Recycling of plastic (CH7) Flashcards
(8 cards)
1
Q
Annual production of plastic
A
400 M tonnes
2
Q
what are the 3 R’s
A
reduce reuse recycle (mech or chem)
3
Q
3 problems of recycling
A
- collection
-sorting
-reducing contaminents = washing
4
Q
Different aspects of sorting
A
based on density = direct
fractions (metal removal, tracers, markers, fingerprints)
5
Q
Describe mechanical recycling
A
doesn’t allow chemical structure
6
Q
Con’s of mechanical recycling
A
thermal degradation (UV)
time and T = change molar mass
7
Q
Describe chemical recycling
A
alters chemical structure
pyrolysis (thermal cracking)
gassification (^T, low O2 amount to avoid comb)
depolymerization (if reversible)
8
Q
target waste materials + product for the chemical recycling
A
waste mat: PE, PP, PS
product: oil to replace fossil oil in crackers
