MATERIALS | TECHNOLOGY RECYCLING
Phthalate plasticisers improve electrochemical recycling of PVC
Researchers at the Univer- sity of Michigan in the USA have devised a way to recycle PVC electrochemi- cally – using phthalate plasticisers within the material to drive the reaction. “PVC is the kind of plastic that no one wants to deal with because it has its own unique set of prob- lems,” said Danielle Fagnani, co-author of a paper on the research in Nature Chemistry. “PVC usually contains a lot of plasticisers, which contami- nate everything in the recycling stream and are usually toxic. It also releases hydrochloric acid really rapidly with some heat.” When PVC is mechani-
cally recycled, the heat used in the process can
MARINE PLASTICS Manufacturing plastic from marine waste
LG Chem has entered into an agreement with Netspa to build a system that recycles marine waste into new plastics. It will allow LG Chem to secure raw materials for its Seokmun
National Industrial Park pyrolysis oil plant – which is scheduled to begin operations in 2024. Once Netspa sorts and processes plastics from marine waste, LG Chem will use it to make recycled plastics. The companies hope the partnership will protect the marine ecosystem and reduce carbon emissions. Around 50,000 tonnes of marine wastes – such as discarded fish
nets – are generated every year in South Korea. However, collecting this is difficult and expensive. Therefore, most was uncollected – or incinerated. The partners believe that plastics made in this way will have
one-third the carbon emissions of a product made the conventional way. �
www.lgchem.com
www.filmandsheet.com January/February 2023 | FILM & SHEET EXTRUSION 47 IMAGE: DANIELLE FAGNANI
cause plasticisers to leach out of the material and into the recycling stream, say the researchers. In addition, hydrochloric acid is released – which can corrode equip- ment and threaten worker safety. To find a way to recycle
PVC that did not require heat,
the researchers looked at electrochemistry – and found that the presence of plasticis- ers helped to improve the efficiency of the process. “We found that it still
releases hydrochloric acid, but at a much slower, more controlled rate,” she said. Using electrochemistry –
rather than heat – introduces an electron into the system, which gives it a negative charge. This breaks the carbon-chloride bond in PVC, producing a negatively charged chloride ion. Controlling the rate at which electrons are introduced into the system helps to control how quickly hydro- chloric acid is produced. The acid produced can be used by industries as a reagent for other chemical reactions. The chloride ions can also be used to chlorin- ate small molecules called arenes – which can be used in pharmaceutical and agricultural components. Fagnani says the study shows how scientists might think about chemically recycling other materials. �
https://umich.edu
IMAGE: LG CHEM
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72
