recycling and reuse of plastics contained in waste …athens2014.biowaste.gr/pdf/triantou_pr.pdf ·...
TRANSCRIPT
National Technical University of Athens
School of Chemical Engineering
Polymer Technology Lab.
RECYCLING AND REUSE OF PLASTICS
CONTAINED IN WASTE FROM
ELECTRICAL AND ELECTRONIC EQUIPMENT
Μ.Ι.Triantou, P.A.Tarantili, A.G. Andreopoulos
2nd International Conference on Sustainable Solid Waste Management, Athens, Greece, 12-14 June, 2014
World plastics production 1950-2012Source: Plastics Europe-Plastics – The Facts 2013: An analysis of
European latest plastics production, demand and waste data
European plastics demand by segment 2012Source: Plastics Europe
Plastics production and demand
Global production of plastics in 2012 rose to 288 million tones – a 2.8% increase compared to 2011.
In Europe, in line with the general economic situation, plastics production decreased by 3% from 2011 to 2012 reaching 57 million tones.
In 2012: demand in Europe decreased by 2.5% and
reached 45.9 million tones, the electrical and electronic equipment sector
covered the 5.5% of the european plastics demand.
2
Disposal, recycling and energy recovery
of plastics in 2012 in Europe
(Source: Plastics Europe)
Waste management of plastics
The total recovery of plastics increased by 4% in 2012 (mechanical recycling increased by 4.7%, energy recovery increased by 3.3%).
At the same time, there was a reduction of 5.5% of landfilled plastics.
Total plastics waste recycling and recovery 2006-2012 in Europe(Source: Plastics Europe)
Treatment of post consumer plastics waste 2012 by
EU-27+2 (Source: Plastics Europe)
In Greece, recycling and energy
recovery rates are still at low values.
3
Waste management of EEE
The waste coming from EEE represents an about 8% of the total municipal waste internationally.
In European Union, 12-20 kg WEEE/habitant is produced each year and their overall, annual production varies between 6.5-7.5 million tones [Hellenic Solid Waste Management Association].
In Greece, 170.000 tones WEEE are produced per year [Hellenic Solid Waste Management Association]. During 2005-2013 (1st semester), the 87.73% of EEE was treated, whereas the 12.27% was
led to landfill in Greece [Appliances Recycling S.A.].
Total exploitation of WEEE (tones) and separate collection WEEE from
domestic sector (kg/habitant) during 2005-2012 in Greece
(Source:eoan -Report of recycling in Greece, September 2013, Athens, 18-22)
33411 tones
exploited
4
Composition of WEEE
47,90%
20.60%
7%
5,40%
4,70%
4,60%3,10%
2,60% 2% 1% 0,90%
iron-steel
plasticscopper
glass
aluminium
other
circuits
wood
ceramics
other metals
rubberComposition of WEEE (Source: Hellenic Solid Waste
Management Association)
Packaging dominates the waste generated from plastics, covering 62.2% of the total. Other applications like building and construction, electrical and electronic products and agriculture count for 5 till 6% each [Plastics Europe] .
Source: WRAP, 2009
Generation of post-consumer plastics
waste by application (Source: Plastics Recyclers Europe)
ACR
6%
PA
4%
PEP
3%
HIPS
2%PET
2%POM
2%
PE
2%PVC
2%Άλλα
4%
DMPS
3%
PB
3%
PC/ABS
3%
ABS
20%
PP
10%
PS
12%PC
11%
SAN
10% 5
Materials
ABSABS
PPPCCl30B Cl30B
Poly(acrylonitrile-butadiene-styrene) terpolymer, ABS (Terluran GP-35, BASF)
Polycarbonate, PC (Makrolon 2805, Bayer)
Polypropylene, PP
Cloisite 30B (OMMT) (Rockwood Clay Additives GmbH)
2 phr
100/0
70/30
50/50
30/70
0/100
2 phr
ABS PC Cloisite 30B
Organic modification
of Cloisite 30B
PP 6
contributes to the
improvement of
properties of blends
acts as a compatibilizer
between the
components of blend
a low-cost, ecological additive
Experimental procedure
Pre-mixture
Melt intercalation (co-rotating, twin screw extruder)
Granulation Injection
Melt Flow Index
(MFI)
Thermogravimetric
Analisis (TGA)
Gross Calorific
Value (GCV)
Tensile
testDynamic Mechanical
Analisis (DMA)
7
Melt Flow Index (MFI)
The incorporation of organoclay into the ABS/PC blends results in a decrease of the MFI, maybe due to the confinement of polymer chains motion, caused by organoclay platelets and tactoids, and the interactions between the polar groups of ABS and oxygen containing groups of Cloisite 30B.
The MFI of ABS/PP blend tends to be decreased by incorporating OMMT.
