Role of temperature and hydrochloric acid on the formation of chlorinated hydrocarbons and polycyclic aromatic hydrocarbons during combustion of paraffin powder, polymers, and newspaper

Article abstract of DOI:10.1007/s00244-006-0185-1

Formation of chlorinated hydrocarbons and polycyclic aromatic hydrocarbons (PAHs) were determined using a laboratory-scale incinerator when combusting materials at different temperatures, different concentrations of hydrochloric acid (HCl), and when combusting various types of polymers/newspaper. Polychlorobenzenes (PCBz), polychlorophenols (PCPhs), polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) and their toxic equivalency (TEQ) and PAHs were highlighted and reported. Our results imply maximum formation of chlorinated hydrocarbons at 400°C in the following order; PCBz≥PCPhs?PCDFs>PCDDs>TEQ on a parts-per-billion level. Similarly, a maximum concentration of chlorinated hydrocarbons was noticed with an HCl concentration at 1000 ppm with the presence of paraffin powder in the following order; PAHs>PCBz≥PCPhs?PCDFs>PCDDs>TEQ an a parts-per-billion level. PAHs were not measured at different temperatures. Elevated PAHs were noticed with different HCl concentrations and paraffin powder combustion (range: 27-32 μg/g). While, different polymers and newspaper combusted, nylon and acrylonitrile butadiene styrene (ABS) produced the maximum hydrogen cyanide (HCN) concentration, concentrations of PCDD/FS, dioxin-like polychlorinated biphenyls (DL-PCBs), and TEQ were in a decreasing order: polyvinylchloride (PVC)

Full text of DOI:10.1007/s00244-006-0185-1

Arch. Environ. Contam. Toxicol. 53, 8–21 (2007)
DOI: 10.1007/s00244-006-0185-1
Role of Temperature and Hydrochloric Acid on the Formation of Chlorinated
Hydrocarbons and Polycyclic Aromatic Hydrocarbons During Combustion of
Paraffin Powder, Polymers, and Newspaper
Takumi Takasuga,1 Norihito Umetsu,1 Tetsuya Makino,2 Katsuya Tsubota,2 Kenneth S. Sajwan,3
Kurunthachalam Senthil Kumar1,3
1
Shimadzu Techno-Research Inc., 1 Nishinokyo-Shimoaicho, Nakagyo-ku, Kyoto 604-8436, Japan
Japan PVC Environmental Affairs Council, Uchisaiwaicho 2-1-1, Chiyoda-ku, Tokyo 100-0011, Japan
Department of Natural Sciences and Mathematics, Savannah State University, 13219 College Street, Savannah, GA 31404, USA
2
3
Received: 31 August 2006 /Accepted: 11 December 2006
Abstract. Formation of chlorinated hydrocarbons and polycy-
clic aromatic hydrocarbons (PAHs) were determined using a
laboratory-scale incinerator when combusting materials at dif-
ferent temperatures, different concentrations of hydrochloric
acid (HCl), and when combusting various types of polymers/
newspaper. Polychlorobenzenes (PCBz), polychlorophenols
(PCPhs), polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs)
and their toxic equivalency (TEQ) and PAHs were highlighted
and reported. Our results imply maximum formation of chlori-
nated hydrocarbons at 400ꢀC in the following order;
PCBz‡PCPhs>>PCDFs>PCDDs>TEQ on a parts-per-billion
level. Similarly, a maximum concentration of chlorinated
hydrocarbons was noticed with an HCl concentration at 1000
ppm with the presence of paraffin powder in the following or-
der; PAHs>PCBz‡PCPhs>>PCDFs>PCDDs>TEQ an a parts-
per-billion level. PAHs were not measured at different tem-
peratures. Elevated PAHs were noticed with different HCl
concentrations and paraffin powder combustion (range: 27–32
lg/g). While, different polymers and newspaper combusted,
nylon and acrylonitrile butadiene styrene (ABS) produced
the maximum hydrogen cyanide (HCN) concentration,
concentrations of PCDD/FS, dioxin-like polychlorinated
biphenyls (DL-PCBs), and TEQ were in a decreasing order:
polyvinylchloride (PVC)<newspaper<polyethyleneterephtha-
late (PET)< polyethylene (PE)< polypropylene (PP)< ABS =
blank. Precursors of PCBs were in a decreasing order:
PP<nylon<PE<newspaper<ABS<PVC<blank<PET. Precur-
sors of PCDD/Fs were in a decreasing order: newspaper
<PP=nylon<PE<ABS<PVC= blank<PET. BTX formation was
in a decreasing order; PE<nylon<newspaper<ABS<PP. PAHs
formation were elevated with parts-per-million levels in the
decreasing order of PP<nylon<PE<newspaper<blank<ABS<
PET<PVC.
Formation of polychlorinated dibenzo-p-dioxins (PCDDs) and
polychlorinated dibenzofurans (PCDFs) as a result of muni-
cipal solid waste incinerators (MSWI) was discovered in 1977
(Olie et al. 1977). Particularly, formation of PCDD/Fs in
MSWIÕs and industrial solid waste incinerators (ISWIs) in-
volved complex and heterogeneous chemistry (Huang and
Buekens, 1995; Fiedler, 1998; Tuppurainen et al. 1998; lino
et al. 1999a, b; 2000; 2001). European Union (EU) member
countries have set limit values for PCDD/DF emissions for
hazardous waste incinerator plants of 0.1ng I-TEQ/Nm3.
According to the latest inventory of PCDD/DF, emissions from
MSWIÕs in Japan were 812 g-TEQ/y until 2001 (Suzuki et al.
2004). Consequently, insight into the formation of toxic con-
taminants is of the utmost important. The presence of PCDD/
Fs in incinerator fly ash has led to laboratory-scale modeling in
the formation process. Earlier reviews summarized the most
important trends in formation chemistry (Addink and Olie
1995; Altwicker 1996; Fiedler 1998; Stieglitz 1998, Huang
and Buekens 1999; Weber and Hagenmaier 1999). In our
earlier study, we demonstrated the formation of dioxin during
burning of newspaper, kerosine, paraffin powder, and plastics
with dioxin-free fly ash (Takasuga et al. 2000). In general
practice, hydrochloric acid (HC1) was formed from sodium
chloride (NaCl) when heating NaCl, which contains waste
along with clay (Yasuhara et al. 2001). Other studies demon-
strated that copper chloride (CuCl2) is a major source of
PCDD/Fs (Wang et al. 2002; Ryu et al. 2003; Shibata et al.
2003). In addition, in order to understand the formation of
dioxins from HC1 and CuCl2, studies are needed not only on
PCDD/Fs but also an other chlorinated hydrocarbons such as
polychlorobenzenes (PCBz) and polychlorophenols (PCPhs)
(Hagenmaier et al. 1987). Besides, burning experiments sug-
gested that polycyclic aromatic hydrocarbons (PAHs) are the
Present address: Department of Natural Sciences and Mathematics,
Savannah State University, P.O. Box 20600, Savannah, GA 31404,
USA.
Correspondence to: Kurunthachalam Senthil Kumar; email: kskumar
@savstate.edu

