Plastic Is a Gas

The latest buzz from the big multinational bottlers is plant plastics. Giants like Coke and Pepsi have unleashed a flurry of press releases touting this "green" invention. And self-professed green blogs eat up the writings of PR/marketing departments as fact. Or worse, misunderstand the facts, spreading misinformation.

From www.acleanpeace.com -- in an article that gets
its facts badly wrong about Pepsi's new product

So is this invention actually green? Set aside the logic of locking nature's nutrients and compost into polymers that nothing in nature will break back down. Just look at the argument that plastic from plants reduces our use of fossil fuels.

Since plastic is petroleum-based, switching to plants will free us of a major source of petroleum dependency, right?

Wrong.

There's a lot of confusion & spin about this, and it's time to clear that up. #1, #2, #4, and #5 plastic comes from ethane. Ethane is a waste by-product found in natural gas fields and oil wells. It is a volatile, hot-burning natural gas. It is so unstable burns so hot that, by U.S. & UK law, it must be separated and removed from the methane that constitutes "normal" natural gas before that methane is piped around the land. And we've all seen images of oil refineries flaring off gas:

Gas flare in Thailand
(picture from Wikimedia Commons)

That's ethane (p. 6 in the PDF file). It's so useless to this refiner that it's just burned right into the air. Junk.

As the plastics industry was being born in the years leading to World War II, someone learned that ethane can be converted to ethylene (and propylene) by steam-cracking. Basically, a hydrocarbon like ethane is mixed with steam, then flash-heated in an oxygen-free furnace to a very high temperature. By tweaking the temperature & hydrocarbons, you can come out with a whole laundry list of petrochemicals. But most of what you get is ethylene & propylene. These can then be polymerized into the polyethylene that makes up #1, #2, and #4 plastics, or the polypropylene that makes up #5. **

At last, some refiners finally had an outlet for all that ethane. (Though as the picture above makes clear, the world still produces far more of it than can be used.)

In short: Nobody drills an oil well to make plastic. Nobody fracks a gas field to make plastic. Plastic comes from the unavoidable, and otherwise mostly unusable, waste by-product of fossil fuel refining. If plastic were suddenly, miraculously removed from the world tomorrow, not one well or field would close shop.

Steam-cracking is energy intensive. There's an agument that getting plastic from plants is less so. That somehow this reduces fossil fuel use. There's two problems with this line of reasoning:

1. The science is secret; there's no way to know how much energy it really takes to convert plant matter all the way into polymers.
2. There's also no breakdown of how much energy it takes to grow the plant material. Agriculture is extremely energy intensive. Stocks must be planted, fertilized, weeded, watered, harvested, dried, processed, transported -- all of which is only to make yet another plastic bottle.

Creating plastic from plants is not about being green, being responsible. It's about being seen as green & responsible. So far, traditional journalism has been far too complacent in helping the process. Don't get fooled.

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** Ethylene is also a precursor to creating PVC (#3 plastic), and ethane is now even being used to create styrene, from which #6 plastic, polystyrene, can be produced.

Deconstructing a Greenwash

Amid the tragedy unfolding in Japan this week, a press release from PepsiCo caused some buzz.

Full text at: http://www.pepsico.com/PressRelease/PepsiCo-
Develops-Worlds-First-100-Percent-Plant-Based-
Renewably-Sourced-PET-Bott03152011.html

Sounds wonderful. Plant-based packaging! Great, right? That's about as "green" as it gets?

No. Not even close. Let's deconstruct this.

Claim #1: This "enable[s] the company to manufacture a beverage container with a significantly reduced carbon footprint."

Reality: According to the plastics lobby itself, the natural gases used to make plastic are a byproduct of petroleum drilling/refining. By not capturing these gases as plastic, instead they'll either be flared off or burned as another fossil fuel. Sourcing plastic from plant matter does not appear to lower the amount of fossil fuels currently being drawn from the earth or reduce the carbon footprint of production.

Claim #2: "PepsiCo's 'green' bottle is 100 percent recyclable and far surpasses existing industry technologies."

Reality: The plastic made by this new process is #1 polyethylene terephthalate, the same exact #1 plastic that currently goes into these bottles. As explained in the "Triangle Is a Lie" trilogy, #1 plastic recycling is a downward spiral. Walk down your neighborhood grocery aisle. Look at all the #1 bottles of soda/water/juice. Find -one- that says "Made Using Recycled PET." Recycling a plastic bottle back into a food-worthy mirror of itself is extremely hard, because of contamination and the breakdown that happens to PET when it is crushed, remelted, and remolded. Recycling a "plant-based" PET bottle doesn't change this. For every single bottle of PET bought, 100% new virgin PET usually has to be created to replace it on the shelf. Plastic recycling is not a closed loop. It was never meant to be. It only offers a very cheap feedstock for recyclers (mostly in developing nations) who want to create lower-quality products from the free labor of citizens who recycle.

Claim #3: "By... using its own agricultural scraps as feedstock for new bottles, this advancement should deliver a... win for the environment."

Reality: PepsiCo wishes to take organic plant material and turn it into plastic. Switchgrass, pine bark, corn husks -- and eventually orange peels, potato peels, and oat hulls. All of these are compostable materials -- materials that can break down back into the building blocks needed to renourish depleted soils. But instead of maintaining a healthy and natural soil cycle, Pepsi wants to strip much of these building blocks away from nature and turn them into nondegradable plastic, which will persist in the environment for centuries or millennia. If it's ecologically unfriendly to use fossil fuels as plastic, it is folly to use nature's own perfect fertilizers as plastic.

Pepsi is correct about one thing, however. This is a momentous achievement. Because it now means that, even if some future society has been able to wean itself completely from fossil fuels, companies will still be able to keep churning out all the plastic our oceans can handle.

Business as usual.