What is “extraction”?

Extraction is a process where one or more components are selectively separated from a liquid or solid mass or feedstock by an immiscible ’solvent’ (incapable of mixing). The extract is then recovered from the liquid at a later stage.

What is a Super Critical Fluid?

A supercritical fluid (SCF) can be defined as a substance above its critical temperature and pressure. The critical point represents the highest temperature and pressure at which the substance in question can exist as a vapour and liquid in equilibrium. The normal conditions for supercritical CO2 are above a ‘critical’ temperature of 31C and a ‘critical’ pressure of 74 bar. When sub critical the CO2 is in a liquid form and when it goes super critical it takes on the appearance of a dense ‘fog’.

How does it work?

In most cases extraction is essentially a diffusion-based system. (I.e. the CO2 is required to diffuse and permeate the raw material enabling the targeted extract to subsequently diffuse from the matrix and into the CO2.) The fluid is pumped to a heating zone, where it is heated to supercritical conditions. It then passes into the extraction vessel, where it rapidly diffuses into the solid matrix and dissolves the material to be extracted. The dissolved material is swept from the extraction cell into a separator at lower pressure, and the extracted material settles out. The CO2 can then be cooled, re-compressed and recycled.

What are the advantages of CO2 SCFE?

CO2 SCFE is widely regarded as the optimum extraction method for many reasons. It can attain higher yields owing to the greater penetration of the product. It is eco friendly and fully recyclable. Hazardous and toxic wastes are eliminated and therefore extracts are free of contaminants. Compounds can be selectively separated by manipulating pressure and temperature. Lower operating costs and greater stability and quality are achieved owing to the mild temperatures required in the process.

Why is everyone not using CO2 SCFE?

There are a few reasons for this. The capital costs of commercial scale CO2 SCFE equipment are prohibitively expensive. It is also a very niche industry and requires a specific expertise. The equipment operates at very high pressure and requires sensitive handling. The technology is often a long way from the core competency or skillbase of the prospective client.

Why is CO2E offering this service now?

The market for naturally sourced ingredients and products is growing at an unprecedented rate. What is more this is a consumer led phenomenon. There is a greater awareness of the properties of botanicals and a preference for natural compounds over synthetic solutions. Nutraceuticals, Flavour and Fragrances have been around for a long time but Cosmeceuticals is a relatively new and burgeoning industry.

How can CO2E help me?

At the time of writing, CO2E is the only company in the UK with the capacity to make widely available both R&D and commercial CO2 SCFE extraction in-house. This is a major advantage for many potential clients.

For growers seeking to diversify their revenue streams, CO2E is able to prove concept, optimise the extraction method and refine to a commercial standard – all under one roof. When the grower is then happy to commit more acres to a target crop, we have the capacity to extract on a commercial scale.

For ingredient suppliers, fragrance houses and formulators we have the laboratory capacity and expertise to investigate new compounds, botanicals and applications. We can work with clients to optimise existing processes, source new compounds and develop new products.

Contact the CO2E team today to find out how we can help.