Formation of Chlorinated-Benzenes,-Phenols,-Dioxins,-Furans, PAHs, PCBs During Combustion of Various Catalysts
9
Fig. 1. The experimental apparatus employed for
the first and second objective of this study
PVC (local hardware shop). Prior to the experiment, PE, PET, nylon,
newspaper, PP, ABS, and PVC were either cut into tiny pieces or
powdered with a heavy grinder.
predominant chemicals evolved during these complex reac-
tions (Takasuga et al. 2003).
Recent studies reported formation of PCDD/Fs during
combustion of newspapers with the presence of NaCl and
polyvinyl chloride (PVC) (Yasuhara et al. 2001). Yasuhara
and the co-workers also reported the formation on PCDD/Fs
coplanar PCBs during combustion of plastics, newspaper, and
pulp (Yasuhara et al. 2002, 2005) in an incinerator with the
presence of inorganic chlorides and various woods (Yasuhara
et al. 2003). More experiments and theoretical studies to elu-
cidate the details of orhanohalogen compound formation in
combustion are urgently needed. Considering those facts, we
developed a laboratory-scale incinerator in order to understand
the formation of toxic contaminants with three different
objectives: (1) temperature - dependent formation of PCDDs,
PCDFs, PCDD/DF-TEQ, PCBz, and PCPhs during the burning
of paraffin powder, dioxin-free fly ash, and at various degrees
of temperature; (2) formation of PAHs PCDDs, PCDFs,
PCDD/DF-TEQ, PCBz, and PCPhs at different HCl concen-
trations, the presence of paraffin powder and newspaper
impregnated with dioxin-free fly ash; and (3) formation of
PAHs, PCDDs, PCDFs, polychlorinated biphenyls (PCBs),
TEQ, benzene, toluene, xylene (BTX), HCN, precursors of
PCBs and PCDD/Fs, and carbon monoxide (CO) from poly-
ethylene (PE), polyethyleneterephthalate (PET), nylon, news-
paper, polypropylene (PP), acrylonitrile butadiene styrene
(ABS), and polyvinylchloride (PVC) plastic particles with a
modified incinerator that differs from first two objectives
instrument. Based on the formation of PAHs, PCBz, PCPhs,
PCDD/Fs, DL-PCBs, TEQ using I-TEF values were calculated
and discussed.
Experiment
For the first two objectives, the incinerator apparatus shown in Fig. 1.
was employed as described elsewhere (Ohta et al. 2002, 2004). The
apparatus consisted of a O2=20.9%/N2 balance meter that connected
with the flow meter and quartz tube. The diameter of the quartz tube is
25 mm with a 1000-mm length that mainly travels inside the double
furnace (600 mm) with a furnace temperature of 900ꢀC and 300ꢀC,
respectively. The samples for the formation test were placed in the
sample boat located in the quartz tube in furnace 1. Sampling unit for
the PCDD/Fs, PCBz, PCPhs, and PAHs was classified as an ice-bath
with three impinger and Amberliteꢁ XAD. The impinger 1 contains
100 mL water. The impinger 2 and 3, respectively, contain 100 mL
toluene and 100 mL diethylene glycol, respectively. The impinger was
connected with Amberliteꢁ XAD in which sampling was done along
with the impinger. The Amberliteꢁ XAD unit was finally connected
with a flow meter with a pump and a CO, O2 CO2 monitoring meter.
After the completion of each experiment the back end of the quartz
tube, the impinger,was rinsed with H2O, acetone, and toluene for
consecutive analysis. For the first objective, paraffin powder (10 lg)
was sprayed 100 times (total 1g) in a duration of 2 h. The HCl con-
centration was maintained as 100 ppm, which is a general incinerator
concentration at solid burning conditions. The furnace temperature
was adjusted to 100ꢀC, 200ꢀC, 300ꢀC, 400ꢀC, and 500ꢀC in dioxin-
free fly ash zone. Three blank tests were conducted prior to the real
experiment with the aforesaid temperatures.
For the second objective, HCl concentrations were adjusted to 10,
50, 100, 500, and 1000 ppm in order to understand its impact on the
formation of target compounds. The experiment was mainly con-
ducted with paraffin powder with fly ash. Three blank tests were
conducted prior to the sample experiment. The experiment was also
conducted with dioxin-free paraffin powder and newspaper. Extrac-
tion and cleanup procedures and analysis were the same as JIS K 0311
methods with minor modifications (Takasuga et al. 2000).
For the third objective, an experimental apparatus was developed
with a O2=20.9%/N2 balance meter that further connected with a flow
meter and a quartz tube (Fig. 2). The diameter of the quartz tube is
25 mm with a 1000-mm length that mainly travels inside the double
furnace (600 mm) with both furnace temperatures set to 900ꢀC. The
samples for the formation test were placed in the sample boat located
in the quartz tube in furnace 1. For PCDD/Fs and PAHs analysis,
sampling was done in three impingers and a two Amberliteꢁ XADÕs.
The impinger 1 contains 100 mL toluene with 200 mL H2O. The
impinger 2 and 3, respectively, contain 150 mL toluene and 150 mL
diethylene glycol. The last impinger was connected with Amberliteꢁ
XAD-1 and 2. For HCN, the ice-batch contains impingers filled with
30 mL of 0.1 mol/L NaOH solution. For BTX analysis, a 10-L
Flek sampler bag was fixed to the incinerator. The impinger and
Materials and Methods
Samples
Fly ash was obtained from the electrostatic precipitator of MSWI. The
fly ash was subjected into thermial heat at 500ꢀC for 2 h in the
presence of a nitrogen stream that removed 99.99 % of PCDD/Fs,
sieved to 5um thickness, which served as dioxin-free fly ash. This
dioxin-free fly ash was used as a catalyst. However, it contained
unburnt carbon in the range of 2.0–2.2%. HC1 applied to the com-
bustion was purchased from Takachiho Chemical Ind., Ltd., Tokyo,
Japan. The polymer sample materials employed were the commer-
cially available films PE and PET (Futamura Chemical Ind., Co., Ltd.,
Nagoya, Japan), nylon (Mitsubishi Chemical Kohjin PAX Corp.,
Tokyo, Japan), PP (Daicel Chemical Ind., Ltd., Osaka, Japan), par-
affin powder (Kyoto Chemical Company, Kyoto, Japan), ABS and

10
T. Takasuga et al.
Fig. 2. The experimental apparatus employed for
the third objective of this study
Amberliteꢁ XADs were finally connected with a pump and a CO, O2,
CO2 monitoring meter (Fig. 3). After the completion of each experi-
ment, the back end of the quartz tube, the impinger, was rinsed with
H2O, acetone, and toluene. The sampling speed and gas flow were set
to 2.0 L/min trapping time. For dioxin and PAHs analysis, a 1-g
sample was used 100 cycles with 20-lg sample each time (until
completion of CO, CO2, and O2, monitor cycles), whereas 200- and
100-lg samples were used for HCN and BTX analysis with 20 and 10
cycles, respectively, with non-chlorinated polymers. The interval be-
tween test repetitions was approximately 1.5 min. Residence time in
the second stage furnace was calculated as approximately 3 s.
Chemical Analysis
After combustion of each experiment, water, toluene, and diethylene
glycol were mixed and liquid–liquid extraction was employed with
toluene. Quartz wool and Amberliteꢁ XAD-2 were soxhlet extracted
for 16 h with 300 mL toluene. Liquid–liquid extracts were combined
with soxhlet extract and the volume was reduced to 20 mL by a rotary
evaporator. The cleanup of the PCBz and PCPhs was performed from
20- to 50-lL of the crude extract after adding
PCPhs as an internal standard. In order to remove -OH group from
PCPhs, the trimethylsilylation (TMS) procedure was employed. For
13
C -
-PCBz and 13C12
12
13
PCDD/Fs, in 2 mL of crude extract
C -labeled 2,3,7,8-chlorine
12
substituted tetra-, penta, hexa-, hepta, and octa-PCDD/Fs were spiked
and passed through a multilayer silicagel column (multilayer consists
of silica, 10% AgNO3/silica, silica, 22% H2SO4/silica, 44% H2SO4/
silica, silica, 2% KOH/silica, silica) using hexane as a mobile phase.
The eluants were further separated using alumina column using
hexane and 10% dichloromethane/hexane (V/V) as a mobile phase.
The hexane was discarded while 10% dichloromethane/hexane was
further subjected to HPLC, porous graphitized carbon column clean-
up, and eluted with hexane. For DL-PCBs, PCDDS, and PCDFs, the
eluants from alumina column were further separated with active
carbon-silicagel impregnated column chromatography with 25%
DCM in hexane as a pre-fraction, which elutes DL-PCBs and toluene
Combustion
First Objective. Seven experiments (Exp-A to G) were conducted
for first objective (Table 1). For blank, in Exp-A paraffin was not
included and in Exp-B paraffin was included, fly ash was not used,
and the temperature was 300ꢀC (Table 1). From Exp-C to Exp-G,
paraffin powder and fly ash were included while temperatures were
adjusted to 100ꢀC, 200ꢀC, 300ꢀC, 400ꢀC, and 500ꢀC, respectively, for
Exp-C, D, E, F, and G (Table 1).
as a post-fraction elute PCDD/Fs. For PAHs analysis, 16 species of
13
Second Objective. Eight experiments (Exp-H to -O) were conducted
for the second objective with paraffin powder as a catalyst excluding
Exp-M. Nevertheless, HC1 concentrations were adjusted 10, 50, 100,
500, 1000, 100, 100, and 1000 ppm, respectively, for Exp-H, I, J, K,
L, M, N, and O (Table 2). An additional five experiments (Exp-P to
T) were conducted for the second objective with newspaper as a
catalyst and the difference in HCl concentration was 10, 50, 100, 500,
and 1000 ppm, respectively, for Exp-P, Q, R, S, and T (Table 3). Ten
more experiments (Exp-U to AD) were conducted with the presence
of fly ash and HC1 concentrations of 10, 50, 100, 500, and 1000 ppm
for paraffin powder and newspaper samples separately and the for-
mation of PAHs was monitored (Table 4).
C
-PAH standards were spiked to crude extract in a GC-vial and
12
analyzed directly. In case of any abnormal peaks in the sample, it was
further subjected to silicagel column cleanup and eluted with 10%
dichloromethane/hexane, evaporated, and purged under a gentle
stream of nitrogen gas. All the samples were analyzed using high-
resolution gas chromatography–high-Resolution mass spectrometry
(HRGC-HRMS), while BTX was analyzed by low-resolution mass
spectrometry (HRGC-LRMS). For analysis of HCN, the JISK0102
method was adopted. Particularly, a Flek-sampler bag gas chroma-
tograpgy-flame ion detector (GC-FID) was used and then a scanning
test was confirmed using GC-MS quadrapule.
Quantification and Identification
Third Objective. Eight experiments were conducted with blank
(without any sample), PE, PET, nylon, newspaper, PP, ABS, and
PVC, respectively (Table 5). All solid samples (PE, PET, nylon,
newspaper, PP, ABS, and PVC) were ground and filtered mechani-
cally and then particles of 1–3 mm in diameter were selected and used
for combustion.
A Micromass Autospec Ultima high-resolution mass spectrometer with
a Hewlett Packard (HP 6980) series gas chromatograph was used with
DB-5 MS (60 m, 0.32 mm, 0.25 lm) capillary column for the sepa-
ration of DL-PCBs and PCDD/Fs quantification and identification.

