Supercritical Fluid Extractor

What is the Supercritical Fluid Extractor?

A supercritical fluid extractor uses carbon dioxide above its critical point to extract analytes efficiently with little or no organic solvent. It is used for food, natural product and polymer applications in the laboratory.

Overview

A supercritical fluid extractor pumps carbon dioxide above its critical temperature and pressure, where it behaves as a dense fluid with gas-like viscosity and diffusivity. This penetrates the sample matrix rapidly and dissolves non-polar and moderately polar analytes, and a co-solvent such as ethanol or methanol extends the range to more polar compounds. After extraction, reducing the pressure converts the carbon dioxide back to gas, leaving a solvent-free extract and allowing the gas to be recycled. The technique is fast, uses little or no organic solvent and is gentle on labile compounds, and it is used for decaffeination, essential oils, flavours and polymer additives.

How does it work?

Extraction transfers analytes from a solid or semi-solid matrix into a solvent that can be analyzed or further cleaned. Soxhlet extraction repeatedly cycles condensed solvent through the sample, giving thorough extraction over time. Accelerated solvent extraction uses elevated temperature and pressure to keep the solvent liquid and speed transfer. Supercritical fluid extraction uses carbon dioxide above its critical point, whose low viscosity and high diffusivity penetrate the matrix rapidly and leave little residue. Microwave extraction heats the solvent and sample together, while ultrasonic extraction uses cavitation to disrupt the matrix and improve mass transfer. Temperature, pressure, solvent choice and time determine recovery.

What are the key features?

• Supercritical carbon dioxide as the extraction fluid
• Co-solvent option for polar analytes
• Solvent-free extract after depressurisation
• Carbon dioxide recycling to reduce consumption
• Low temperature for labile compounds

What are the technical specifications?

A typical supercritical fluid extractor configuration offers extraction pressure of 10–50 MPa, extraction temperature of 35–80 °C, extraction vessel volume of 5–1,000 mL, carbon dioxide flow of 1–20 L/h, co-solvent of Ethanol or methanol, 0–20% and extraction time of 15–120 min. Values are indicative of the product class; the exact figures for each configuration are confirmed on the quotation and the calibration documents supplied with the instrument.

Which applications is it used for?

The Supercritical Fluid Extractor is used in essential oil and flavour extraction, decaffeination and natural product isolation, polymer and plasticiser extraction and food contaminant and lipid analysis. Across the wider Extractors class, laboratories also deploy it for fat and oil determination in food, environmental organic pollutant extraction and pharmaceutical and natural product isolation.

Which standards and certifications apply?

Relevant standards and methods include EPA 3540C, EPA 3545A, EPA 3546, ISO 659 and IEC 61010-1. Certification candidates for this model are CE and ISO 9001 manufacturing; each is to be confirmed for the specific configuration before shipment, and certificates are supplied only where they have been issued.

Handle solvents in a fume hood and use the protective equipment specified for the solvent and the extraction conditions. Dry and grind the sample consistently, because moisture and particle size affect penetration and recovery. Optimise and validate temperature, pressure, solvent and time for each matrix, and verify recovery with a certified reference material or a spiked sample. Clean and check seals, vessels and tubing, since leaks waste solvent and can be hazardous at high pressure. Recover or dispose of solvents according to regulations, and record all parameters for traceability.

How do I select the right Supercritical Fluid Extractor?

Choose a supercritical fluid extractor for efficient, solvent-free extraction of non-polar and moderately polar analytes, or for heat-sensitive natural products. Confirm the pressure and temperature range, whether a co-solvent is needed, and the vessel size for the sample mass. In an RFQ state the analyte polarity, sample type, batch size and whether solvent-free extract is required.

How does it compare with other Extractors variants?

Choose an extraction technique according to the analyte, the matrix and the required throughput. Soxhlet extraction is the classical reference method and suits fat and oil determination, but it is slow and uses more solvent. Accelerated solvent extraction is faster and uses less solvent, and suits many environmental and food methods. Supercritical fluid extraction is efficient and nearly solvent-free, and suits non-polar and moderately polar analytes. Microwave and ultrasonic extraction are rapid and suit samples where the matrix is easily penetrated. Confirm the achievable recovery, the solvent consumption, the temperature and pressure limits, and whether the system can handle the sample number required.