Russian Journal of Applied Chemistry, 2010, Vol. 83, No. 5, pp. 901−905.
Pleiades Publishing, Ltd., 2010.
Original Russian Text
S.Yu. Men’shikov, A.V. Vurasko, B.N. Driker, Yu.V. Mikushina, D.V. Eremin, 2010, published in Zhurnal Prikladnoi Khimii, 2010,
Vol. 83, No. 5, pp. 849−853.
AND POLYMERIC MATERIALS
Effect of Impurities in Anthraquinone
on Its Catalytic Activity in Deligniﬁ cation
S. Yu. Men’shikov
, A. V. Vurasko
, B. N. Driker
Yu. V. Mikushina
, and D. V. Eremin
Institute of Organic Synthesis, Ural Branch, Russian Academy of Sciences, Yekaterinburg, Russia
Ural State University of Forestry Engineering, Yekaterinburg, Russia
Received February 19, 2009
Abstract—To evaluate the catalytic activity of anthraquinone in wood deligniﬁ cation, the kinetics of its model
reduction in aqueous alkaline solution was studied. The kinetic and thermodynamic parameters were calculated.
Anthraquinone (AQ) is a widely used catalyst of wood
deligniﬁ cation. However, pure anthracene, the starting
compound for AQ production, is not commercially
produced in Russia, and the cost of imported AQ is high.
Therefore, it is appropriate to examine the applicability
of cheap commercial products containing, along with
anthraquinone, also certain amounts of impurities.
The redox properties of AQ, responsible for the
deligniﬁ cation, are determined by its transformation into
anthrahydroquinone (AHQ) in alkaline solutions [1–3].
Apparently, the catalytic activity of AQ and its capability
for reduction are interrelated and are determined by the
rate and extent of transformation of AQ into AHQ.
In a cooking solution, the AQ consumption varies
from 0.01 to 5% relative to absolutely dry wood (a.d.w.).
In so doing, the gain in the ready product yield ranges
from 1 to 10%, showing poor correlation with the AQ
consumption [4–7]. These differences may be associated
not only with the cooking conditions, but also with the
properties of commercial AQ, depending on the procedure
for its production. Apparently, the quality parameters
given in the technical speciﬁ cations characterize the
capability of AQ for reduction insufﬁ ciently. Therefore,
determination of the physicochemical properties and, in
particular, of the kinetic and thermodynamic parameters
of AQ reduction, determining its catalytic activity, is
a topical problem. Its solution would allow optimization
of the catalytic production of pulp.
As investigation objects we used AQ samples
prepared both by synthesis from phthalic anhydride
and benzene (AQP) and by gas-phase oxidation of
anthracene (AQA), and also AQ waste (AQW) from the
latter process .
As a model reductant we used D-glucose in alkaline
solution. Under its action, AQ is reduced to AHQ in
a nitrogen atmosphere. The AQ reduction was modeled
as applied to the initial period of wood deligniﬁ cation.
In view of the fact that the reduction is a homo-
geneous-heterogeneous reaction, AQW and AQA
samples were preliminarily ground to a particle size of
1 × 10
The speciﬁ c surface area of the samples obtained was
determined by nitrogen desorption. AHQ was detected
H NMR spectroscopy [solvent D
O, proton signals
at 8.34 (H
) and 7.28 ppm (H
An AQ (analytically pure grade) sample (40 mg l
was converted in an alkaline solution of sodium
dithionite (NaOH 24.0 g l
2.6 g l
AHQ. The amount of AHQ formed by the reduction was
determined quantitatively by spectrophotometry (λ =
420 nm, l = 0.5 cm) in a nitrogen atmosphere.
To determine the rate of transformation of AQ
into AHQ, a suspension of the sample containing AQ