Formation of Chlorinated-Benzenes,-Phenols,-Dioxins,-Furans, PAHs, PCBs During Combustion of Various Catalysts
11
Fig. 3. Percentage evolution of
CO2 and O2 and concentration
(ppm) of CO in popypropylene
and polyethyleneterephthalate-
samples
The temperature conditions were as 150ꢀC for 1min. (20ꢀC/min) to
185ꢀC (1 min) to 3ꢀC/min to 245ꢀC (10 min) to 6ꢀC/min to 290ꢀC (14
min) for HRGC/HRMS. The interface temperature was programmed at
5–10ꢀC higher than the maximum value of each temperature program.
The carrier gas was helium with a flow of 1 ml/min. and the electron
impact ionization energy was 35–40eV. The MS was operated in se-
lected ion monitoring for each congener group at a resolution >10,000
(10% valley). Two ions were monitored for each isomer and congener
group. The recoveries of the 13C-labeled DL-PCBs, PCDD/Fs, PCBz,
PCPhs, and PAHs were greater than 75%. Toxic equivalency (TEQ)
concentrations were calculated based on I-TEF value. The concentra-
tions of BTX, HCN, precursors of PCBs and PCDD/Fs, and PAHs were
expressed as ng/g dry sample basis while TEQ of PCDD/Fs and DL-
PCBs represents pmol dry sample basis and CO was expressed on a
parts-per-million (ppm) basis (Fig. 3).
C). Particularly, paraffin powder did not show any impact on
the formation of chlorinated hydrocarbons (Exp-B), while fly
ash did (Exp-C). Among blank experiments, results in general
reveal a less pronounced increase of hydrocarbons (except
Dichlorobenzenes ‘‘DiCBzs’’). The Presence of DiCBzs in
blank experiments clearly shows the background concentra-
tions and, therefore, DiCBzs in experimental samples <450 ng/
g should be ignored. maximum chlorinated hydrocarbon con-
centration was noticed in Exp-F at 400ꢀC (Table 1). Total
concentrations of PCBz, PCPhs, PCDDs, and PCDFs on a
nmol or pmol basis are shown in square brackets in Table 1. In
general, the results indicate that the presence of paraffin
powder, fly ash, and 100-ppm HC1 concentration, and a 400ꢀC
temperature favor a l00 1000-fold greater formation of
chlorinated hydrocarbons. Formation of chlorine (on a
percentage basis) was slightly higher in Exp-E (Table 1).
Although an increased formation of chlorinated hydro-
carbons was observed, chlorine percentage showed less
pronounce ( 10 %). At 300ꢀC temperature, PCBz, PCPhs,
and PCDD/Fs showed maximum chlorine percentage.
Comparison with our earlier study with the paraffin pow-
der mixed with 0.5% NaCl and incinerated with various
temperatures produced elevated PCBz and PCPhs at
1050ꢀC (Fig. 4), while, combustion of PVC alone showed
concentrations similar to paraffin powder mixed with 0.5%
NaCl and incinerated at 600ꢀC or 750ꢀC (Fig. 4).
The homologue profiles of the PCBz, PCPh, PCDD, and
PCDF were different between experiments (Table 1). At
300ꢀC, T4CBz and T4CPh were higher, which corresponds to
the conversion of T3CBz at 400ꢀC and D2CBz or T3CBz and
MlCPh or D2CPh at 500ꢀC. Mono and or lower chlorinated
homologues of CBz, CPh, PCDD, and PCDF were compara-
tively higher in lower temperature conditions and or more than
400ꢀC. On the other hand, isomer profiles of CPhs were found
to be similar at all temperatures (Fig. 5) in which 2,4-D2CPh
formed maximum at all temperatures while 3,5-D2CPh were
minimum (Fig. 6). Wikstrom and Marklund (2000) demon-
strated that dominating CPh congeners were the 2,4,6-substi-
tuted congeners. Greater formation of 2, 4-D2CPh was
probably due to the ortho-para activating properties of the
Quality Assurance and Quality Control
Before each test run, the quartz tube with no sample was held at a
target temperature for 30 min, then air was passed in for 30 min,
which proceeding with nitrogen feed, and a blank test was performed
at the target temperature without sample. In order to maintain the
quality of the work, we used a disposable impinger for each sample
experiment. The quartz tube, impinger-connecting tubes, Amberliteꢁ
XAD compartment, and both of the furnace units were washed with
water, aceton, and toluene after combustion of each sample. In case
the inner surface of any parts did not become clear enough, it was
replaced with new parts. For every sample, complete combustion was
confirmed with flow meter and CO, CO2, and O2 monitor meters. CO,
CO2, and O2 monitor meters also functioned as a pump to release
unwanted gas or fumes from the apparatus. The incinerator setup was
carefully planned to suppress the influences of experimental condi-
tions except the waste composition.
Results and Discussion
Impact of Temperature
Concentrations of PCBz, PCPhs, PCDDs, PCDFs, and toxic
equivalency (TEQ) were minimum in the blank run (Exp-A to

