Page 37 - Plastics News November 2025
P. 37
FEATURE NEWS
CAPTURING CO WITH RECYCLED HOUSEHOLD PLASTICS
2
rials make up a sizable portion of real household
plastic waste.
Preparing Waste Samples
In an experiment to assess the effectiveness
of AC from real household waste, researchers
sourced common waste materials. Polyethyl-
ene bags (LDPE), milk containers (HDPE), food
wrappings (PP), packaging foam (PS), and plas-
tic bottles comprised the household waste sam-
ple. Material preparation included dissolving the
ixed plastic waste can be transformed PS foam to remove air bubbles and cutting the
into activated carbon through micro- other plastics into small pieces. The researchers
Mwave pyrolysis, improving CO capture mixed the plastics, then subjected them to high
2
and recycling efficiency. temperatures in a vertical tubular furnace, pro-
ducing the char. The researchers used both con-
Pyrolysis, a process that converts plastics to val- ventional thermally assisted chemical activation
uable products, produces a solid char. This char and microwave-assisted activation to produce
is a precursor to develop activated carbons (AC), ACs. Potassium hydroxide (KOH) was the activa-
which can remove a wide variety of environmen- tor used in this process.
tal contaminants. Studies have shown success in
developing plastic-waste derived ACs from pol-
yethylene terephthalate (PET) and polystyrene
(PS). During the recycling of plastics, separation
and sorting materials is complex and can be ex-
pensive. Household waste includes many types
of plastics. Developing porous carbons for CO2
capture from mixed plastics could make this pro-
cess more accessible.
Mixed Waste, Mixed AC Feasibility
Pure plastic wastes, such as low- and high-den- Researchers prepared the samples, then used
sity polyethylene (LDPE, HDPE) and polypro- two different methods of preparing the ACs to
pylene (PP) cannot produce ACs. During their compare their effectiveness. Image courtesy of
carbonization, these materials only produce oils Household mixed plastic waste derived adsor-
and gases, with no recovered char. These mate- bents for CO2 capture: A feasibility study.
November 2025 PLASTICS NEWS 37
