Green Chemistry: From the Bench Top to Industry, A Chemical Engineer’s Perspective

By Cynthia Cheung, Member-at-Large for the GCI

As a chemist, do you ever think about how to scale up your chemical reactions, or your chemical processes? For most of us, the answer is no. However, this idea of industrial scale is something that is constantly addressed in the Chemical Engineering and Applied Chemistry department. Consequently, the 12 Principles of Green Chemistry become fundamental to scale up a reaction from the bench top in a research lab to mass production in a chemical plant (Figure 1).

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Figure 1. Example of a chemical plant design [1]

For me, the biggest difference I have found moving from the Chemistry department to the Chemical Engineering department is that the principles of Green Chemistry are not concepts that Chemical Engineers often have to think about or address, because these principles are integrated and engrained into their work as objectives and limitations. A process can be thrown out simply because it uses columns for purification (which cannot be done on a large scale, because you would need truckloads of solvent) or because one of the reagents is toxic.

As a chemist, we do what works and worry about alternatives after we have established what we targeted. So pause and think about it for a second: can you continue what you’re doing and upscale it from milligrams to tonnes? Even theoretically speaking, if you could produce that much product, would that process make sense? For example, would that Stille coupling reaction be safe when you’re using tonnes of tin2, or could you afford to be using or making catalysts when you need tens of kilograms of it? So how to do you go about engineering your process so that it would be suitable for industry? Rather, how do the engineers do it?! Well, broadly speaking (and from asking around) a few of the main considerations that seem to be in common are:

Cost Analysis

How much are all of the reagents and solvents going to cost, and where are there substitutes for cheaper alternatives?

Rate of Reaction

How long is this reaction going to take? Because time is money.

Waste

How much waste is produced, what type of waste and is it recyclable? Also to keep in mind is if the waste is hazardous, then what alternatives can be used from the beginning to avoid any hazardous waste generation? In addition, if there’s pollution, then that also has to be reduced or eliminated altogether.

Work up

This consideration is often tricky, as most organic labs usually use techniques that are not scalable (I’m looking at those purification columns). In addition to that, side products and by-products are also something that often can give engineers a headache. Atom economy is very important for industry, as it lessens the amount of waste produced, and also aids in producing a good product yield.

Energy Consumption

How much energy is required for a reactor and for a chemical plant to run is also part of the cost analysis for a process. It would definitely be preferential to be using less energy (so lower temperature reaction conditions and reactions that generate no heat). Essentially, if all reactions could be at room temperature, that would be perfect.

So with these considerations in mind, could you re-engineer your synthesis?

 

References:

[1] http://en.citizendium.org/wiki/File:FCC.png

[2] Stille, J. Palladium Catalyzed Coupling Of Organotin Reagents With Organic Electrophiles. Pure and Applied Chemistry 1985, 57.

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Green Chemistry Applied In Industry: Our 2015 Symposium

By Karl Demmans, 2015 Symposium Coordinator for the GCI

Following the success over the past couple years with our workshops entitled “Future Leaders in Green Chemistry” and “Next Steps in Green Chemistry Research”, we felt that the next logical step after teaching chemists how to apply green chemistry in their own research would be to have a symposium highlighting how these techniques are implemented by the chemical industry in the working world. Therefore we focused on obtaining lecturers from industries across Canada and the United States such as Xerox, VWR, Sigma Aldrich, Dow, 1366 Technologies, Proteaf Technologies, Green Chemistry & Commerce Council, and many more.

Starting off the event was Dr. Andy Dicks’ Crash Course which covered the basics of green chemistry while incorporating industrial case studies from recent years. The industrial lectures followed over two full symposium days, covering a variety of topics with three main goals: 1) how companies are bridging the gap between academia and industry, particularly by adopting promising chemistry from academia, 2) how companies are connecting with each other globally to instill better practices such as industrial transparency through environmental sustainability reports, and 3) chemical synthetic case examples exploring the diverse area that is the industrial green chemistry of today. A few academic lecturers were also invited to share their knowledge of solvent-free chemistry and applying green chemistry to DFT calculations.

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Symposium participants learn about each other’s research during the poster session.

The final lecture, compiled by the GCI and presented by yours truly, was entitled “Preparing for the Future: Advice from Industry”. This lecture presented the responses from our invited speakers to a few questions we asked them, based on the necessary skill sets and experience required to push forward your resume when applying for an industry-based job, as well as their view of working in an industrial lab vs an academic setting. In the end, the best advice was to educate yourself broadly in science and in business, be active with extracurriculars during your studies, and most importantly to develop communication and people skills!

Highlights from the symposium included poster presentations featuring 14 posters (three of which won a monetary prize in a poster competition), dinner with the speakers in small groups, and a social event held at Harvest Kitchen with hors-d’oeuvres and drinks.

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Group picture taken during the social night!

Of course, we’d like to thank our sponsors for their funding to make this event possible: UofT Environmental Resource Network (UTERN), the UofT Chemistry department, GreenCentre Canada, UTGSU, and Ulife. Special thanks goes to Universal Promotions, who were very helpful in the process of making GCI notebooks for our symposium swag.

If you’d like to see more details including a full schedule of our 2015 Symposium, click here. ACCN also published an article featuring our event, please check it out here!

We’re already planning the theme and speakers for our 2016 Symposium, so stay tuned through our social media accounts for more announcements.

Thanks for stopping by and have a great day!