Date post: | 14-Dec-2015 |
Category: |
Documents |
Upload: | elisa-soller |
View: | 214 times |
Download: | 0 times |
Selective Detection of Dialkyl Phthalate by Molecular-sieving Sensor Selective Detection of Dialkyl Phthalate by Molecular-sieving Sensor Naonobu KatadaNaonobu Katada, Ken-ichi Fukuchi, Hideyuki Iwata, and Miki Niwa, Ken-ichi Fukuchi, Hideyuki Iwata, and Miki Niwa
Tottori Univ., Fuji Electric Systems Co. Ltd.Tottori Univ., Fuji Electric Systems Co. Ltd.
Selective deetction
Toluene
SnO2
35 cm35 cm
14 cm14 cm
40 cm40 cm
DAPDAP (dialkyl phthalate) = plasticizer (dialkyl phthalate) = plasticizerSeveral Several g mg m-3-3 of DAP gives damage for device on semiconductor surface of DAP gives damage for device on semiconductor surface
Practical method for analysis of DAPPractical method for analysis of DAP in g mg m-3-3 scale
DOP (Dioctyl phthalate)
DEHP (Bis-2-ethylhexylphthalate)
Selective Detection of Dialkyl Phthalate by Molecular-sieving Sensor Selective Detection of Dialkyl Phthalate by Molecular-sieving Sensor Naonobu KatadaNaonobu Katada, Ken-ichi Fukuchi, Hideyuki Iwata, and Miki Niwa, Ken-ichi Fukuchi, Hideyuki Iwata, and Miki Niwa
Tottori Univ., Fuji Electric Systems Co. Ltd.Tottori Univ., Fuji Electric Systems Co. Ltd.
DBP (Dibutyl phthalate)
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
SnSn4+4+
SnOSnO22 semiconductor gas sensor semiconductor gas sensor
OO2-2- SnSn4+4+ OO2-2- SnSn2+2+ OO2-2- SnSn4+4+ OO2-2-
SnSn4+4+ OO2-2- SnSn4+4+ OO2-2- SnSn4+4+ OO2-2- SnSn4+4+ OO2-2-
SnSn4+4+ OO2-2- SnSn4+4+ OO2-2- SnSn4+4+ OO2-2- SnSn4+4+ OO2-2-
OO2-2- OO2-2- OO2-2- OO2-2-
OO2-2- OO2-2- OO2-2- OO2-2-
OO2-2- OO2-2-
SnSn4+4+ OO2-2- SnSn4+4+ OO2-2-
SnSn4+4+ OO2-2- SnSn4+4+ OO2-2-
SnSn4+4+ OO2-2- SnSn4+4+ OO2-2-
OO2-2- OO2-2-
OO2-2- OO2-2-
OO2-2- OO2-2-
OO2-2- OO2-2- OO2-2- OO2-2- OO2-2- OO2-2-
[ ][ ] OO2-2-
CHCH44
COCO22HH22OO
OO2-2-
Electrical response to flammable compoundElectrical response to flammable compoundReactive for any of organic compoundReactive for any of organic compound
ee-- → →
There are other gases [toluene, isopropaThere are other gases [toluene, isopropanol (IPA) and methylethyl ketone (MEK)] nol (IPA) and methylethyl ketone (MEK)] even in clean rooms.even in clean rooms.
SelectiveSelective detection is needed. detection is needed.
SnOSnO22
OO -
Si(OCH3)4Molecular sieving propertyMolecular sieving property
++
SnOSnO22’s’s
Sensing FunctionSensing Function
OO22
CHO
SiOSiO22 layer layer
COCO22, H, H22OO
CVD of SiOCVD of SiO22 in the presence of molecular template in the presence of molecular template
on SnOon SnO22 surface surface J. Chem. Soc., Chem. Commun.,J. Chem. Soc., Chem. Commun., 1995,1995, 623. 623.
Shape-selective adsorptionShape-selective adsorption Bull. Chem. Soc. Jpn.,Bull. Chem. Soc. Jpn., 78,78, 1425 (2005). 1425 (2005).