70/30 50/50 30/700
2
4
6
8
10
12
14
16
18
MF
I (g
/10
min
)
ABS/PC (w/w)
0 phr Cl30B
2 phr Cl30B
PC
100/0 70/30 50/50 30/70 0/1000
1
6
8
10
12
14
16
MF
I (g
/10
min
)
ABS/PP (w/w)
0 phr Cl30B
2 phr Cl30B
8
The ABS/PC blends exhibit higher MFI than that of PC.
ABS exhibits lower MFI than PP and ABS/PP blends presents melt behavior closer to that of PP.
Blending of polymers is the key for the improvement of their processability.
Tensile test
The tensile strength of ABS is increased by the addition of PC, whereas it is decreased significantly by the addition of PP.
In ABS/PC blends, the tensile strength seems to follow the rule of mixture. In ABS/PP blends, the tensile strength is closer to that of pure PP. The incorporation of organoclay in ABS/PC blends seems to cause a slight increase in the
tensile strength.
In ABS/PC blends, a synergic action between the two polymers is observed for Young’s modulus.
In ABS/PP blends, the Young’s modulus is decreased as the PP concentration is increased. The addition of organoclay significantly improves the Young’s modulus of the examined
blends. The enhancement of stiffness is interpreted by the higher modulus of organically modified
clay and by the low deformability of polymeric chains penetrating the silicate galleries.
100/0 70/30 50/50 30/70 0/10025
30
35
45
50
55
60
65
70
Ten
sile
str
en
gth
(M
Pa)
(w/w)
0 phr Cl30B/ABS/PC
2 phr Cl30B/ABS/PC
0 phr Cl30B/ABS/PP
2 phr Cl30B/ABS/PP
100/0 70/30 50/50 30/70 0/1001250
1500
1750
2000
2250
2500
2750
Yo
un
g's
mo
du
lus
(MP
a)
(w/w)
0 phr Cl30B/ABS/PC
2 phr Cl30B/ABS/PC
0 phr Cl30B/ABS/PP
2 phr Cl30B/ABS/PP
9
+ 4-13.5%: ABS/PC
+ 14-23.5%: ABS/PP
Dynamic Mechanical Analysis (DMA)
-100 -50 0 50 100 150 2000.00E+000
5.00E+008
1.00E+009
1.50E+009
2.00E+009
2.50E+009
3.00E+009
Sto
rag
e m
od
ulu
s (P
a)
T (oC)
100/0 ABS/PC
70/30 ABS/PC
50/50 ABS/PC
30/70 ABS/PC
0/100 ABS/PC
-120 -90 -60 -30 0 30 60 90 120 1500.00E+000
5.00E+008
1.00E+009
1.50E+009
2.00E+009
Sto
ra
ge m
od
ulu
s (P
a)
T (o
C)
100/0 ABS/PP
70/30 ABS/PP
50/50 ABS/PP
30/70 ABS/PP
0/100 ABS/PP
-120 -90 -60 -30 0 30 60 90 120 1500.00E+000
5.00E+008
1.00E+009
1.50E+009
2.00E+009
2.50E+009
3.00E+009
Sto
ra
ge m
od
ulu
s (M
Pa
)
T (o
C)
30/70 ABS/PC
2 phr Cl30B/30/70 ABS/PC
30/70 ABS/PP
2 phr Cl30B/30/70 ABS/PP
A synergistic effect is observed for ABS/PC blends and the greatest value is recorded for 50/50 w/w composition.
Below 10 oC, the ABS/PP blends present higher storage modulus than that of neat ABS and lower than or equal to that of neat PP. On the contrary, over 10 oC, the Gʹ of ABS/PP blends is higher than that of neat PP and lower than that of neat ABS.
The ABS/PC blends present higher storage modulus than that of ABS/PP blends.
The incorporation of organoclay leads to an impressive increase of storage modulus, in comparison with this corresponding to unreinforced blends.
10
PC
ABS blends
25 oC
ABS
PP
Thermogravimetric Analysis (TGA)
250 300 350 400 450 500 550 600 650-0.025
-0.020
-0.015
-0.010
-0.005
0.000
Deriv
ati
ve o
f w
eig
ht
ch
an
ge (
%/o
C)
T (oC)
100/0 ABS/PC
70/30 ABS/PC
50/50 ABS/PC
30/70 ABS/PC
0/100 ABS/PC
300 350 400 450 500 550 600-0.020
-0.015
-0.010
-0.005
0.000
Deriv
ati
ve o
f w
eig
ht
ch
an
ge (
%/o
C)
T (oC)
50/50 ABS/PC
2 phr Cl30B/50/50 ABS/PC
30/70 ABS/PC
2 phr Cl30B/30/70 ABS/PC
The thermal stability increases with the following order: ABS<PP<PC.
In ABS/PC blends, the thermal degradation mechanism takes place in one stage, whereas in ABS/PP blends it involves two stages.
The incorporation of clay platelets in PC-rich ABS/PC blends turns the thermal degradation mechanism to a two stages process and leads to higher values of char residue.
The OMMT seems to inhibit thermal degradation of the PC phase, which might be due to the creation of new paths of the degradation reaction and to the formation of a protective layer of nanoclay at the ABS/PC interface.
