THE SFT-250 SFE System

Leadership Features:

• Capacity up to 5 Liters
• Pressures up to 10,000 psi (68.9 MPa)
• Feedback Control: PID-Fuzzy Logic Controllers
• Various Extract Collection Options
• Optional Co-Solvent Addition Modules Fluid Preheater
• Easy to Upgrade System for New Applications
• Maintenance Free Operation

Click Here to download a printable version of the SFT 250 spec sheet in PDF format.

The SFT250 SFE Processing System is designed to perform extractions in a supercritical fluid media. This system was engineered to meet the day-to-day rigors of the research laboratory and may be used for small scale pilot processing. The SFT250 is simple to operate, easy to modify for evolving application needs, and features many of the performance characteristics of fully automated pilot scale systems. The SFT-250 offers the maximum flexibility and safety features of any laboratory supercritical fluid extraction instrument available in the market today.

At the heart of the SFT250 is a stainless steel vessel capable of containing supercritical fluids at pressures up to 10,000 psi. (68.9 MPa). The SFT250 accommodates pressure vessels of up to 5 liters in size. The large vessel enables the user to extract very low levels of key components from materials or process larger amounts of bulk material than would be possible with conventional, analytical scale SF equipment. Vessels are easily interchangeable and may be installed readily by the user.

The SFT250 incorporates a high performance, air driven pump which can rapidly produce the high pressures required for supercritical fluid work. Under typical operating conditions, flow rates range from 1 to 330 ml./min. (250 grams/min.) of liquid CO2. Conveniently located front panels allow easy access to the pressure vessel, valves, fittings, and electronics. Manually actuated valves provide long term, maintenance free performance.

Safety is of primary importance in all SFT250 systems. Electronic alarms alert the end user to potential over-temperature and over-pressure conditions. As an additional safety precaution, rupture disc assemblies provide mechanical protection against over-pressurization of the system.

A robust, variable restrictor valve (back pressure regulator) provides precise control over flow rates. This level of control is essential when it is necessary to achieve highly reproducible results from run to run. While carbon dioxide is the most commonly used solvent, the SFT250 allows the user flexibility to work with a variety of supercritical fluids. The extract collection options include solid phase extraction (SPE) cartridges, solvent filled vessels, EPA vials, and fractional cyclonic separators. Extract is collected outside the main cabinet, to provide ready access for the user and simplify interfacing the SFT250 to other instrumentation such as an FTIR or Mass Spectrometer. Additional collection options are available. The standard setup is for collection into EPA vials.

The SFT250 is controlled by PID controllers. These manage pumping rates, pressures, temperature zones, mixing, and safety interlocks.

System Specifications

Standard Configuration:
Maximum Operating Pressure: 10,000 psi. (68.9 MPa).
Pressure Display: LED. ± 1 psi. (6.9 kPa).

Temperature Range: 1Ambient to 200˚C.
Temperature Precision: ±0.5˚C.
Temperature Display: LEDs display internal and external vessel temperatures; restrictor and preheater temperatures.
Flow Rates: Up to 250 grams/min. (330 ml/min.)liquid CO2 under standard operating conditions.
Restrictor Valve:  User selectable, variable temperature control to 250˚C, resistant to blockage.
Extraction Vessel Size:  Up to 5 liter (bench scale). Vessels are user interchangeable.
Collection Vessel:  Externally mounted. Many options are available.
Heating Band Power:  All extraction vessels are heated with band heaters (4000 watts max.
Heating Power: All extraction/reaction vessels are heated with band heaters (2000 watts max.)
Over-Pressure Safeguards: Rupture disc assemblyand PID safety interlock.

Instrument Control: All temperature zones (vessel, restrictor, and preheater), pressures, and pressure ramps are controlled by PID-Fuzzy Logic Controllers.


Dimensions: Width: 61 cm, Depth: 61 cm, Height: 96 cm.
Weight (excluding vessel): 64 kg (140 Lb).

Configuration Options 
Interchangeable Sample Vessel: 100, 300, 500,1000, 2000, 4000, and 5000 ml (with 5 micron frits).Windows available.
Co- solvent Addition Module: Manual doping or direct, in-line metered addition.
Preheater: Improves temperature consistency of the fluid in large vessels by heating the fluid before it reaches the main pressure vessel. Recommended for all extraction systems.
Remote Control Software: Controls the SFT250 from a PC and performs data logging.

System Requirements
Power Requirements: 220 VAC., single phase,20 amps. (International power available).
Gas Supply: Liquid CO2 cylinder with dip tube.
House Air: Dry air, regulated to 110 psi.(760 kPa)