Environmental Engineering Reference
In-Depth Information
table 24.4
combination of sonocatalytic degradation with other technologies
No.
Organic pollutants
method
Catalyst
Optimum reaction conditions
important findings
references
1.
malachite green (mg)
Sonosorption
Polyacrylic
acid-nanoclay
nanocomposite
(PAA-nanoclay)
22.5 kHz, 120 W, 0.5 g
PAA-nanoclay, 500 mg/l
mg
The adsorption of dye increases with
increase in pH
[116]
The experimental data fit very well with
Freundlich adsorption isotherm,
indicating multilayer adsorption
2.
methyl orange (mO)
Sonophotoelectrocatalytic
degradation
TiO
2
nanotube
40 kHz, 150 W, 253.7 nm uv
lamp with 11 W; TiO
2
nanotube as electrode, mO
5 × 10
−5
m, 40 min; 25°C;
0.5 m Na
2
SO
4
electrolyte
The hybrid processes could efficiently
enhance the degradation efficiency
of meO
[117a]
Pseudo-first-order kinetics
3.
Phenol
Combination of ultrasound
with adsorption
Nanoclay
22.5 kHz, 120 W, phenol
250-5000 mg/l, 0.5 g clay
Adsorption phenomenon is improved
due to sonication
[117b]
Freundlich adsorption isotherm favors
nanoclay
4.
methylene blue (mB)
Sonophotocatalytic
degradation
Fe/TiO
2
28 kHz, Fe/TiO
2
-mWCNT
0.05 g, mB 1.0 × 10
−5
m,
irradiation system with
visible light
The mWCNT deposited with Fe/TiO
2
catalyst showed much higher
sonocatalytic activity than Fe/TiO
2
[114]
Fe/TiO
2
-mWCNT
The mB can be effectively degraded
under visible light, ultrasonic
irradiation, and coupling the two
processes with higher efficiency
Pseudo-first-order kinetic
5.
rhodamine B (rhB)
Sono-Fenton process
Fe@Fe
2
O
3
core-shell
nanowires
25 kHz, 100 W, 0.9 mmol
Fe@Fe
2
O
3
nanowires,
5 mg/l
−1
rhB, air was
bubbled (0.1 m
3
/h
−1
)
This system worked well at neutral pH
[84b]
it was found that Fe@Fe
2
O
3
core-shell
nanowires showed significantly higher
catalytic activity than Fe
0
, Fe
2+
, and
Fe
2+
/Fe
2
O
3
for the degradation of rhB
6.
methyl orange (mO)
Sonophotocatalytic
degradation
Nanosized Ag/TiO
2
Ag/TiO
2
60 mg/l,
meO 37 mg/l, 40 kHz,
200 W, illuminated by
light generated by a
xenon lamp
The activity of nanosized Ag/TiO
2
was
obviously better than that of both
degussa P25 and yili TiO
2
[117c]
Pseudo-first-order kinetics
