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CATTOD-8644; No. of Pages9
ARTICLE IN PRESS
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D.K. Mishra et al. / Catalysis Today xxx (2013) xxx–xxx
nature and shape selective etc, HYZ is selected as support mate-
rial. Here in, we report Ru/HYZ catalyzed selective hydrogenation
of d-glucose to d-sorbitol in liquid phase using water as green sol-
vent with added advantages over conventional catalysts. This paper
describes the kinetics studies of d-glucose hydrogenation using
HYZ supported ruthenium (Ru) catalyst which is prepared by sim-
ple impregnation method. The results obtained from the kinetics
studies of d-glucose hydrogenation experiments are discussed.
and 3.0 Ru/HYZ were also prepared by as described above meth-
ods varying RuCl ·3H O amount. In the entire paper, 0.5 Ru/HYZ,
3
2
1.0 Ru/HYZ, 2.0 Ru/HYZ, 3.0 Ru/HYZ correspond to 0.5, 1.0, 2.0 and
3.0 wt% of ruthenium.
2.3. Catalyst characterization
The metal contents (amount of Ru loading) of the catalysts were
determined by using EDX, Quantax 200 Energy Dispersive X-ray
Spectrometer, Bruker. The amount of metal ions present in the reac-
tion mixture after hydrogenation was analyzed with an inductively
coupled plasma-atomic emission spectrometry (Thermo Scientific
ICAP 6500 duo). Both, morphology and particle size were deter-
mined by the transmission electron microscopy (Maker FEI, Model
Technai G2). For the electron microscopy examination, the catalyst
samples were dissolved in 2-propanol, dispersed carefully in an
ultrasonic bath, and then deposited on carbon-coated copper grids.
2
. Experimental
2.1. Materials
Ruthenium trichloride (RuCl ·3H O) was purchased from Strem
3
2
Chemicals, USA. HY zeolite with Si/Al ratio = 80 used as sup-
port material (written as HYZ) was purchased by the ZEOLYST
International Company, USA. Sodium borohydride (NaBH ), com-
4
BET surface area was determined by N2 adsorption–desorption at
mercial catalyst Ru(5.0%)/C and ethanol were purchased from M/s
Sigma-Aldrich Chemicals, USA. d-Glucose, d-mannose, d-fructose,
d-sorbitol were also purchased from M/s Sigma-Aldrich Chemicals,
USA. Deionized water is used as a solvent. Hydrogen and nitrogen
gases (99.9%) were purchased from Deokyang Co. Ltd and used as
such.
◦
−
196 C liquid N2 temperature with a MICROMETRICS, Tristar II
◦
analyzer. For each measurement, the sample was degassed at 250 C
◦
for 3–4 h, then analyzed at −196 C with N gas at relative pressures
2
(
P/P ) from 0.005 to 1.0 (adsorption) and 1.0–0.1 (desorption). CO
0
chemisorption was carried out by using an instrument model ASAP
020C V1.09G. Before adsorption of the CO, the catalysts (weighed
2
approximately 0.12 g) were pre-treated in He for 35 min, and in O2
2.2. Preparation of catalyst Ru/HYZ
for 15 min, and were then reduced for 30 min in a (5.0%) H /Ar gas
flow of 50 mL/min, and in He gas flow for 15 min at 400 C in a reac-
2
◦
The HYZ supported ruthenium nanoparticles catalyst is pre-
tion chamber. After this pre-treatment, the samples were cooled
down to 50 C under He gas flow and CO pulse measurements were
carried out using (5.0%) CO/He gas flow of 50 mL/min. Finally, the
surface concentration and dispersion of metallic Ru were obtained
from the CO pulse analysis data.
◦
pared by using conventional impregnation–reduction method as
reported in the literatures [25]. To incorporate Ru (1.0% by weight)
on HYZ support, 1.0 g of HYZ and RuCl ·3H O (26 mg) were placed
3
2
together with 10 mL ethanol in a two neck 50 mL round bottom
flask equipped with a mechanical stirrer and a nitrogen inlet. The
resulting mixture was stirred at room temperature under an N2
atmosphere for a period of 24 h. Then, 0.2 M solution of NaBH4 in
ethanol was added drop wise to reaction mixture with constant
stirring; and entire reaction mass was stirred (500 rpm) under N2
atmosphere for a day at room temperature. Ru(III) was reduced
and the Ru (0) nanoclusters were formed which ware stabilized
by HYZ framework. Finally, catalyst was separated by filtration,
washed with ethanol and dried to give dark grey HYZ supported
ruthenium catalyst, 1.0 Ru/HYZ (as shown in Scheme 1). The cata-
lysts having different Ru contents such as 0.5 Ru/HYZ, 2.0 Ru/HYZ
2.4. Catalytic hydrogenation of d-glucose
The d-glucose hydrogenation experiments were carried out
in 300 mL of batch reactor in the temperature range from 100 to
◦
140 C at hydrogen pressure (20–55 bar) by various stirring rate
(400–1200 rpm). The reaction flask was charged with 200 mL of
d-glucose solution and catalyst Ru/HYZ. The reaction mixture was
deoxygenated by purging the nitrogen gas for 30 min at room
temperature. During hydrogenation at different time intervals,
the reaction products were analyzed by using a HPLC (Younglin
Scheme 1. Catalyst preparation and hydrogenation of d-glucose to d-sorbitol.
Please cite this article in press as: D.K. Mishra, et al., Selective hydrogenation of d-glucose to d-sorbitol over HY zeolite supported ruthenium