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> extruded polymers like plastic bags, wraps and containers are almost always synthesized from waste products of fossil fuel refinement That's almost completel
by 08-15 5y ago
> extruded polymers like plastic bags, wraps and containers are almost always synthesized from waste products of fossil fuel refinement
That's almost completely false.
It obviously depends on the kind of plastic. PE and PP are made from ethene and propene, which are indeed byproducts of fuel refining. But demand far outstrips supply now, so these are now made on purpose. PS is made from styrene, which is not a byproduct. It is made from low-value chemicals, so it's upgraded waste. PET is made from terepthalic acid, which is very much not a waste product of any process.
Even if there were any waste products from fuel refining, they would certainly not be vented. They'd be burned as fuel. Which is also a sensible thing to do with waste plastics. (Someone is going to object that this releases CO2. It does. Burning fuel releases CO2. We can come back to this point once we longer burn coal or methane for energy.)
- bobiny 5y agoWiki and some other sources say that PE is made from crude oil byproducts https://extension.psu.edu/how-plastic-is-made-from-natural-gas https://extension.psu.edu/how-plastic-is-made-from-natural-g...
- dmitryminkovsky 5y agoThank you for the check. > PE and PP are made from ethene and propene, which are indeed byproducts of fuel refining. When we're talking about things like plastic bags and wraps, aren't we talking about PE/PP? > Even if there were any waste products from fuel refining, they would certainly not be vented. They'd be burned as fuel. This makes a lot of sense. But what if a refinery is not equipped to do this? What if the refinery is in a place with poor or non-existant environment regulation/enforcement? > But demand far outstrips supply now, so these are now made on purpose. This is the kicker. So how do we make PP/PE when supply of precursors from crude refinement is not sufficient? > PS is made ... PET is made from ... I shouldn't have used the word extruded, I guess? I was thinking more about PE/PP.