Geoscience Reference
In-Depth Information
NaOH
HCOOH
!
NaHCOOH
H
2
O
ð
8
:
16
Þ
1
1
5NaHCOO
TiO
2
!
NaTi
ð
OH
Þ
5
1
2Na
2
O
5CO
ð
8
:
17
Þ
1
1
Na
2
O
HCOOH
!
NaHCOOH
NaOH
ð
8
:
18
Þ
1
1
5NaOH
TiO
2
!
NaTi
ð
OH
Þ
5
1
2Na
2
O
ð
8
:
19
Þ
1
2NaTi
ð
OH
Þ
5
1
TiO
2
!
Na
2
Ti
2
O
7
1
5H
2
O
ð
8
:
20
Þ
The solubility of Na
2
Ti
3
O
7
was determined under hydrothermal conditions in
the HCOOH media with a varying temperature and at a constant pressure of 1 kb.
The solubility curve is shown in
Figure 8.21
. It is evident from
Figure 8.21
that the
hydrothermal synthesis of Na
2
Ti
3
O
7
can be carried out within the temperature
range of 350
600
C.
70
60
Pressure 1
kbar
50
40
30
20
100
200
300
400
T
(
°
C)
Figure 8.21 The solubility curve of Na
2
Ti
3
O
7
[84]
.
