
isomers formed in the reaction.
Synthesis of solketal is performed at 20–60°С in 2-
to 20-fold molar excess of acetone. If necessary, the re-
action mixture is homogenized with ethanol [3, 4]. The
reaction is reversible; therefore, glycerol is always pres-
ent in the reaction products.
The reaction products containing acetone, solketal,
water, glycerol, and sometimes ethanol are usually sepa-
rated in a cascade of distillation columns. It should be
noted that fractional distillation is power-consuming,
and its contribution to the solketal production cost is
An alternative method for recovering solketal from
reaction products is extraction. This study deals with
the extraction of solketal from reaction products with
gasoline and its components. A process ﬂ owsheet is sug-
gested on the basis of the data obtained.
AI-92 gasoline, toluene, hexane, 1-hexene, and their
mixtures were used as extractants. Experiments were
performed with real solutions obtained after distillation
of acetone from the reaction products.
Experiments were performed at 20°С in a 25-mL
separating funnel. Known amounts of the components
were introduced into the separating funnel. After
vigorous shaking, the mixture was left for 2–6 h until the
phases fully separated and became clear. The solketal