The Sirius Effect: 

Using waste streams to create new products is not a new idea, but bringing this idea to life often comes with surprises and challenges. This is the case with finding new sources for surfactants, using waste oils as our source:
could we find a commercially viable way to do that?
This was the challenge that Sirius set forth at the beginning of the year - and our interns for this year delivered.

These newsletters often discuss sustainable production or biodegradable products as ways to reduce our impact on the planet. Recycling often gets left out, in part because it’s not always immediately apparent how it would be done. Recently, Sirius started investigating recycling waste oils as the basis for our Ethoxybrite line of ethoxylated fatty acids. Academically, it seemed promising, but until now the practical proof was lacking.

Recycling waste oil is currently the process re-refining leftover oil and reusing it, burning it as biodiesel. Biodiesel may be renewable, but it still generates CO2. The process of turning waste oil into something which is useful beyond burning it to CO2 - surfactants - is considerably more difficult. This is complicated by the fact that waste oils are often a mix of different fats, with varying carbon chain lengths. Surfactants are best made using carbon chains of length C12-C14, as these can be readily dissolved in water but still have the power to emulsify dirt varying impurities also present a challenge.  

Four interns worked on this project. They analyzed the fatty acid profiles in samples taken from waste streams of the agricultural, cosmetic, oleo-chemical and food industries. They then worked out two methods to turn those fatty acids into surfactants. They were able to achieve yields as high as 98%, though yields around 80% were more typical. One key takeaway from this investigation is that not every waste stream is suitable for this process; one sample turned out to be nearly unusable, given the low amounts of suitable fatty acids. 

The other key takeaway is that this is an economically viable process. The cost analysis showed that, with the proper waste stream, the cost per metric ton of C12/C14 surfactant is similar to some typical non-ionic surfactants. And because these are (relatively) local waste streams, international shipping issues have no role in determining availability. If you are interested in partnering with Sirius to make this process mainstream, let us know. Together, we can work to reduce our reliance on palm oil and make the most of what we already have.

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