Full Papers
doi.org/10.1002/ejic.202100432
Conclusion
We achieved the highly efficient and selective hydrogenation of
D-xylose to D-xylitol in water over an hydrotalcite (HT)-
supported nickel phosphide (Ni P) nanoparticle catalyst. Inter-
2
estingly, while neither nano-Ni P nor HT functioned as a
2
catalyst, the nano-Ni P/HT combination exhibited an excellent
2
catalytic performance in the hydrogenation of D-xylose in terms
of its activity and stability. The high activity of nano-Ni P/HT
2
was also demonstrated in the hydrogenation of D-xylose with
Figure 3. (a) Evaluation of the nano-Ni
xylose over 5 catalytic cycles. Reaction conditions: D-xylose (0.25 mmol),
nano-Ni P/HT (200 mg, 6.2 mol% Ni) (0.91 wt% Ni loading), H O (3 mL), H
2
2
P/HT-catalyzed hydrogenation of D-
only 1 bar of H or at room temperature. Moreover, the success
of the hydrogenation of a concentrated D-xylose solution
2
2
2
(50 wt%), in addition to a high catalyst durability, and the easy
(
(
20 bar), 100°C, reaction time=2 h (red bars) or 30 min (white diamonds).
b) Hot filtration experiment of nano-Ni
2
P/HT: (orange dots) without filtration
handling of nano-Ni P/HT verifies its potential for use in
2
of the catalyst and (blue triangles) with removal of the catalyst by hot
filtration after approximately 20 min. Reaction conditions: D-xylose
practical applications. Previously, cooperative catalysis between
metal phosphides and supports has not been well studied;
however, our results indicated that the combination of a metal
phosphide and a support is a promising method for designing
nanostructured catalysts with high activities and stabilities for
diverse reaction applications.
(
(
2 2
0.25 mmol), nano-Ni P/HT (200 mg, 6.2 mol% Ni) (0.91 wt% Ni loading), H O
3 mL), H
2
(20 bar), 100°C.
8
52.4 and 869.4 eV, which are similar to those observed for the
fresh nano-Ni P/HT (Figure 2 and Figure S2). TEM and EDX
2
analyses of the spent nano-Ni P/HT show that both the average Experimental Section
2
particle diameter and the Ni/P molar ratio of the spherical
nano-Ni P species are close to those of the fresh catalyst
Preparation of nano-Ni P/Support
2
2
(
Figure S3 and Figure S4). Overall, these results strongly support
Under an argon atmosphere, a Schlenk flask equipped with a
stirring bar was charged with Ni(acac) (1.0 mmol), CH (CH ) NH
2
the high stability of the nano-Ni P/HT catalyst.
2
2
3
2 15
Table 2 summarizes our comparison carried out between
(10 mmol), and P(OPh) (10 mmol). The reaction mixture was heated
3
À 1
nano-Ni P/HT and some previously reported non-noble metal
catalysts in terms of their catalytic performances for the
hydrogenation of D-xylose. nano-Ni P/HT clearly outperformed
to 315°C at a rate of 30°Cmin and maintained at this target
2
temperature for 2 h. After cooling the reaction mixture to room
temperature, acetone (10 mL) was added to precipitate the black
2
solid which was then washed with a CHCl –acetone (1:1, v/v)
3
the reported catalysts in terms of a quantitative synthesis of D-
xylitol (Table 2, entry 1 vs. entries 6–12), mild operating con-
ditions (Table 2, entries 2 and 3), applicability to a concentrated
D-xylose solution (Table 2 entry 4 vs. entries 6 and 7), and a
more than 10-fold higher TON value (Table 2, entry 5 vs.
entry 6). Hence, nano-Ni P/HT has great potential for use as an
alternative to conventional catalysts for the production of D-
xylitol.
mixture (10 mL). The obtained solid was dried in vacuo to yield
nano-Ni P (90 mg) as a black powder. Loading nano-Ni P on HT was
2
2
as follow: HT (1.0 g) was added to a suspension of nano-Ni2P
(30 mg) in n-hexane (100 mL). After stirring the mixture overnight
at room temperature, the precipitate was filtered and the obtained
solid was dried in vacuo to afford nano-Ni P/HT (1.0 g) as a gray
2
2
powder. For comparison of the catalytic activity of nano-Ni P/HT
2
with other catalysts, nano-Ni P supported on other metal oxides
2
(
i.e., Al O , MgO, ZrO , TiO , or SiO ) in addition to Co phosphide
2 3 2 2 2
nanoparticles supported on HT (nano-Co P/HT), were also prepared
2
in a similar manner to nano-Ni P/HT (see the Supporting Informa-
2
tion). Ni/HT and its H -reduced form (Ni/HT-Red) were also
2
Table 2. Comparison with previous reports for the D-xylose hydrogenation reaction.
Entry
Catalyst
Conditions
D-xylitol yield [%]
TON
Ref.
1
2
3
4
5
nano-Ni
nano-Ni
nano-Ni
nano-Ni
nano-Ni
2
2
2
2
2
P/HT
P/HT
P/HT
P/HT
P/HT
2.4 wt% D-xylose, 6.2 mol% Ni, 100°C, 20 bar H
2
, 2 h
, 12 h
>99
87
>99
88
16
14
8
88
960
This work
This work
This work
This work
This work
2.4 wt% D-xylose, 6.2 mol% Ni, 100°C, 1bar H
2
2.4 wt% D-xylose, 12.4 mol% Ni, 25°C, 50 bar H
, 72 h
2
50wt% D-xylose, 1.0 mol% Ni, 100°C, 50 bar H
, 20 h
2
20 wt% D-xylose, 0.1 mol% Ni, 80°C, 50 bar H
, 36 h
96
2
6
7
8
9
0
1
2
Co/SiO
Raney Ni
2
33 wt% D-xylose, 1.3 mol% Co, 140°C, 50 bar H
2
, 4 h
2
, 1–2 h
90
73
10
50
30
62
73
71
5
–
4
2
6
7
[10]
[12]
[7]
[5]
[6]
[8]
[8]
52 wt% D-xylose, 7.9 mol% Ni, 130°C, 70 bar H
4.0 wt% D-xylose, 8.1 mol% Ni, 100°C, 25 bar H
1.2 wt% D-xylose, 8.0 mol% Ni, 100°C, 25 bar H
1.6 wt% D-xylose, 8.0 mol% Ni, 100°C, 25 bar H
4.8 wt% D-xylose, 9.3 mol% Ni, 100°C, 40 bar H
4.8 wt% D-xylose, 9.3 mol% Ni, 100°C, 40 bar H
Nd0.5Ce0.5Al0.162Ni0.838
La0.3Ce0.7Al0.18Ni0.82
LaAl0.18Ni0.82
Raney Ni
O
3
3
2
, 1–2 h
, 4 h
, 4 h
, 2 h
O
2
2
2
2
1
1
1
O
3
Ni/SiO
2
, 2 h
Eur. J. Inorg. Chem. 2021, 1–6
4
© 2021 Wiley-VCH GmbH
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