Application to molecular-sieving sensorApplication to molecular-sieving sensor Sens. Actuators, B: Chem., 124, 398 (2007)
SnOSnO22
SiOSiO22
catalytic oxidationcatalytic oxidation
Electric responseElectric response
MolecularMolecular--sieving Sensorsieving Sensor
Aim of this studyAim of this study
Application of molecular-sieving sensor to detection of DAP Application of molecular-sieving sensor to detection of DAP in the co-presence of toluene, IPA and MEKin the co-presence of toluene, IPA and MEK
1. Selective detection1. Selective detection
2. Detection in 2. Detection in g mg m-3-3 scale scale
3. Prototype analyzer3. Prototype analyzer
He
SampleSampleElectric furnaceElectric furnace
・ 1-Naphthaldehyde (template) was injected at 343 K・ Si(OCH3)4 vapor was fed at 473 K・ O2 was fed at 673 K
[Sens. Actuators, B: Chem., 124, 398 (2007)]
PreparationPreparation
Air (100 cm3 min-1)
Electric resistanceElectric resistance
0.5 mm0.5 mm33 liquid liquid
673 K673 K
Sensor measurementsSensor measurements
DOP / Toluene / AirDOP / Toluene / Air
Very low concentration of DOP / AirVery low concentration of DOP / Air1. Purification of DOP vapor was carried out;1. Purification of DOP vapor was carried out;
DOP liquid was heated at 383 K for 10 h in He flow.DOP liquid was heated at 383 K for 10 h in He flow.He was further flowed at room temperature for 24 h.He was further flowed at room temperature for 24 h.DOP vapor was trapped to confirm the purity.DOP vapor was trapped to confirm the purity.
2. Thus prepared 4.8 mg m2. Thus prepared 4.8 mg m-3-3 DOP / air was diluted with pure air. DOP / air was diluted with pure air.3. Equipment was heated and completely purged before the measurements.3. Equipment was heated and completely purged before the measurements.
-200 0 200 400 6000
10
20
30
40
t / s
Ra/
R-1
-200 0 200 400 6000
10
20
30
40
t / sR
a/R
-1
DOP
DBP
DEHP
Toluene
IPA
MEK
All compounds detectedAll compounds detected
Results and DiscussionResults and Discussion
0.5 mm3 (as liquid) of
Pd/SnOPd/SnO22 (unmodified) sensor (unmodified) sensor
-200 0 200 400 6000
10
20
30
40
Ra/
R-1
t / s-200 0 200 400 600
0
10
20
30
40
Ra/
R-1
t / s
DOP
DBP
DEHP
Toluene
IPA
MEK
DOP, DEHP, DBP --- selectively detectedDOP, DEHP, DBP --- selectively detected
Toluene, MEK, IPA --- not detected Toluene, MEK, IPA --- not detected
SiOSiO22/Pd/SnO/Pd/SnO22 prepared using 1-NA template (molecular-sieving) sensor prepared using 1-NA template (molecular-sieving) sensor
Why?Why?
Detected by molecular-sieving sensorDetected by molecular-sieving sensorDOPDOP, , DEHPDEHP, , DBPDBP, linear alkane, ethanol, linear alkane, ethanol
UndetectedUndetectedTolueneToluene, , IPAIPA, , MEKMEK, benzene, branched alkane, dimethyl phth, benzene, branched alkane, dimethyl phthalate (DMP)alate (DMP)
Detection of Detection of g mg m-3-3 of DOP of DOP
Response of Pd/SnOResponse of Pd/SnO22 to steady flow of DOP/air to steady flow of DOP/air
-600 0 600 1200 1800
0
0.5
1
t / s
Ra/
R-1
0
1680
160320
480
1600 g m-3
800
640
Detection limit = 500 Detection limit = 500 Target = Target = g mg m-3-3
But the target is not far!But the target is not far!
Concentration of DOP using an Concentration of DOP using an adsorbent column is attempted.adsorbent column is attempted.
vent
sample
adsorbent trap (porous polymer beads)
furnace
sensor
6-way valve
O2
N2
flush by heating
300 cm3 min-1×100 min
0 500 10000
1
2
3
4
5
t / s
Ra/
R-1
8.0 g m-3
4.8 g m-3
Response by Pd/SnO2
Air + DOP Air + Toluene (110 mg m-3)
0 500 10000
1
2
3
4
5
t / s
CDOP = 0 ppb
Ra/
R-1
(toluene only)
5 - 8 5 - 8 g mg m-3-3 DOP was detected. DOP was detected.
