How Green is the Future of Chromatography?

As the world becomes ever more conscious of environmental sustainability, science continues to evolve to meet the growing demand for greener practices. With its widespread application in pharmaceuticals, environmental monitoring, food safety, and forensics, chromatography has a role to play in reducing the environmental footprint of the laboratory.

Close-up of a molecular structure amid lush green foliage, symbolizing the intersection of nature and science in sunlight © Chanwit - stock.adobe.com

The three primary objectives of green chromatography are: i) reduce or eliminate hazardous solvents; ii) decrease energy consumption; and iii) minimize waste generation.

Traditional chromatography techniques, particularly high performance liquid chromatography (HPLC), rely heavily on organic solvents such as acetonitrile and methanol. These solvents contribute to environmental pollution, are costly to dispose of, and pose health hazards to laboratory personnel (1). As a result, researchers are increasingly focusing on developing solvent-free techniques.

Supercritical fluid chromatography (SFC) is considered a green analytical technique because it utilizes carbon dioxide (CO2) as the primary mobile phase instead of organic solvents. Supercritical CO₂ is non-toxic, has low viscosity and high diffusivity, allowing for faster separations and reduced solvent waste.As the world becomes ever more conscious of environmental sustainability, science continues to evolve to meet the growing demand for greener practices. With its widespread application in pharmaceuticals, environmental monitoring, food safety, and forensics, chromatography has a role to play in reducing the environmental footprint of the laboratory.

The three primary objectives of green chromatography are: i) reduce or eliminate hazardous solvents; ii) decrease energy consumption; and iii) minimize waste generation.

Traditional chromatography techniques, particularly high performance liquid chromatography (HPLC), rely heavily on organic solvents such as acetonitrile and methanol. These solvents contribute to environmental pollution, are costly to dispose of, and pose health hazards to laboratory personnel (1). As a result, researchers are increasingly focusing on developing solvent-free techniques.

Supercritical fluid chromatography (SFC) is considered a green analytical technique because it utilizes carbon dioxide (CO2) as the primary mobile phase instead of organic solvents. Supercritical CO₂ is non-toxic, has low viscosity and high diffusivity, allowing for faster separations and reduced solvent waste.

Another approach is ultrahigh-pressure liquid chromatography (UHPLC), which uses smaller particle sizes and higher pressures to achieve greater efficiency (1). UHPLC systems require significantly less solvent than conventional HPLC, making them a greener alternative while maintaining high sensitivity and resolution.

In gas chromatography (GC), nitrogen gas may be a suitable carrier gas–dependent on application. Hydrogen offers swifter separations than nitrogen or helium but does require the purchase of high-pressure cylinders or a hydrogen generator (2); offsetting the costs is something to look at on a lab-by-lab basis.

Column materials are another aspect of separation science that can be made Greener. Traditionally, chromatographic stationary phases are composed of silica or polymer-based materials that require intensive chemical processing. For example, researchers have explored the use of cellulose-based materials in liquid chromatography (3) because of their renewable origin and more sustainable disposal options. In addition, metal-organic frameworks (MOFs) show promise in separation science due to their high porosity, tunable selectivity, and potential for recyclability (4).

The miniaturization of chromatography instruments is another exciting trend in green analytical chemistry. Microfluidic chromatography systems, or lab-on-a-chip technologies, allow for ultra-low sample and solvent volumes, significantly reducing chemical waste. These systems are particularly useful for environmental monitoring, biomedical diagnostics, and pharmaceutical testing, where rapid, on-site analysis is crucial.

Beyond reducing solvent consumption, green chromatography aims to improve energy efficiency. One way this is being achieved is by optimizing methods for lower temperatures. Reducing the need for high-temperature operation in GC, for instance, leads to lower energy consumption and a reduced carbon footprint.

Another approach is the integration of automated and smart chromatography systems that optimize separation conditions in real time, reducing analysis time and energy use. Manufacturers are increasingly producing instruments with green credentials in mind. Artificial intelligence (AI) and machine learning algorithms are also being employed to predict optimal chromatographic conditions, minimizing trial-and-error experiments that generate unnecessary waste.

The push toward green chromatography is not solely driven by academic research—it is also a priority for regulatory agencies and industry leaders. The United States Environmental Protection Agency (EPA) and the European Chemicals Agency (ECHA) are enforcing stricter guidelines on solvent disposal and hazardous chemical use, incentivizing laboratories to adopt greener practices.

Just a quick search of the internet suggests that we will continue to see the following trends:

• Increased adoption of eco-friendly mobile phases, such as ionic liquids and water-based solvents
• Advancements in solvent recovery and recycling technologies to further minimize waste
• Further implementation of AI-driven chromatography optimization to reduce unnecessary experiments and energy use
• Development of biodegradable and renewable stationary phases to lessen reliance on traditional silica-based materials.

Green analytical chemistry is no longer a niche concept but a necessity in today’s environmentally conscious world. Through solvent reduction, alternative materials, miniaturization, and energy efficiency, the future of chromatography is hopefully poised to be greener than ever.

Tell me what you think. Is there more that can be done? For example, is there an initiative to recycle columns in your area? Please continue the conversation in the comments below.

References

(1) Bell, D. S. The Role of HPLC Columns in Shaping a Greener Analytical Future. LCGC Intern. 2025, 2(1), 1417. DOI: 10.56530/lcgc.int.qs4378z2

(2) Snow, N. H. Green Chemistry: What Is It (and What Is It Not)? And How Does It Apply to Gas Chromatography? LCGC N. Am. 2023, 41(5), 176–180. DOI: 10.56530/lcgc.na.az3979e4

(3) Yao, T.; Song, J.; Hong, Y.; et al. Application of Cellulose to Chromatographic Media: Cellulose Dissolution, and Media Fabrication and Derivatization. J. Chrom A. 2023, 1705, 464202. DOI: 10.1016/j.chroma.2023.464202

(4) Gutiérrez-Serpa, A.; Pacheco-Fernández, I.; Pasán, J.; Pino, V. Metal–Organic Frameworks as Key Materials for Solid-Phase Microextraction Devices—A Review. Separations 2019, 6(4), 47. DOI: 10.3390/separations6040047