Flexible SFE / SFR system for small-scale pilot processing

The SFT-250 Supercritical Fluid Extraction / Reaction (SFE/SFR) Processing System from Activotec is designed to perform extractions and run reactions in a range of supercritical fluid media. This new high performance system was engineered to meet the day-to-day rigours of the research laboratory and provide the versatility for small-scale pilot processing.

The SFT-250 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 operational flexibility and safety features unmatched by any other laboratory SFE/SFR instrument available in the market today.

At the heart of the SFT-250 is a stainless steel vessel capable of containing supercritical fluids at pressures up to 10,000 psi. (68.9 mPa). The SFT-250 accommodates pressure vessels of up to 4 litres in size. This 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 SFE equipment. Additionally, the SFT-250 may be configured with multiple vessels, which may be operated simultaneously, either in series or in parallel. Vessels are easily interchangeable and may be installed readily by the user.

The SFT-250 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 SFT-250 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-pressurisation 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 SFT-250 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 SFT-250 to other instrumentation such as an FTIR or Mass Spectrometer. Additional collection options are available. The standard set-up is for collection into EPA vials.

PID controllers control the SFT-250. These manage pumping rates, pressures, temperature zones, mixing, and safety interlocks.