254
WU QINGYOU et al.
CONCLUSIONS
U, mV
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
The singleꢀpass yield of SiHCl3 in existing industrial
scale processes was only 17–19%, with a unit energy
expenditure about 5 kWh/kg, besides, high pressure (at
least 0.2 MPa) is necessary and the ratio of H : SiCl must
be larger than 4. The singleꢀpass yield of SiHCl3 would
rise above 70% with unit energy expenditure only
2
4
3.2 kWh/kg and H : SiCl4 ratio only 2.5 because of the
2
adoption of thermoꢀplasma. It was shown that the optiꢀ
mal temperature for the preparation of SiHCl3 from
hydrogenation of SiCl4 was about 4000 K. As it is easy to
enlarge DC power, this method is possible to be industriꢀ
alized.
0
1
2
3
4
5
τ, min
6
7
8
9
10 11
REFERENCES
Fig. 6. Gas Chromatogram of the Product Gas Mixture.
1
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The main reactions in this experiment were equations
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(
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α
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4
2
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(
(
(
9) and (12) could be combined into one equation
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5
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e
SiCl + 2H
4
SiH Cl + 2HCl,
2
(13)
(14)
2
2
7
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e
SiCl + 2H
4
Si + 4HCl.
2
8
. Qin Pan, Li Xiang, et al., Theoretical Calculation for Therꢀ
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Reactions (13) and (14) were the main byꢀreactions in
this experiment, and as shown in Fig. 6, the fourth peak
must be SiH Cl2, whereas the first was H2, second
2
9. Kravchenko, Yu.S., Osadchuk, et al., Khim. Vys. Energ.,
SiHCl3, third SiCl4 and last HCl.
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INORGANIC MATERIALS Vol. 46
No. 3
2010