the adsorption of nickel ions onto nanotubes surface and
then increase Ni-loading. The surface area of CNTs
decreases from 99.8 m2/g to 88.7 m2/g after the CNTs are
decorated by Triton, which means that the Triton is
partially incorporated into the channel of nanotubes.
However, the surface area of supported Ni-B amorphous
catalysts increases from 81.7 m2/g (Ni-B/CNTs) to 93.3
m2/g (Ni-B/CNTs-T). In addition, the surface area of
active nickel increases from 19.8 m2/g (Ni-B/CNTs) to
29.9 m2/g (Ni-B/CNTs-T). The enhancement of SBET and
SNi for Ni-B/CNTs-T can be attributed to the high
dispersion Ni-B amorphous particles on CNTs-T, which
is consistent with the TEM results.
Ta b l e 1 Some characteristics of the samples determined by ICP,
BET and CO chemisorption
Sample
Ni-loading/
%
Composition
(molar ratio)
SBET/
(m2·g 1)
SNi/
(m2·g 1)
CNTs 2.21) 0.801)
Ni-B/CNTs 15.752) Ni80.91B19.19 99.83) 81.74)19.82)
Ni-B/CNTs-T 18.052) Ni83.04B16.96 88.73) 93.34)29.92)
1) Values of Ni residue in CNTs ; 2) Values subtracted from Ni
residue in CNTs; 3) Values of CNTs and CNTs-T; 4) Values of
Ni-B/CNTs and Ni-B/CNTs-T
3.2 Catalytic performance
As shown in Fig.3, Ni-B/CNTs-T is more active than
Ni-B/CNTs in the acetylene selective hydrogenation. It is
understandable that higher dispersion of active
components and nickel loading of Ni-B/CNTs-T promote
the acetylene hydrogenation. Additionally, on the whole,
the ethylene selectivity of Ni-B/CNTs-T is higher than
that of Ni-B/CNTs over a wide range of equivalent
acetylene conversion (Fig.4). In acetylene hydrogenation,
the reaction proceeds via three major routes[15 16].
Route one is the hydrogenation of acetylene to ethylene

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