12
T. Takasuga et al.
Table 1. Thermal formation of PCBz, PCPhs, PCDD/DFs, and TEQ (ng/g) with HCl, paraffin powder, and fly ash
Experment
A
B
C
D
E
F
G
Sample
HCl concentration
Fly ash
None
Paraffin
100 ppm
Absence
300
Paraffin
100 ppm
Presence
100
Paraffin
100 ppm
Presence
200
Paraffin
100 ppm
Presence
300
Paraffin
100 ppm
Presence
400
Paraffin
100 ppm
Presence
500
100 ppm
Absence
300
Temperature (ꢀC)
Chlorobenzene (Cl%/MW)
MlPCBz (0.316/113)
D2PCBz (0.483/147)
T3PCBz (0.587/182)
T4PCBz (0.657/216)
P5PCBz (0.705/251)
H6PCBz (0.747/285)
PCBzs [nmol.]
10
230a
22
10
10
10
450a
10
20
10
200
320a
150
13
10
41
190
210
120
50
120
310
1000 [5.5]
58
290
4300
10,000
15,000
14,000
6200
1200
37,000
65,000
41,000
23,000
5800
9300
10,000
9000
4400
1600
380
35,000 [230]
50
59
310
130
600
730 [5]
48
50,000 [230]
65
170,000 [920]
60
Cl%
Chlorophenols (C1%/MW)
Ml PCPhs (0.276/129)
D2PCPhs (0.436/163)
T3PCPhs (0.539/198)
T4PCPhs (0.612/232)
P5CPCPhs (0.666/267)
PCPhs [nmol.]
100
200
100
130
120
450
150
250
100
100
100
400
390
230
230
190
33
550
170
260
110
11
6700
3500
11,000
16,000
5500
25,000
26,000
45,000
46,000
5800
15,000
6000
1000
70
50
22,000 [160]
33
1100 [6.5]
44
1100 [7.1]
40
43,000 [220]
53
150,000 [800]
50
Cl%
PCDDs (C1%/MW)
TeCDDs (0.441/322)
PeCDDs (0.498/357)
HxCDDs (0.545/391)
HpCDDs (0.584/426)
OCDD (0.617/460)
PCDDs [pmol]
0.01
0.01
0.01
0.01
0.01
0.05
0.01
0.01
0.02
0.02
0.02
0.07
0.20
0.08
0.10
0.08
0.11
0.57 [0.002]
52
0.20
0.40
1.6
3.2
6.1
100
240
470
600
640
540
760
610
260
62
75
42
19
6.6
1.1
140 [0.42]
48
11 [0.027]
59
2100 [5]
57
2200 [6.1]
51
Cl%
PCDFs (C1%/MW)
TeCDFs (0.464/306)
PeCDFs (0.521/341)
HxCDFs (0.568/375)
HpCDFs (0.607/410)
OCDF (0.640/444)
PCDFs [pmol]
0.02
0.02
0.01
0.01
0.01
0.06
0.03
0.03
0.02
0.01
0.01
0.09
4.9
0.68
0.17
0.15
0.88
6.7 [0.02]
50
3.1
1.9
2.2
3.3
5.1
1400
1300
1100
850
420
5100 [14]
57
7300
5400
2700
970
170
17,000 [50]
51
1000
600
250
66
6.0
16 [0.04]
59
1900 [5.9]
50
Cl%
Total PCDD/DFs
TEQ (pmol)
0.10
0.16
7.3
0.10
27
0.20
7200
95
19,000
300
2000
32
a
HCl, hydrochloric acid; Background levels. PCBz, PCPhs, PCDDs, PCDFs, TEQ, and PAHs respectively, polychloro benzene, polychloro-
phenols, polychlorinated dibenzo-p-dioxins, dibenzofurans, toxic equivalency, and polycyclic aromatic hydrocarbon. The values were rounded.
OH- group in the phenol molecule generate CPhs, which
substituted 2,4,6-positions (ortho-para position). Furthermore,
before secondary formation at lower temperatures, the CPh
pattern is dominated by the (2,4-, 2,5-) substitutions. These
two isomers coelute in the analysis, but considering the pre-
valent ortho-para substitution, the 2,4-CPhs is much more
probable than the 2,5-CPh.
Changes within the PCBz and PCPhs levels and profiles/
caused by were secondary reactions. The PCBz and especially
P5CBz have the highest secondary formation of all studied
chlorinated hydrocarbons. Whether increased PCBz levels
originate from de novo synthesis or from chlorination of
available benzenes is difficult to conclude due to lack of
benzene and MICBz analyzes. Nevertheless, the CBz profile is
shifted from a dominance of D2 and T3CBz profile to a clear
dominance by P5CBz (Wikstrom and Marklund, 2000).
PCDD/Fs are also formed from natural woods and waste
woods by combustion. They are also formed from sodium
chloride (NaCl)-impregnated woods and a mixture of wood
and plastic wastes upon combustion. It appears that both or-
ganic and inorganic chlorides can be a precursor of PCDD/Fs
in incinerators. Ohta et al. (2002) reported PCDD/Fs can be
formed by heating air alone, presumably from trace amounts of
hydrocarbons and chlorine compounds contained in the air.
Other studies demonstrate PCDD/Fs formation was tempera-
ture-dependent in the range of 300ꢀC–500ꢀC, with the maxi-
mum observed around 300ꢀC (Shibata et al. 2003). The total
formation at 300ꢀC appeared high for PCDD/Fs in the exper-
imental range, and decreased with increasing temperature
(Stieglitz et al. 1989; Addink et al. 1991; Suzuki et al. 2004),
thus, this temperature region is given special attention. Greater
concentrations of chlorinated hydrocarbons at 400ꢀC in this

Formation of Chlorinated-Benzenes,-Phenols,-Dioxins,-Furans, PAHs, PCBs During Combustion of Various Catalysts
13
Table 2. Formation of PCBz, PCPhs, PCDDs, PCDFs, PAHs, and TEQ with varied concentrations of HCl and with the presence of fly ash and
parrafin powder as a catalyst
Experiment
H
I
J
K
L
M
N
O
Sample
Paraffin
10 ppm
Presence
Paraffin
50 ppm
Presence
Paraffin
100 ppm
Presence
Paraffin
500 ppm
Presence
Paraffin
1000ppm
Presence
Nothing
100ppm
Absence
Paraffin
100ppm
Absence
Paraffin
1000ppm
Absence
HCla concentration
Fly ash
Chlorobenzene (C1%/MW)
MlPCBz (0.316/113)
D2PCBz (0.483/147)
T3PCBz (0587/182)
T4PCBz (0.657/216)
P5PCBz (0.705/251)
H6PCBz (0.747/285)
PCBzs [nmol]
120
2600
1800
830
250
170
490
16,000
22,000
1400
4500
920
130
8500
33,000
20,000
7300
1300
70,000
61
23
4400
20,000
25,000
17,000
4800
200
8800
34,000
33,000
20,000
4300
10
230a
22
10
10
10
450a
10
20
10
85
670a
95
21
10
59
310
130
600
130
1000
5800
55
58000
58
71000
64
100,000
63
Cl%
Chlorophenols (Cl%/MW)
MlPCPhs (0.276/129)
D2PCPhs (0.436/163)
T3PCPhs (0.539/198)
T4PCPhs (0.612/232)
PSCPCPhs (0.666/267)
PCPhs [nmol]
5100
1300
330
110
150
7000
33
15,000
14,000
11,000
7100
1500
49,000
44
37,000
47,000
30,000
26,000
4200
2200
6800
24,000
27,000
9500
2600
5500
28,000
31,000
9800
100
200
100
130
120
450
150
250
100
100
100
400
600
1200
520
570
270
144,000
45
70,000
57
77,000
57
3200
Cl%
PCDDs (C1%/MW)
TeCDDs (0.441/322)
PeCDDs (0.498/357)
HxCDDs (0.545/391)
HpCDDs (0.584/426)
OCDD (0.617/460)
PCDDs [pmol]
6.0
2.5
0.86
0.30
0.17
10
250
210
150
53
13
680
50
290
310
240
86
18
940
50
290
630
830
570
250
2600
54
250
980
1100
790
320
3400
54
0.01
0.01
0.01
0.01
0.01
0.05
0.01
0.01
0.02
0.02
0.02
0.07
0.39
0.10
0.10
0.07
0.12
0.77
Cl%
47
PCDFs (C1%/MW)
TeCDFs (0.464/306)
PeCDFs (0.521/341)
HxCDFs (0.568/375)
HpCDFs (0.607/410)
OCDF (0.640/444)
PCDFs [pmol]
94
29
5.5
0.94
0.30
130
48
1800
1000
390
130
21
2400
1400
610
200
29
2900
2500
1500
710
180
7800
52
2900
2900
1400
730
170
8100
52
0.02
0.02
0.01
0.01
0.01
0.06
0.03
0.03
0.02
0.01
0.01
0.09
5.0
0.72
0.17
0.09
0.07
6.0
3300
50
4600
50
Cl%
Total PCDD/DFs
TEQ (pmol)
140
1.8
32
4000
62
27
5540
99
30
10,000
170
12,000
170
7.4
0.12
NA
28
0.20
NA
7200
95
NA
PAHsb
31
31
a
b
HCl, hydrolchloric acid; Background concentrations. Indicates lg/g concentration levels. PAHs, polycyclic aromatic hydrocarbons; NA, not
analyzed. The values were rounded.
study are probably due to the design of the incinerator or
the presence of paraffin powder. HCl, and fly ash. Many
studies have been reported on the generation and emission of
PCDD/Fs in municipal incineration and other combustion of
plastic resins, involving either homogeneous gas-phase reac-
tions or post- furnace processes involving fly ash. It has been
proven in previous experiments that the formation of PCDD/Fs
depends on temperature, and in these tests the temperature was
optimal for the formation of PCDD/Fs, at least after the gas
cooler, where it was from 350ꢀC to 444ꢀC (Asikainen et al.
2002).
This tendency is thought to be caused by the rapid formation
and slow decomposition of PCDFs, in addition to the relative
difficulty of their decomposition by oxygen. PCDDs were less
stable than confirmed by other measurements using fly ash and
analysis in MSWI's, where more PCDFs were present than
PCDDs (Addink and Altwicker, 1998). Other studies illustrate
that PCDFs tend to form dominantly in the high temperature
(e.g., combustion) zone and are successively trapped in the low
temperature zone. Especially, T4CDF is the most dominant
homologue contained in the wet zone and outlet gas. Another
study also indicated a high level of PCBz formation leads to
high levels of PCDFs formation (Ohta et al. 2004).
It is generally recognized that more PCDFs are formed than
PCDDs in combustion process such as in municipal solid waste
incinerators (Luijk et al. 1994; Addink and Olie, 1995; Weber
et al. 1999), which is also confirmed in this study (Table 1).
The ratio of PCDFs to PCDDs of the combustion gas is
known to be generally high. The high ratio of PCDFs to
PCDDs may be characteristic when combusting PVC. In the