300 325 350 375 400 425 450 475 500
-0.025
-0.020
-0.015
-0.010
-0.005
0.000
Deriv
ati
ve o
f w
eig
ht
ch
an
ge (
%/o
C)
T (oC)
100/0 ABS/PP
70/30 ABS/PP
50/50 ABS/PP
30/70 ABS/PP
0/100 ABS/PP
1st stage 2nd stage
11
Gross Calorific Value (GCV)
ABS/PC ABS/PP8000
8200
8400
8600
9800
10000
10200
10400
GC
V (
cal/
/g o
rgan
ic m
ate
ria
l)
50/50 w/w
0 phr Cl30B
2 phr Cl30B
100/0 70/30 50/50 30/707500
7750
8000
8250
8500
9000
9250
9500
9750
10000
10250
10500G
CV
(cal/
g o
rgan
ic m
ate
ria
l)
ABS/PC (w/w)
0 phr Cl30B
2 phr Cl30B
As the PC content in ABS/PC blends increases, a reduction of GCV is observed, due to the poor burning characteristics of PC as compared with ABS.
The incorporation of OMMT to ABS/PC or ABS/PP blends does not have a significant effect.
Emissions from hazardous substances in WEEE (heavy metals, halogens, organic components like brominated and chlorinated flame retardants) complicates the technical aspects of energy recovery.
The GCV increases with the following order: PC < ABS < PP.
12
Conclusions
The addition of PC in ABS matrix improves its thermomechanical properties, whereas the addition of ABS in PC matrix makes feasible its processing at lower temperatures.
The addition of PP in ABS matrix increases its thermal stability, whereas the addition of ABS in PP matrix improves its mechanical behavior.
The incorporation of OMMT to ABS/PC or ABS/PP blends leads to an increase of their melt viscosity, improves significantly the Young’s modulus and the storage modulus and protects the PC phase during the thermal decomposition of PC-rich, ABS/PC blends.
The blending of polymers used in WEEE is an appropriate procedure for their common management, which eliminates the time consuming and costly phase of sorting.
The incorporation of organoclay to polymer blends is a low-cost and environmentally friendly alternative technique for the upgrading of their performance during their mechanical recycling.
13
Future Research
14
Thorough investigation capability of Cloisite 30B to improved compatibility and performance of ABS/PC and ABS/PP blends.
Extension of the study to other polymeric blends with various components (e.g. PC/SAN).
Upgrading of the examined plastic blends by the incorporation of the appropriate amount of additives (e.g. carbon nanotubes, graphene) as advanced technology reinforcing fillers.
National Technical University of Athens
School of Chemical Engineering
Polymer Technology Lab.
RECYCLING AND REUSE OF PLASTICS CONTAINED IN
WASTE FROM ELECTRICAL AND ELECTRONIC
EQUIPMENT
Μ.Ι.Triantou*, P.A.Tarantili, A.G.Andreopoulos
2nd International Conference on Sustainable Solid Waste Management, Athens, Greece, 12-14 June, 2014
Thank you very much
for your attention
*e-mail: [email protected]
16
Temperature at six zones of extruder (oC)
1st 2nd 3rd 4th 5th Die
(100/0 w/w) ABS/PC 210 200 200 195 195 190
(100/0 w/w) ABS/PC* 190 195 195 200 200 205
(70/30 w/w) ABS/PC 230 215 215 210 210 205
(50/50 w/w) ABS/PC 240 235 235 230 230 225
(30/70 w/w) ABS/PC 260 255 255 250 250 245
PC 290 280 275 270 265 260
Temperature at six zones of extruder (oC)
1η 2η 3η 4η 5η Die
0/100 ABS/PP 180 180 185 185 190 190
30/70 ABS/PP 190 190 195 195 200 200
50/50 ABS/PP 190 190 195 195 200 200
70/30 ABS/PP 190 190 195 195 200 200
100/0 ABS/PP 190 195 195 200 200 205
Screw speed:200 rpm
ABS is composed of :44% acrylonitrile42% styrene14% butadiene
17
50/50 ABS/PC nanocomposite
According to SEM this nanocompositeconsists of a continuous ABS phase and a dispersed PC phase.
Clay tactoids are arranged mainly on the ABS/PC interphase and in the ABS phase
It is possible the formation of a physical crosslinking network structure composed of clay particles and polymeric chains which limitates the chains’ motion and protects them during the thermal degradation.
The heat barrier effect could also provide superheated conditions inside the polymer melt leading to extensive random scission of polymer chain and evolution of numerous chemical species which, trapped between clay layers, have more opportunity to undergo secondary reactions. As a result, some degradation pathways could be promoted leading to enhanced charring.
The clay may permit radical recombination reactions, exerting thus a stabilization effect in the ABS/PC/layered silicate nanocomposite.
The dispersion of organoclay layers leads to the formation of a tortuous path which inhibits the passage of volatile degradation products during the initiation of thermal degradation (labyrinth effect).