Supercritical fluid extraction processing shows numerous advantages when compared to traditional organic solvent extraction. In traditional extraction, for example, the residual solvent is unavoidable. In supercritical fluid extraction, however, there is no residual solvent in the final product. This translates into lower operating costs because of the reduction in post–processing steps, clean–up and safety measurements. Additionally, because CO2 processing requires low temperatures, there is less deterioration of heat sensitive components in the extract. Furthermore, since there is no oxygen in the process, the potential for oxidation of the extract is significantly minimized.

Thar Instruments is a designer, developer, and manufacturer of solvent–free pilot ⁄ lab–scale supercritical fluid extraction systems. The laboratory supercritical fluid extraction (SFE) system scale models start from 100 mL up to 10 L. Models can include co–solvent pump, fractionation and recycling.

SFE applications in the food and pharmaceutical industries:

• Decaffeinating of coffee and tea

• Extraction of essential oils (vegetable and fish oils)

• Extraction of flavors from natural resources (nutraceuticals)

• Extraction of ingredients from spices and red peppers

• Extraction of fat from food products

• Fractionation of polymeric materials

• Extraction from natural products

• Photo–resist cleaning

• Precision part cleaning

Supercritical Anti Solvents: SAS

Supercritical fluid reaction is a reaction process using a supercritical fluid as a solvent. When a fluid is taken above a particular temperature and pressure (critical point of the respective fluid), it exists in a condition called the supercritical fluid state. The physio–chemical properties of a fluid in the supercritical state are in between those of a typical gas and liquid. For example, the density of a supercritical fluid can be changed by varying the pressure on the fluid. As a result, a supercritical fluid can have a density that ranges between those exhibited by gases to liquid–like values when the fluid is compressed at high pressures. Carbon dioxide is certainly the most popular fluid because of its physiological compatibility, non–toxicity, inflammability, easy availability, convenient critical parameters (Tc= 31° Celsius, Pc=7.38 MPa), inexpensiveness and environmental friendliness.

The Supercritical Fluid Reaction (SFR) systems are built to enable the user to rapidly react multiple compounds with supercritical CO2, and extract materials of interest. The user can operate in a static, pressure control mode or a dynamic flow control mode. Thar produces off–the–shelf, automated SFR⁄ Supercritical Fluid Extraction (SFE) kits for use in pharmaceutical, chemical and food research laboratories.

Supercritical Fluid Reaction Systems applications:

• Chemical reactions

• Polymerization

• Catalysis

• Oxidations

• Hydrogenations

Thar Instruments´ Supercritical Phase Monitor is an important tool for observing phase behavior and solubility of materials under pressure, temperature, and sample concentration conditions. The equipment features a variable volume viewcell body with a piston. The high pressure motor–driven mixer allows the user to achieve high stirring rates in the viewcell. The CCD camera and illumination source, with two sapphire windows mounted 90° apart in the body, provide the capability to view inside the viewcell. For temperature control, the viewcell body is uniformly heated using embedded heaters. Additionally, a simple lever–operated mechanism and a precision valve enable the user to increase and decrease the pressure, respectively, in the viewcell. A unique stand assembly allows viewcell rotation up to 180° that allows inversion and viewing of different phases (if present).

SPM20 Applications:

• Material solubility

• Solvents and CO2 phase behavior

• Solubility studies for particle design

• Polymer swelling under pressure

• Chromatography optimization

• Reaction conditions

• Crystalization of compounds