14
T. Takasuga et al.
Table 3. Formation of PCBz, PCPhs, PCDDs, PCDFs, PAHs and TEQ with varied concentrations of HCl with the presence of newspaper and fly
ash as a catalyst
Experiment
P
Q
R
S
T
Sample
HCl concentration
Fly ash
Newspaper
10 ppm
Presence
Newspaper
50 ppm
Presence
Newspaper
100 ppm
Presence
Newspaper
500 ppm
Presence
Newspaper
1000 ppm
Presence
Chlorobenzene (C1%/MW)
M1PCBz (0.316/113)
D2PCBz (0.483/147)
T3PCBz (0.587/182)
T4PCBz (0.657/216)
H6PCBz (0.747/285)
PCBzs [nmol.]
330
3600
2600
1300
470
290
7200
13,000
9200
4600
36,000 [190]
60
380
1900
11,000
13,000
8100
120
4600
9800
10,000
8000
35,000 [170]
63
130
2600
4200
6500
7500
8400 [50]
55
37,000 [180]
64
25,000 [120]
65
Cl%
Chlorophenols (C1%/MW)
MIPCPhs (0.276/129)
D2PCPhs (0.436/163)
T3PCPhs (0.539/198)
T4PCPhs (0.612/232)
P5CPCPhs (0.666/267)
PCPhs [nmol.]
16,000
2200
550
180
55
19,000 [140]
31
5800
4500
10,000
7500
1700
30,000 [160]
50
6500
7400
18,000
10,000
2800
9200
10,000
18,000
11,000
3500
7400
9400
35,000
7400
4200
63,000 [340]
51
45,000 [240]
51
52,000 [280]
50
Cl%
PCDDs (C1%/MW)
TeCDDs (0.441/322)
PeCDDs (0.498/357)
HxCDDs (0.545/391)
HpCDDs (0.584/426)
OCDD (0.617/460)
PCDDs [pmol.]
37
28
16
6.7
3.5
91 [0.26]
49
62
130
210
170
140
710 [1.8]
55
61
200
350
320
290
57
140
350
380
450
32
98
290
480
910
1200 [3]
56
1400 [3.3]
57
1800 [4.2]
59
Cl%
PCDFs (C1%/MW)
TeCDFs (0.464/306)
PeCDFs (0.521/341)
HxCDFs (0.568/375)
HpCDFs (0.607/410)
OCDF (0.640/444)
PCDFs [pmol.]
95
35
11
730
530
310
170
53
1100
840
530
320
130
800
730
510
390
210
490
510
460
470
420
2.8
0.34
140 [0.45]
49
1800 [5.3]
52
2900 [8.5]
52
2600 [7.5]
53
2400 [6.4]
56
Cl%
Total PCDD/DFs
TEQ (pmol)
230
2.6
1.2
2500
36
2.2
4141
57
3.2
4100
51
2.2
4200
44
1.8
PAHsa
a
HCl, hydrochloric acid. Indicates lg/g concentration level. The values were rounded.
current study, all PCDF homologues were greater (especially
T4CDF over T4CDD) at all temperatures. Further more,
T4CDF to O8CDF homologues were greater at 500ꢀC com-
pared to T4CDD to O8CDD. Overall, temperature plays a
considerable role in the variation of homologue profiles. PCDF
were generally 5–10-fold higher than PCDD (Mininni et al.
2004), which is in good agreement with the conclusions by
Weber and Hagenmaier (1999) who found a l0-fold greater
PCDF over PCDD in exhaust gas. The higher formation can be
explained by the much higher level of PCDF present in flue
gas, which corresponds to an easier formation during chlori-
nation. Also, production of PCDF is supposed to proceed via
formation of main predibenzofuran structures (hydroxyl
biphenyls or hydroxylated dibenzo ethers), which lead to
chlorination dibenzofurans (Hell et al. 1997; Scholz, 1997;
Weber and Hagenmaier, 1997).
Impact of HC1 Concentration
Elevated concentrations of PCBz, PCDDs, PCDFs, and TEQ
were noticed, Exp-L (Table 2) whereas PCPhs were greater in
Exp-J. However, PAHs were homogeneous in all experiments.
Three blank tests (Exp-M to Exp-O) with the absence of fly
ash and presence and absence of paraffin powder at 100-ppm
and 1000-ppm HC1 concentrations were also conducted. The
results provided a very less pronounced formation of all the
target compounds (except D2PCBz). Concentrations of PAHs
were several hundred times greater than chlorinated hydro-
carbon analogues. This may be due to the greater proportion of
hydrocarbons in the gas stream of the test apparatus rather than
chlorinated compounds (Johansson and Bavel, 2003).
Homologue profiles of PCBz, PCPhs, PCDD, and
PCDF were different depending upon the HCl concentrations