0 500 1000-0.1
0
0.1
0.2
0.3
0.4
t / s
Ra/
R-1
CDOP = 0
8.0 g m-3
4.8 mg m-3
Selective response by SiOSelective response by SiO22/Pd/SnO/Pd/SnO22
Air + DOP
4.8 g m-3
8.0 g m-3
0 500 1000-0.1
0
0.1
0.2
0.3
0.4
t / s
CDOP = 0
Ra/R
- 1
Air + Tol. (110 mg m-3)
DOP (5 - 8 DOP (5 - 8 g mg m-3-3), detected), detectedToluene (110,000 Toluene (110,000 g mg m-3-3), not affecting), not affecting
Selective detection of pollutant at a low concentrationSelective detection of pollutant at a low concentration
+ DOP
vent
sample
adsorbent trap (porous polymer beads)
furnace
sensor
6-way valve
O2
N2
flush by heating
300 cm3 min-1×100 min
Complex valvesComplex valvesNN22 and O and O22 supply supply
vent
sample (250 cm3 min-1×40 min)
adsorbent trap(MCM-41, mesoporous silica)
furnace
sensor
Simple systemSimple system
313 313 ~ ~ 423 K ←→ 673 K423 K ←→ 673 K
Adsorbent columnAdsorbent column
Electric furnaceElectric furnace
SensorsSensors
PumpPump
Electric Electric testertester
Temperature Temperature controllerscontrollers
Sample airSample air
A signal (noise) was A signal (noise) was observed by heating observed by heating adsorbent.adsorbent.
5 - 8 5 - 8 g mg m-3-3 is safely detected in any case. is safely detected in any case.
-200 0 200 400 600
0
0.5
1
1.5
Ra/
R-1
t / s
120 g m-3
CDOP = 0
2.4 g m-3
4.8 g m-3
24 g m-3
Collected Collected for 40 minfor 40 min-1-1
Response by Pd/SnO2
Air + DOP
-200 0 200 400 600
0
0.5
1
1.5
Ra/
R-1
t / s
120 g m-3
CDOP = 0
2.4 g m-3
4.8 g m-3
24 g m-3
Collected Collected for 40 minfor 40 min-1-1
Response by Pd/SnO2
Air + DOP
-200 0 200 400 600-1
0
1
2
t / sR
0/R
-1
Pd/SnO2
02.4 g m-3
4.8 g m-3
Air + Toluene (110 mg m-3) + DOP
Unmodified sensorUnmodified sensor
Continuous flow of tolueneContinuous flow of toluene--> Complex change--> Complex change
Signal by DOP hiddenSignal by DOP hidden
Air + Toluene (110 mg mAir + Toluene (110 mg m-3-3) + DOP) + DOP
Unmodified sensorUnmodified sensor
Continuous flow of tolueneContinuous flow of toluene--> Complex change--> Complex change
Signal by DOP hiddenSignal by DOP hidden
-200 0 200 400 600-1
0
1
2
t / s
R0/
R-1
1-NA SiO 2/Pd/SnO2
02.4 g m-3
4.8 g m-3
-200 0 200 400 600-1
0
1
2
t / s
R0/
R-1
Pd/SnO2
02.4 g m-3
4.8 g m-3
Molecular-sieving sensorMolecular-sieving sensor
Response to tolueneResponse to toluene--> Suppressed--> Suppressed
3 - 5 3 - 5 g mg m-3-3 of DOP detected of DOP detected
Collected for 40 minCollected for 40 min-1-1
These are tentative results; final tests are now proceeding.These are tentative results; final tests are now proceeding.
ConclusionsConclusions
1. The molecular-sieving sensor (SiO1. The molecular-sieving sensor (SiO22/Pd/SnO/Pd/SnO22) detected) detected
○ ○ DOP, DEHP, DBP (ethanol, linear alkane)DOP, DEHP, DBP (ethanol, linear alkane)× Toluene, IPA, MEK (DMP, branched alkane)× Toluene, IPA, MEK (DMP, branched alkane)
2. About 5 2. About 5 g mg m-3-3 of DOP could be detected when a suitable of DOP could be detected when a suitable adsorption - desorption system was combined. adsorption - desorption system was combined.
3. 5 3. 5 g mg m-3-3 of DOP was detected within 50 min in the co- of DOP was detected within 50 min in the co-presence of 110 mg mpresence of 110 mg m-3-3 of toluene by a prototype analyzer. of toluene by a prototype analyzer.
Thank you for your kind attention!Thank you for your kind attention!