Advancing Green Chromatography: Sustainable Separation Strategies for Industrial and Agricultural Applications

Green chemistry is an approach to chemical design and manufacturing that seeks to minimize environmental impact and enhance sustainability by reducing or eliminating the use and generation of hazardous substances. Grounded in principles such as waste prevention, energy efficiency, the use of renewable feedstocks, and safer solvents and reaction conditions, green chemistry promotes processes that are both environmentally benign and economically viable. Its importance has grown significantly in response to increasing concerns over pollution, resource depletion, and the long-term effects of chemical exposure on human health and ecosystems. By integrating green chemistry principles into research, industry, and policy, scientists and engineers can develop innovative solutions that not only improve process efficiency and product safety but also contribute to a more sustainable and responsible future.

Mary Ellen McNally, the first female FMC Fellow at the Stine Research Center for FMC Corporation, has been widely recognized for her contributions to the field of separations including gas (GC), liquid (LC), and supercritical fluid chromatography (SFC), and for applications to help solve industrial and agricultural problems. Recently, LCGC International was able to interview her about her work and continued interests in green and sustainable chromatographic approaches and sample preparation.

What are the major hurdles encountered in applying green separation technologies in the agricultural industry, or industry in general?

Greener separations support product safety, regulatory compliance, and environmental stewardship all at once. In agricultural product development, as in pharmaceutical product development, comprehensive characterization of all components —typically down to low weight‑percent levels such as 0.1% by weight—is required to achieve registration. This requires reliable separation to identify, detect and quantitate the compounds that are present in an active ingredient.

Ideally, these identifying and quantifying processes are conducted with the best green technology possible.

To achieve the greatest impact greener solvents are what should be employed in enforcement methods. These are the methods that end up in the quality control laboratories at the manufacturing and formulation sites. They are run routinely, on every product batch, for the life of the product.

The major hurdle of choosing the most environmentally friendly solvent is mind set and cost.Most active ingredient manufacturers willingly put in place new technologies, for example, those that are greener, in a new product introduction. So, it behooves us to encourage the method development chemist to think green when a method is being developed.

The cost of changing technology for an older product is much more difficult. It is not just a change in sample prep and chromatographic conditions that needs to take place. Equivalency must be proven and approval must be gained from regulatory agencies—this is a major undertaking. Our databases contain thousands of methods, so this is a huge undertaking.

Why is it important to align laboratory separation techniques to improve overall sustainability in industrial product development?

The desirable goals to achieve a sustainable analysis process are approaches such as supercritical fluid chromatography, low organic solvent liquid chromatography, smaller column dimensions and solvent‑minimizing sample preparation.These goals align with reductions in hazardous solvent use, energy consumption, and waste generation and improve overall sustainability in industrial product development, both in the agricultural and pharmaceutical industries, as well as other regulated industrial product development.

Undoubtably, sample preparation remains the dominant contributor to environmental impact in the analytical laboratory. Yet, it often receives less attention from a green perspective than chromatography. A few needed developments include robust stationary phases compatible with greener mobile phases in chromatography and for sample preparation improvements a broader use of real‑time monitoring where no sample preparation is required.

How are green practices incorporated into chromatographic separations, is it important in method quality, compliance?

As an analytical community, I believe we are in our infancy in terms of incorporating greener methods. Most major corporations have sustainability goals, typically, a reduced emission percentage by a certain date. As an analytical/chromatographic, community, we are still in the process of developing and evaluating methods to determine a score for greenness. This is a need before we even start to adapt our methods to be greener—we need to be able to measure if the changes we make are greener.

We have some challenges ahead of us, balancing chromatographic selectivity with solvent reduction, scaling methods without compromising sustainability, and managing analytes that have low solution stability or span wide polarity ranges.Achieving a low or lower score from a green perspective is pointless if a problem is not solved.

Ultimately, as we achieve measurably more sustainable methods, the quality of the methods will be better this should be accomplished with no loss to the quality of the validation data we can achieve now with our current conventional solvents.

From a compliance perspective, we have seen requests for the use of greener, more environmentally friendly solvents. It is to a manufacturer’s advantage to start with the greenest solvent system possible, rather than go back and repeat method validations at the request of regulators.

Are there any benefits that are realized as green analytical methods are used more broadly? Can you define the scope of an analytical method?

The primary motivation and benefit is to achieve state-of-the-art analytical methods while reducing environmental impact for new products being introduced into the market. Upgrades to the methodology of old products, which were not developed with sustainability in mind, will be slower.

With the implementation of processes such as structured method‑selection frameworks, and early testing of solvent‑lean alternatives, along with tracking method performance improvements through sustainability metrics systems, zero impact goals can be achieved. This is important to note; the scope of analytical methods used in manufacturing is very broad. They are developed to monitor the products that are being made both inside the confines of the manufacturer’s business and outside via contract laboratories, contact research organizations (CROs), government laboratories, and compliance organizations.They are used to prove the quality of the material being made meets the registered specifications as well as to ensure that when a product is in the public domain, it is authentic and not counterfeit. Sustainable methods will have large long-term impact on achieving corporate, as well as government, green chemistry goals.