Formation of Chlorinated-Benzenes,-Phenols,-Dioxins,-Furans, PAHs, PCBs During Combustion of Various Catalysts
15
Table 4. Concentrations of PAHs (ng/g sample) during burning of paraffin powder/newspaper with different HCl concentrations and fly ash as a
catalyst
Experiment
U
V
W
X
Y
Z
AA
AB
AC
AD
HCl concentration
Fly ash
10 ppm
50 ppm
100 ppm
500 ppm
1000 ppm
Presence
Presence
Presence
Presence
Presence
Sample
Paraffin Newspaper Paraffin Newspaper Paraffin Newspaper Paraffin Newspaper Paraffin Newspaper
Naphthalene
9000
6700
4500
2500
1800
1600
1400
1100
700
550
96
190
78
7
130
15
15
8
22
19
29
21
2.8
6
11,000 910
8400
6700
4100
2300
1800
1500
1500
1100
620
440
370
360
320
960
710
480
99
140
280
130
67
61
50
53
86
8000
6200
4600
2600
1700
2100
1600
1300
690
550
480
430
350
940
380
250
150
100
140
44
15
33
23
24
13,000 770
Acenaphthylene
Phenanthrene
Pyrene
9H-Fluorene
Fluoranthene
3600
3400
1900
1700
1500
1100
580
390
250
160
100
140
61
3700
4200
2200
1900
1700
1400
670
320
210
120
76
110
36
Anthrathene
Benzo[a]pyrene
Benzo[a]anthrathene
Benzo[g,h,I]perylene
Indeno[l ,2,3-cd]pyrene 430
Benzo[b]fluoranthene
Crysene
31
3
540
36
640
26
520
320
24
390
14
290
25
360
18
410
350
230
240
230
40
41
38
5.5
15
300
34
240
38
75
11
30
320
32
Acenapthene
Benzo[k]fluoranthene
170
150
5.8
16
220
220
240
260
230
210
3.8
12
Dibenzo[a,h]anthrathene 37
Total PAHs
0.96
32,000 1200
21
3.5
30
6.4
36
3.3
29
2.8
27,000 2200
30,000 3200
31,000 2200
31,000 1800
Hcl, hydrochloric acid. The values were added.
(Table 2). D2- and T3CBz were greater at 10 and 50 ppm HC1
concentrations, while increasing HCl concentrations yield an
increasing homologue profile that is similar to PCPhs but not
to PCDD/Fs (Table 2). Isomer profiles of chlorinated hydro-
carbons were found to be similar at all HCl concentrations
(results not shown). For example, D2CPhs do not have influ-
ence on HC1 concentrations especially for the 2,3-, 2,4-, 2,5,
2,6-, 3,4-, and 3,5- isomers. These results indicated that ortho
and para-orient reaction in chlorophenol ring might be a
possible explanation. On the whole, paraffin powder increased
greater formation of all target chemicals. In MSWIÕs, the
combustion gases generally include HCl at concentrations of
several hundred ppm or higher, originating from NaCl and
other chlorides commonly found in waste materials. It is be-
lieved this may lead to the formation of PCDD/Fs during the
incineration of materials having no chlorine (Lenoir et al.
1991).
PAHs were 2 to 10 orders greater when apply paraffin powder
as catalyst rather than the newspaper. TEQ concentrations were
several orders greater when combusting paraffin powder than
newspaper (Fig. 7). Especially, TEQ steadily increased from 50
ppm to 500 ppm HCl concentrations. At maximum HCl con-
centrations during the combustion of newspaper and fly ash,
TEQ slightly declined or were stationary. This was true in the
case of paraffin powder combust with fly ash.
The results also suggest a fly ash catalyzed PCDD/Fs for-
mation is a possible cause although there was a limit in dioxin
formation when ‘‘active chlorine site’’ in dioxin-free fly ash
was the only chlorine source. Furthermore, the presence of
chlorinated hydrocarbons may lead to form chlorinated com-
pounds. Therefore, fly ash is responsible for the formation of
PAHs rather than the HCl source. Particularly the ‘‘active site
control type reaction’’ in fly ash is a critical stage for the
formation of chlorinated compounds. For example, in the
heating chamber, the fly ash was greatly attracted by hydro-
carbons when compared to HCl. The time of reaction by
hydrocarbons might be comparatively longer than that of
chlorinated compounds. Consequently, heavier chlorinated
compounds had less chance to contract the ‘‘active reaction
site’’ in fly ash. Basically, in the fly ash ‘‘active site,’’ the
Deacon type of reaction can be expected in which the con-
tinuous back reaction of both CuCl2 and FeCl3 play a chlorine
source in experimental instrument. For instance, in case of
absence of a chlorine source (HCl acid), the Deacon reaction
will be restricted and, therefore, formation of chlorinated
compounds can be expected to be limited. For example, a 10–
50 ppm HCl concentration was not enough for the formation of
chlorinated hydrocarbons.
HC1 Concentration & Newspaper Catalyst
Uniform concentrations of PCBz were noticed (Exp-Q to Exp-
S) at all HCl concentrations except 10- and 1000-ppm (Ta-
ble 3), whereas, PCPhs, PCDDs, PCDFs, TEQ, and PAHs were
greater in Exp-R and Exp-S (Table 3). Again concentrations of
PAHs were several hundred times greater than chlorinated
hydrocarbon analogues. Wang et al. (2002) reported that PAH
were more predominant compounds than PCDD/Fs. Homo-
logue profiles of PCBz, PCPhs, PCDDs, and PCDFs were
similar to the experiment conducted with paraffin powder.
Concentrations of PCBz, PCPhs, PCDDs, PCDFs, TEQ, and

16
T. Takasuga et al.
Table 5. Concentrations (ng/g) of chlorinated hydrocarbons and PAHs during combustion of various polymers and newspaper
Sample
Blank
PE
PET
Nylon
Newspaper
PP
ABS
PVC
HC1
HCN
CO (ppm)
%CO2(V/V)
% O2 (V/V
584,000,000
<3000
170
0.40
20
<3000
13
<0.2
21
<3000
20
1.5
12,000,000
730
0.90
73,000
400
1.1
1,000,000
49
1.0
310
1.4
19
790
0.80
20
)
19
20
19
20
Total PCDFs
0.02
0.03
0.07
0.13
0.58
300
0.04
0.03
0.16
0.24
1.2
120,000
8400
0.14
0.17
0.12
0.43
4.3
0.01
0.06
0.08
0.15
0.23
0.15
0.15
0.53
0.07
0.05
0.18
0.29
0.01
0.06
0.08
0.14
0.59
650
12
3.4
0.19
16
130
Total PCDDs
Total Coplanar PCBs
Total PCDD/DFs + PCBs
TEQa
0.07
5.4
0.95
Biphenyl
170
17
130,000
13,000
<10
50,000
39,000
<10
2,800,000
170,000
<3000
780,000
270,000
3900
44,000
250,000
49,000
180,000
160,000
29,000
38,000
48,000
14,000
38,000
28,000
33,000
3700
370,000
14,000
<10
450
28
Dibenzofuran
Dibenzodioxin
Benzene
Toluene
Xylene
27
360
<10
<3000
<3000
<3000
10,000
<10
<10
590
500
360
60
130
<10
<10
50
<10
<10
<10
<10
<10
12,000
<10
<10
<3000
<3000
<3000
7600
<10
<10
260
410
260
61
120
<10
<10
37
<10
<10
<10
<10
<10
8700
<10
2,300,000
75,000
<3000
6400
360
62
580
860
280
360
200
58
68
100
22
22
18
<10
<3000
60,000
<3000
4300
26
100
1300
410
280
51
94
37
26,000,000
33,000
<3000
1,200,000
1,300,000
6800
130,000
670,000
140,000
490,000
380,000
85,000
95,000
140,000
45,000
140,000
86,000
120,000
9300
12,000,000
200,000
<3000
2,200,000
1,500,000
11,000
170,000
760,000
190,000
560,000
500,000
89,000
100,000
150,000
42,000
160,000
110,000
140,000
9000
730,000
38,000
<3000
2,600,000
1,400,000
13,000
220,000
940,000
240,000
520,000
620,000
120,000
130,000
180,000
58,000
170,000
140,000
130,000
14,000
7,500,000
Naphthalene
Acenaphthylene
Acenaphthene
9H-Fluorene
Phenanthrene
Anthrathene
Fluoranthene
Pyrene
Benzo[a] anthrathene
Crysene
Benzo[b] fluoranthene
Benzo [k] fluoranthene
Benzo[a]pyrene
Indeno[l ,2,3-cd]pyrene
Benzo[g,h,i]perylene
Dibenzo[a,h]anthrathene
Total 16 PAHs
20
40
<10
<10
<10
<10
<10
6700
11
<10
9400
5,000,000
6,700,000
2,000,000
PE, polyethylene; PET, polyethyleneterephthalate; PP, polypropylene, ABS, Acrylonitrile butadiene styrene; PVC, polyvinylchloride; TEQ,
a
Toxic Equivalent Quantity. pgTEQ/g basis. The values were rounded.
Fig. 4. Homologue distribution of PCBz and
PCPhs in paraffin powder mixed with 0.5% NaCl
and PVC at varied temperatures
Overall, the results of this study in general indicated that
HCI and unburnt hydrocarbon with the dioxin-free fly ash
formed PCBz, PCPhs, and PCDD and PCDFs. Especially, the
formation of PCDD and PCDF even at 100ꢀC and suggested
the dioxin-free fly ash had catalytic reaction and, therefore,
pronounced formation (Table 1). Based on our results, we can
emphasize that the Deacon type of reaction explains the in-
creased formation of most of chemicals, namely;
2R ꢀ H þ 2½CuCl2 or FeCl3ꢁ þ ðOÞ d 2R ꢀ Cl
ð1Þ
þ 2½CuCl or FeCl2ꢁ þ H2O

