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containing catalysts are known to be the most active in the glucose
a suitable carrier of the active phase is under discussion. Thus, the
major trend nowadays is to develop new or optimize the exist-
ports are characterized by a comparatively low yield of hexitols
tion of carbon with sulfate groups (Ru/AC-SO3H) allows increasing
the hexitol yield up to 55–60% [24]. Good results were obtained
when using soot particles (Black Pearl, BP, 2000). For example, in
the presence of Pt/BP 2000 the hexitol yield was 57.7% and for
Ru/BP 2000, it was 49.6% [18]. The addition of a small amount of
hydrochloric acid (from 35 to 177 ppm) to the Ru-containing cat-
yield of 30–60% depending on the amount of the catalyst and the
duration of the process [25]. The catalysts based on carbon nano-
authors [26] demonstrated the hexitol yield of 70–75% with the
CNT catalyst containing 1.0% of Ru. Nickel nanoparticles stabilized
on carbon nanofibers (Ni/CNF) provided the hexitol yield of 60–75%
[27,28]. The essential disadvantage of these catalysts is the compli-
cated methods of their preparation.
the vibrating screen. The fractions with the particle size less than
60 m were used for the catalysts preparation.
The catalysts were prepared via a four-steps synthesis accord-
ing to a procedure described elsewhere [31]. This is schematically
described in the scheme (Fig. 1).
2.3. Characterization
Low-temperature nitrogen adsorption was carried out with the
surface analyzer Beckman Coulter SA 3100 to determine specific
surface areas and porosity of the catalysts and the initial HPS sam-
ples. Before the analysis the samples were degassed at 120 ◦C in
vacuum for 1 h using the device for preliminary preparation of the
samples (Coulter Corporation, USA).
Transmission electron microscopy was performed with a Techai
G2 30S-TWIN (FEI, USA) operated at accelerating voltage of 300 kV.
Ru-containing HPS powders were embedded in epoxy resin and
subsequently microtomed at ambient temperature. Images of the
resulting thin sections (ca. 50 nm thick) were collected with the
Gatan digital camera and analyzed with the Adobe Photoshop soft-
ware package and the Scion Image Processing Toolkit.
In this paper a new type of Ru-containing catalysts based on non-
functionalized and functionalized hypercrosslinked polystyrene
(HPS) is proposed for cellulose hydrolytic hydrogenation to
ultra-high porosity and excellent sorption properties and was suc-
cessfully used as a support for nanocomposite catalysts. Active
transformations of substrates occur due to their fast concentrat-
ing in the pores of HPS [29,30]. As HPS can swell in any solvent,
thus the access to catalytic sites is possible in all the reaction media
including water [19].
2.4. Method of cellulose hydrolytic hydrogenation
Cellulose conversion to polyols was carried out in subcritical
water under the following conditions: temperature 245 ◦C, hydro-
gen partial pressure 6 MPa, propeller stirrer speed 600 rpm. The
experiments were performed in a steel reactor (50 cm3, Parr Instru-
ment, USA). Microcrystalline cellulose (0.5 g), a catalyst (0.07 g) and
30 mL of distilled water were loaded into the steel reactor (PARR
Instrument, USA, 50 mL). Then reactor was flushed three times
with hydrogen under pressure. The mixture was heated and stirred
(≈100 rpm) to prevent the formation of local hot spots and the cat-
alyst surface was saturated with hydrogen. After reaching 245 ◦C
the stirrer speed was increased up to 600 rpm. This moment was
chosen as the reaction starting time. At the end of the experiment
the catalyst and non-hydrolyzed cellulose were separated by filtra-
tion. The weight of the non-hydrolyzed cellulose was determined
as the difference between the weight of the residue on the filter
and the catalyst weight. The content of the conversion main prod-
ucts was determined by chromatographic methods in liquid and
gas phases. For the analysis of a gas phase, gas chromatograph
Crystallux-4000 M (MetaKhrom, Russia) was used, while for the
liquid phase, highly effective liquid chromatograph UltiMate 3000
(Dionex, USA) was employed.
2. Experimental
2.1. Materials
HPS Macronet MN-270 (without functional groups), MN-100
(amino groups), and MN-500 (sulfate groups) were purchased from
Purolite Int., U.K. and purified by rinsing with water and drying in
vacuum. Distilled water, gaseous pure hydrogen, microcrystalline
cellulose (degree of crystallinity 75–80%, Chimmedservice, Rus-
sia), and ruthenium (IV) hydroxochloride (pure, OJSC Aurat, Russia)
were used as received.
2.1. Catalyst preparation
Mass spectrometer GCMS-QP2010S (SHIMADZU, Japan) was
used for the chromatography-mass spectrometric analysis of the
liquid phase.
The test for the ruthenium content of the liquid phase was car-
ried out using atomic absorption spectrometer MGA-915 (“Lumex”,
Russia).
HPS granules were washed with water, acetone, and methylic
alcohol and dried at 70 ◦C during the night. Washed and dried HPS
Table 1
Thermogravimetric analysis of the samples of hypercrosslinked
polystyrene MN 270, MN 100, MN 500 was done using thermogravi-
metric analyzer TG 209 IRIS, equipped with differential scanning
equipped with differential scanning calorimeter DSC 204 PHOENIX
(NETZSCH, Germany). The samples analysis was performed under
inert argon atmosphere.
Cellulose conversion was calculated using the formula:
X = (mc0 − mc)/mc0 × 100, where mc is the weight of non-hydrolyzed
cellulose and mc0 is the initial weight of cellulose. A hexitol yield
was calculated using the formula ꢀhex. = mhex./mc0 × 100%, where
mhex. is the weight of sorbitol (or mannitol) formed. The selectivity
was calculated using the formula S = mp/(mc0 − mc) × 100%, where
mp is the weight of the reaction product.
Dependence of X and ꢀhex. on Ru percentage of the catalyst and its amount per
cellulose unit weight.
Variable parameter value:
X, %
ꢀhex., %
Ru percentage of the catalysta:
3.0%
2.0%
1.0%
0.5%
70.0
81.3
91.4
61.0
39.5
36.6
41.0
4.1
Ratio Ru/cellulose (mmol/g)b:
0.042/1
0.028/1
91.4
84.3
41.0
50.4
a
245 ◦C, 6 MPa H2, 30 mL water, Ru/MN-270 (0.042 mmol Ru), 1 g cellulose,
600 rpm, process duration 5 min.
b
The same conditions as in (a) but different Ru/cellulose ratios.
Please cite this article in press as: V.G. Matveeva, et al., Hydrolytic hydrogenation of cellulose in subcritical water with the use of the