Polyethylene terephthalate (PET) is a thermoplastic polymer resin of the polyester family and is used in synthetic fibers, beverage, food and other liquid containers, thermoforming applications and engineering resins. Depending on its processing and thermal history, PET may exist both as an amorphous and as a semi-crystalline polymer. Polymerization is through a polycondensation reaction of the monomer ethylene terephthalate with water as the byproduct.The majority of the world's PET production is for synthetic fibers with bottle production accounting for around 30% of global demand. The polyester industry makes up about 18% of world polymer production and is third after polyethylene (PE) and polypropylene (PP). Mechanical recycling of PET becomes more and more economically valuable due to the growing environmental awareness of the (Western) customer. The possibility of using recycled PET which will come into contact with food creates the need to develop efficient and sensitive analytical methods applicable to the identification and quantification of contaminants from recycled PET, which would also evidence that this recycled material complies with the terms of legislation. The recycling processes of PET for direct food contact have to evidence efficiency of contaminant removal and ensure consumer protection.

1. Looking for a reliable approach
to screen recycled PET pellets
Dr. Joeri Vercammen
Managing Expert IS-X
www.is-x.com

2. 2007: 11.400.000 tonnes
Source: www.foodproductiondaily.com

3. 2012: 14.800.000 tonnes
Source: www.foodproductiondaily.com

4. 2017: 19.100.000 tonnes
Source: www.foodproductiondaily.com

5. Source: www.petcore-europe.org
120.000.000.000 bottles in 2012.

6. Source: www.petcore-europe.org
52% recycled.

7. Polyester fibers.
In 2011, 39% of all recovered
European PET was used
to produce polyester fibers.

8. Packaging.
In 2011, 25% of the European RPET
was used to make containers
(food & non-food).

9. Eco pallets.
The PET industry continuously
looks for new applications
for reclaimed material.

10. Develop a method that is capable of
assuring the quality of recycled PET for
applications in the food industry.

11. Most interferences coming
from other plastics, flavour
compounds, inks, etc.

12. Current state-of-the-art

14. About 3,720,000 results (0.39 seconds)

15. SFE
GC/MS
Pyrolysis
GC/MS
Liquid
GC/MS
Headspace
GC/MS

16. SFE
GC/MS
Pyrolysis
GC/MS
Liquid
GC/MS
Headspace
GC/MS

17. SFE
GC/MS
Pyrolysis
GC/MS
Liquid
GC/MS
Headspace
GC/MS

18. SFE
GC/MS
Pyrolysis
GC/MS
Liquid
GC/MS
Headspace
GC/MS

19. SFE
GC/MS
Pyrolysis
GC/MS
Liquid
GC/MS
Headspace
GC/MS

20. Headspace techniques

21. Static Headspace Injection
□ Classic hardware
□ GC/MS friendly
□ Robust
□ Limited sensitivity

22. Solid Phase Microextraction
□ “Classic” hardware
□ On-line and off-line
□ Enrichment technique
□ Not quantitative

23. Direct Thermal Extraction
□ Dedicated hardware (TD unit)
□ Fast
□ Automated
□ Risk of contamination

24. Microchamber/Thermal Extraction
□ Dedicated hardware (TD unit + µ-CTE)
□ Off-line procedure
□ Quantitative
□ Reference method

25. Results and discussion

26. Standards & samples
□ Megamix (Restek, # 30601)
□ Ten PET samples
□ Virgin
□ Recycled OK
□ Recycled NOK
□ Blend virgin/recycled

27. Hardware
□ Thermo Trace 1300 GC
□ Thermo ISQ single quadrupole MS
□ Thermo Triplus RSH
□ Markes TD-100 thermal desorption system
□ Markes µ-CTE 250
□ SPME fibers (30 µm PDMS, Supelco)

28. Software
□ Thermo Trace Finder
□ AMDIS deconvolution sw

29. Static headspace
□ Sample weight : 5 g
□ Equilibration : 30 min @ 150 °C
□ Volume : 1 mL
□ Split ratio : 30:1
Insufficiently sensitive to discriminate between
the various PET samples.

30. Solid phase microextraction
□ Sample weight : 1 g
□ Sampling : 30 min @ 150 °C
□ Injection : splitless
Insufficiently sensitive to discriminate between
the various PET samples.

31. Direct thermal extraction
□ Sample weight : 0.1 g (PTFE sleeve)
□ Tube desorption : 20 min @ 220 °C
□ Trap : general purpose
□ Split ratio : 250:1
Fast system contamination.
Limited reproducibility.

32. Microchamber/thermal extraction
□ Sample weight : 5 g
□ Extraction temp : 200 °C
□ Sampling : 40 min @ 50 mL/min
□ Sampling tube : 100% Tenax

33. Microchamber/thermal extraction
□ Sample weight : 5 g
□ Extraction temp : 200 °C
□ Sampling : 40 min @ 50 mL/min
□ Sampling tube : 100% Tenax
□ Tube desorption : 20 min @ 220 °C
□ Trap : general purpose
□ Split ratio : 500:1

34. Virgin PET
RT: 0.00 - 19.03
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
Time (min)
0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
RelativeAbundance
12.71
14.03
14.63
14.89
18.3815.28 15.93
16.20
17.26
12.37
13.89
13.29
4.58
11.45
12.16
10.81
9.64
8.243.28 9.60
2.94 10.33
9.14
7.69 8.615.70
4.83 7.547.12
3.42 5.13 6.042.04 3.96
6.24
NL:
3.58E7
TIC MS
02082011_
sk52
1,2-Ethanediol
phthalate

35. RT: 0.00 - 19.03
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
Time (min)
0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
RelativeAbundance
13.89
15.7415.08 15.93
16.68 18.18
4.59
13.83
3.28 13.52
13.31
9.16 12.8612.242.97
10.405.71
6.06 8.26 10.877.714.853.44 8.52 9.677.012.83
NL:
2.21E7
TIC MS
02082011_
sk55
Recycled OK
1,2-Ethanediol
4(1H)-Quinazolinone

36. Recycled NOK
RT: 0.00 - 19.03
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
Time (min)
0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
RelativeAbundance
12.60
7.35
13.86
10.39
3.31 17.2413.05 15.894.63 14.8412.427.60 17.8911.767.896.06 9.856.865.15 9.892.95 3.44
NL:
9.06E8
TIC MS
02082011_
sk70
Limonene
Benzofuran
Benzoic acid, 3-methyl-

37. RT: 0.00 - 19.01
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
Time (min)
0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
RelativeAbundance
18.7810.32
15.13
18.42
15.34
14.52
11.77
16.43
14.23
13.84 15.894.60 17.23
17.53
8.71
13.3611.07 13.06
3.30
12.769.53
8.26
9.38
7.817.42
2.11
2.95 6.85
4.98
5.71
4.49 5.82
NL:
1.91E7
TIC MS
02082011_
sk78
Blend
Limonene

38. Conclusions

39. Looking for a solution to screen PET pellets?

40. Looking for a solution to screen PET pellets?

41. Looking for a solution to screen PET pellets?
Microchamber/thermal extraction
GC/MS in full scan/SIM mode
AMDIS deconvolution

42. Need assistance or advice?
Just give me a call or sent me an email.
j.vercammen@is-x.com
010/45.00.25