Formation of Chlorinated-Benzenes,-Phenols,-Dioxins,-Furans, PAHs, PCBs During Combustion of Various Catalysts
17
Fig. 5. Homologue distribution of PCBz and
PCPhs in fly ash at varied temperatures
Fig. 6. Isomer abundance (%) of dichlorophenols
in fly ash at varied temperatures
superior mechanical and chemical properties and is used for
various types of moldings. Disposal of PVC is being re-
duced by recycling; however, municipal and industrial
wastes still contain a large quantity of PVC. PVC can be
decomposed easily combustion, and acts as a chlorine
source for the formation of PCDD/Fs (McNeil et al. 1998).
Furthermore, fly ash in incinerator contains significant
amounts of basic PCDD/DF precursors, PCBz and PCPhs,
in particular, at concentrations one order of magnitude
higher than those of PCDD and PCDF. These precursors are
strongly bound to fly ash. At 250–400ꢀC, they become
important components of de novo synthetic reactions
yielding PCDD, PCDF, and PCB on solid particles con-
tained in flue gas. During PCDD and PCDF formation, the
reactivity of PCPhs is much higher than that of PCBz (Bures
et al. 2003). Very reactive phenols can also be transformed
into PCDF and PCDD via their condensation reactions
(Grabic et al. 2002), in contrast to PCBz dehalogenations
(Bures et al. 2003).
2½CuCl or FeCl2ꢁ þ 2HCl þ ðOÞ d 2½CuCl2 or FeCl3ꢁ
þ H2O
ð2Þ
Furthermore, the presence of metal chloride in the fly ash
and hydrocarbons in the gas stream found major contribu-
tors for the increased chlorinated hydrocarbons. Chlorine
gas is also reported to generate by Deacon reaction between
oxygen and HCl acid. CuO is considered to be an oxygen
source and also a catalyst (Born et al. 1993; Froese and
Hutzinger 1996a,b). It has also been reported that the for-
mation of PCDD/Fs in mixture samples of carbon and fly
ash was repressed in a condition where there was no oxy-
gen, such as nitrogen in atmosphere (Addink and Olie,
1995). Chlorine is necessary for the formation of PCDD/Fs.
Municipal and industrial wastes generally contain chlori-
nated compounds such as NaCl, KCl, and PVC that can
react as a chlorine source in the incinerators (Stieglitz et al.
1989, 1996; McNeil et al. 1998; Stieglitz 1998). PVC is
considered one of the compounds most responsible for the
formation of PCDD/Fs in waste incinerators. PVC has both
Irrespective of temperature and HC1 concentration, homo-
logue profiles of PCDD/Fs were dominated by low chlorinated
analogues (Tables 1 and 2). Mininni et al. (2004) reported

18
T. Takasuga et al.
Fig. 7. Toxic equivalency estimation (PCDD/
DF-TEQ) when burning paraffin powder and
newspaper at varied HCl concentrations
similar results in pilot incineration tests of sewage sludge
spiked with organic chlorine. As for as their discussions,
homologue profile depends on after burning temperature.
Experimental tests at different oxygen concentrations show
that oxygen deficiency leads to the formation of PCDF, and
especially P5CDF and T4CDF. On the contrary, when oxygen
increases a higher formation of PCDD occurs. Corresponding
to our study, Yasuhara et al. (2001) reported that the amount of
dioxins formed in the samples according to the number of
chlorides was P5CDD>T4CDD>H6CDD>H7CDD>O8CDD
in PCDD isomers and T4CDF>P5CDF>H6CDF>H7CDF and
O8CDF in PCDF isomers.
Higher levels of copper in the waste are associated with de-
creased CO concentration in the flue gas, which means that
copper promotes combustion. This suggests that the amount of
other products of incomplete combustion (PICs) should also
decrease with increasing copper. Figure 3 shows the range of
CO concentrations and CO2, O2 consumption contributions
(%) from polypropylene (PP) and polyethyleneterephthalate
(PET). There is no difference in the O2 and CO2 contribution
in both samples. However, the CO concentration was greatly
enhanced in PP suggesting different combustion pathways
exist between two polymers. It is known that water is generally
involved in CO combustion, and it is therefore possible that
water generated in the PP substrate combustion contributed to
the lowering of the CO concentrations during the coated film
combustion. The CO peak observed in PP suggests the
occurrence of a two-step combustion reaction, with the first
step comprising a dehydrochlorination reaction accompanied
by CO and CO2 generation and formation of the residue, and
the second step comprising its gradual oxidation (Ohta et al.
2004). As is also evident from Figure 3, the O2 consumption
was higher during the PP combustion than during the PET
combustion, in stoichiometrical correspondence with the
presence of the PP substrate.
Blank analysis was performed prior to polymer/newspaper
combustion experiments (Table 5). The results showed a for-
mation of detectable limits of few target compounds. The
concentrations of HC1, HCN, PCDFs, PCDDs, DL-PCBs,
TEQ; BTX, precursors such as biphenyl, dibenzodioxins,
dibenzofuran, and 16 polycyclic aromatic hydrocarbons
(PAHs) are also shown in Table 5. The blank study was con-
ducted without fly ash and, thus, the results were considered to
be a theoretical formation of the thermo-chemical process. The
HCN formation was explained to be nitrogen containing
compounds such as ABS and nylon. The HCN concentration
levels were reasonable. However, levels in PP likely to be
formation from additive hindered amine anti-oxidant pro-
cesses. The study of Mingjim PiaoÕs pyrolysis experiment
(Piao et al. 1999) demonstrated that PAHs were formed at an
incinerator temperature of 900ꢀC due to the aliphatic hydro-
carbons was converted as PAHs with benzene ring. The for-
mation of PCBz has also been determined during combustion
HCl Concentration: Catalysts and PAHs
Formation of PAHs was maximum irrespective of the experi-
ments with different catalysts as well as HCl concentrations
(Table 4). Particularly, monochlorinated derivatives of naph-
thalene, acenaphthalenes, and phenanthrene concentrations
were predominated, while acenaphthene and dibenzo[a,h]anth-
rathene showed lower concentrations. Similar findings were also
observed after combustion of PVC (Wang et al. 2003). Com-
paratively, paraffin powder produced 30 times greater concen-
trations of PAHs than newspaper (Table 4). Based on these
results, it can be explained that chlorinated compound formation
was greatly influenced by the catalytic reaction of fly ash. Fur-
thermore, the presence of hydrocarbons may lead to form
chlorinated compounds at a considerable level. Therefore, fly
ash is responsible in the formation of PAHs when compared to
the HCl source. Particularly, the ‘‘active site control type reac-
tion’’ in fly ash is a critical stage for the formation of polycyclic
aromatic compounds. The time of reaction by hydrocarbons
might be comparatively longer than chlorinated compounds.
Consequently, heavier chlorinated compounds had less chance
to have contact with the ‘‘active reaction site’’ in fly ash.
Combustion of Polymers
The CO concentration is usually used as a practical parameter
for indicating changes in combustion conditions in a furnace.

