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Hello and happy almost Friday day!

Today we are going to talk about the process of deriving carbon from annually-renewable resources for synthesis into bio-based polymers. As per yesterday’s discussion, substituting bio-based carbon for petro-based carbon provides a value proposition in the context of material carbon footprint for plastic packaging.

Slide 7: Carbon Footprint Basics—Value Proposition

Consider the following chemical process for manufacturing traditional, fossil-based plastics:

Fossil feedstock (oil, coal, natural gas)-->Naptha-->ethylene/propylene-->polyethylene (PE), polypropylene (PP)

Now, consider the process of manufacturing bio-based plastics from a renewable feedstock:

Bio/renewable feedstock (crops and residues i.e. corn, sugarcane, tree plantations i.e. lignocellulosics, algal biomass i.e. algae)-->BIO monomers, sugars, oils (continue)

These BIO monomers, sugars and oils can then be synthesized into EtoH, which is then used to make ethylene/propylene, the building blocks of PE and PP;

OR, these BIO monomers, sugars and oils can be synthesized to make PLA and PHA.

The difference between something like PLA and the PlantBottle, therefore, is that the PlantBottle derives its carbon from biomass, as explained in the process above, yet has the same chemical composition as tradition, petro-based PET. Therefore, it is not designed to “biodegrade” in an industrial composting facility or others, whereas PLA, which is of a different chemical composition though it derives its carbon from, like the PlantBottle, an annually renewable source, is designed to “biodegrade” in the intended disposal environment as stipulated by the manufacturers of PLA. Check out the molecular structures of PLA vs. PP on the 7th slide of Narayan’s presentation; as you will see, the carbon, highlighted in red, can come from petro-based or bio-based feedstocks. Cool, huh!?!

Slide 8: Understanding the value proposition for bio carbon vs. petro/fossil carbon

Narayan then went on explaining the difference between old carbon (fossil fuel) and new carbon (crop residue/biomass). Consult the 8th slide of the PPT for an explanation of how old carbon is synthesized from new carbon.

Consider the following processes of synthesizing new vs. old carbon:

CO2 (present in atmosphere) + H20-->photosynthesis (1-10 years)--> (CH20)x +O2-->NEW CARBON (biomass, forestry, crops)

Vs.

C02+H20-->photosynthesis (1-10 years) -->(CH20)x-->-->-->(10,000,000 years)-->OLD CARBON (fossil resources i.e. oil, coal, natural gas)

He then argued that all the criticism about manufacturing plastics out of non-renewable sources is misplaced because it doesn’t really matter where you get the carbon from—be it old or new carbon. The issue, however, is the rate and scale at which we have been taking old carbon (oil) out of the earth: it is inherently unsustainable to continue to derive carbon from fossil fuel for synthesis into disposable plastic packaging because it takes millions of years to create old carbon from the process described above, whereas it takes just 1-10 years to derive new carbon from crop residue/biomass.

Does that make sense?

He concludes: “Rate and time scales of CO2 utilization is in balance using bio/renewable feedstocks (1-10 years) as opposed to using fossil feedstocks.”

Goodness!

Hello everyone!

Another gloomy day in Chicago—I can’t wait to go to San Diego next week for the Sustainable Packaging Coalition’s spring meeting! AND, I just booked flights to Rogers, Arkansas, for the Walmart SVN meeting and Expo. Though Dordan is not exhibiting this year, I am excited to see what other vendors are offering and get updated on Walmart’s sustainability initiatives!

So I am about half way through TerraCycle CEO Tom Szacky’s book, “Revolution in a Bottle.” It is really, really good, and inspiring! I thoroughly suggest you get yourself a copy today! That which I like so much about his story is his awareness into the economic realities of the market place: one of his main arguments is that the majority of consumers will NOT pay more for a green product; while everyone wants to do well by the environment, few are willing to pay for it. His whole approach, therefore, is to be able to provide green products at a competitive price and performance as those currently on the market. And the best way to do that? Use what is considered waste as your feedstock. BRILLIANT.

I met with TerraCycle’s VP of Global Brigades today to learn more about the logistics of their approach to recycling/reusing hard-to-recycle materials and products. Basically, they have a brand pay to finance the brigades (collection of materials and shipment) and in return, TerraCycle upcycles or recycles the collected materials thereby extending the brand’s life post consumer. It’s a win-win: the brand gets consumers to participate in their identity by collecting it’s waste i.e. Capri-Sun bags, thereby strengthening the consumers relationship with the brand and the brand’s perceived environmental stewardship; the collected “waste” is then recycled/upcycled into new products, further extending the life of the brand and/or creating a value-added product for the market while diverting hard-to-recycle materials from landfill! From how I understand it, TerraCycle is privatizing waste management—cutting out the MRF, brokers, municipalities, etc, and creating a simplistic supply chain based on consumers’ willingness to participate and a team of innovative designers. As discussed numerous times in my Recycling Report, the whole problem with recycling thermoforms is the high cost of manual sortation and the lack of investment in automated sorting technologies. If consumers are doing the sorting themselves at places where people congregate i.e. schools, church, retailers, etc, then the whole issue of manual vs. automated sorting systems at a MRFs is totally bypassed. These materials don’t even make it to the MRF—TerraCycle sort of IS the MRF! Crazy, right?!?!

The wheels are churning upstairs for sure!

So let’s discuss the first part of Narayan’s PPT on the science of biodegradable polymers. Please visit March 16ths post to download the presentation and follow along with my descriptions per slide number.

Part one: Bio-based products concepts

Slide 6: What value proposition to bio-plastics offer?

As discussed in March 16ths post, there are two components to “sustainability” as it pertains to packaging: the carbon footprint of the package and the end of life management of the packaging material. Therefore, today’s discussion will focus specifically on the carbon footprint dimension of the multi-faceted conception of “sustainability.”

Narayan began the first part of the workshop by explaining that bio-based polymers, that is, plastic that derives its feedstock from an annually-renewable resource, like starch, provides a value proposition in the context of material carbon footprint. He states: “Switching from the “petro/fossil” carbon in plastics to “bio-renewable” carbon reduces the material carbon footprint.”

He then went into a discussion of LCA, as many in the industry have argued that petro-based polymers are “better” than bio-based due to the energy-intensive process of creating carbon from bio-based resources as opposed to petro-based resources. And here is what he had to say:

This has nothing to do with the PROCESS. Those who manufacture bio-based polymers must ensure that their process of generating polymers from renewable resources is better than or equal to the existing process of creating polymers from fossil fuel. However, this isn’t your or my problem. I am not advocating that the process of creating plastic from crop residue is not important when understanding the “sustainability” of these non-traditional resins; I am arguing that that discussion is a separate one then the discussion we are having right now, which is understanding how substituting petro-based carbon with bio-derived carbon is a value added proposition in the context of material carbon footprint.

In a nut shell: there is a value proposition in switching from petro-based carbon to bio-based carbon for plastic material feedstock. This value proposition has nothing to do with the manufacturing process of petro vs. bio-based polymers; it has to do with switching from a non-renewable source of carbon to an annually renewable one. If carbon in polymers can originate from non-renewable fossil fuel or annually-renewable crop residue, why not substitute the renewable carbon with the non-renewable!?!

But how do you derive carbon from crop residue for synthesis into bio-based polymers?

Tune in tomorrow for Chemistry 101.