Formation of Chlorinated-Benzenes,-Phenols,-Dioxins,-Furans, PAHs, PCBs During Combustion of Various Catalysts
19
of PVC (Ahling et al. 1978). These results were compared with
our study and the results imply that PE, PP, nylon, and
newspaper formed elevated levels of BTX and PAHs. Partic-
ularly, benzene, naphthalene, acenaphthalene found to be lg/g
levels, the Benzo[a]pyrene with lg/g levels. The lower levels
were found for PET, ABS, and PVC with 1/4000-fold less
levels. It is probable that the presence of oxygen in PET might
impact the low formation of PAHs.
by nylon (6700 lg/g), PE (5000 lg/g), and news paper
(2000 lg/g). PVC, PET, and ABS showed the PAHs concen-
tration as less than blank levels (Table 5). In a previous study
(Johansson and Bavel, 2003), the sum of 16 USEPAÕs PAHs
was found to vary from 480 to 3590 lg/kg. The amounts of
carcinogenic PAHs were between 89 and 438 lg/kg ash. The
maximum levels of carcinogenic PAHs exceed the Swedish
generic guidelines for sensitive land use.
We also determined the precursors of PCBs, PCDD/Fs, in
order to understand the formation mechanism of DL-PCBs and
PCDD/Fs. It should be worth indicating that DL-PCBs and
PCDFs were detected in all the samples while PCDDs were
less than 10-ng/g. It is assumed that chlorinated dioxins might
have formed during the reaction of the chlorophenol dimer-
ization effect (Takasuga et al. 2002a,b). These results indi-
cated that the formation mechanism of PCBs and PCDFs was
different from PCDDs. The formation of PCB and PCDF could
be explained as a pyrolysis effect and the formation of chlorine
from the carbon skeleton might be a suitable explanation.
In terms of the TEQ and homologues of PCDD/Fs and DL-
PCBs, in nylon, ABS levels were similar to blank levels and,
therefore, nylon, ABS concentration considered to be negli-
gible. The PE, PP, and PET levels were slightly higher but
considered to be equal to the blank due to the background
levels (e.g., incinerator contamination). The elevated levels of
TEQ in PVC were considered to the influence of Cl contents
which is 57% of parent compound and thus 1 to 100- million
of chlorinated aromatics occur to form during this stage.
Nevertheless, these values are several magnitudes less when
compare to the parent Cl contents. Some reports indicated
PCDD/Fs contributed more than 90% (on average 97.3%) to
the total TEQ in the stack emission, suggesting a minor impact
of DL-PCBs from combustion sources on the total environ-
mental TEQ burden.
A group of compounds that are known to be present in
bottom ash are chlorinated polycyclic aromatic hydrocarbons
(Cl-PAHs). Several Cl-PAHs are regarded as priority pollu-
tants by the US Environmental Protection Agency (USEPA)
and the European Environment Agency (EEA). They known to
be persistent in soil, have low biodegradability, high lipophi-
licity, and some are carcinogenic to humans (IARC, 1987).
Naphthalene and phenanthrene as the most abundant PAHs in
all samples (Fangmark et al. 1993; Johansson and Bavel, 2003)
in one of the UK study, most abundant individual PAH was
benzo[g,h,i]perylene. PAHs are strongly bound to ash and are
not released to the environment during deposition on a small-
scale open air landfill.
Chlorinated poly cyclic aromatic hydrocarbons (Cl-PAHs)
are released from combustion of polyvinylchloride (PVC) at
different furnace temperatures. PAHs formation from the
combustion of PVC polymer was greater at the furnace tem-
perature of 900ꢀC than at 600ꢀC (Wang et al. 2002). The result
shows that the species and the levels of Cl-PAHs increased
with increasing furnace temperatures within the experimental
range of 600–900ꢀC. Furnace temperature, airflow, the burn-
ing time and the combustion duration have an effect on the
levels of Cl-PAHs in the emissions from PVC combustion.
During combustion under high temperature, HCl is first re-
leased from PVC, and then PAHs are produced in the cooler
zone of the furnace by cyclisation reaction of gaseous hydro-
carbon fragments formed by incomplete combustion. But the
PVC burning with a flame, which can be observed, started
approximately at 4s (900ꢀC) and 45s (600ꢀC) after the boat
containing PVC plastics was positioned in the oven. Due to
this delay of PVC burning with decreasing furnace tempera-
ture, most HCl may leave along with airflow, and a tempera-
ture-dependent equilibrium between HCl and Cl2:2HCl (g)
+ 1/2 O2 fi Cl2 (g) + H2O (g) can shift to the reverse reaction,
thus reducing the opportunity of PAHs exposure to Cl2.
Therefore, less Cl-PAHs formation was found at a lower fur-
nace temperature of 600ꢀC (Wang et al. 2003).
Interest has been focused on Cl-PAHs since some of them
have also been shown to have stronger toxicity and mutagenic
properties than their corresponding PAHs in test systems for
biological activity. Lofroth et al. (1985) found that 7-chloro-
benzo[a]anthracene and 6-chlorochrysene showed strong di-
rect mutagenic effects. The latter compound has also been
shown to have a high affinity to the tetrachlorodibenzo-p-di-
oxin (TCDD) receptor (Toftgard et al. 1985) and to be a potent
aryl hydrocarbon hydroxylase (AHH) inducer (Franzen et al.
1988). Concentrations of benzo[a]anthrathene and 6-chloro-
chrysene were not influenced by any concentrations of HC1
(Table 4). When combustion various polymers, PE, nylon,
newspaper and PP produced higher PAHs but toxic PAHs were
less than other analogues (Table 5).
Our earlier study concluded (1) materials without chlorine
but with the presence of fly ash as a catalyst produce PCDD/
Fs, (2) inorganic and organic materials in the furnace were a
major chlorine source of HCl to form PCDD/Fs, (3) the
observations also proved that PCDD/Fs also formed with the
presence of NaCl burning with dioxin-free fly ash apart from
PVC, and (4) it is quite apparent that chlorinated chemicals
such as PCBz, PCPhs, and PAHs are major chemicals that
evolve during heating of dioxin-free fly ash catalytic reaction
rather than PCDD/Fs and their toxic equivalency (TEQ)
(Takasuga et al. 2000, 2002a,b, 2003).
Impact of HC1 concentration, paraffin powder, and fly ash
as a catalyst on the formation of PAHs was prominent.
Especially in all HCl concentrations, total concentrations of
16-PAHs were 26.7 to 31.5 lg/g sample (Table 2). However,
instead of paraffin powder when newspaper was used as a
catalyst, PAHs concentration declines in all 5 HC1 concen-
trations (1.2 to 3.2 lg/g sample) (Table 3). Consequently,
paraffin powder and newspaper have been employed sepa-
rately to see the formation difference (Table 4). Concentra-
tions of PAHs were several magnitudes greater in paraffin
powder (27 to 32 sample) than in newspaper (1.2 to 3.2 lg/g
sample). Combustion of polymers yielded concentrations of
PAHs several magnitude greater than combustion of HC1 and
catalyst alone. Particularly, PP produced 7500 lg/g followed
In the current study, with our experimental conditions,
400ꢀC with paraffin powder, 100 ppm HCl concentration, and
fly ash formed a large amount of PCBz, PCPhs accompanied by
a small amount of PCDFs and PCDDs. Furnace temperature

20
T. Takasuga et al.
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and air supply and fly ash had an influence on the formation of
these toxic organics. An HCl concentration of 1000 ppm pro-
duced significant amount of PAHs followed by PCBz, PCPhs
but less PCDFs, PCDDs. Instead of paraffin, when newspaper
was used as a catalyst, a 500-ppm HCl concentration yielded
greater PAHs, PCBz, PCDFs, and PCDDs. On the other hand,
different concentrations of HCl, paraffin powder, and news-
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tween PAHs. However, paraffin powder produced a greater
amount of PAHs than the newspaper. Furnace temperature and
air supply had a greater influence on the formation of target
compounds. These results suggest that metal chlorides are
possibly the main factors in the formation of PCDD/Fs from the
incinerator, although speculative effects of other metal chlo-
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various polymers prevailed. PVC showed greater PCDD/Fs,
DL-PCBs and TEQ. Nylon and PP showed greater precursors
of PCBs, PCDD/Fs, and PAHs, while PE had greater benzene
concentrations. The results of experiments with PP, PET, and
PE, indicate that fly ash, temperature, and de novo synthesis of
PCPhs play a primary role in the formation of PCDD/Fs during
combustion of these non-chlorinated polymers.
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