Abstract: To provide performance particularly in handling supercritical extraction systems, a specially designed pump includes a cam-driven, single-plunger with a cam having a profile that enables the pumping system to avoid destructive reverse torque on the cam, gear train and drive motor after the cam passes top dead center. The plunger includes a seal having one side in contact with the supercritical fluid and a mechanism for supporting and aligning the piston on the other side of the seal to maintain the piston in alignment. The piston drive has Hertzian contact with the piston. The fluid volume leaving the pump is determined by measuring only pressure or other parameters related to flow and movement of the plunger. Measurement of the fluid volume leaving the pump is useful for recording or indicating the flow rate while the pump is operating.

Abstract: A variable-orifice fluid restrictor for use with a supercritical extractor or chromatograph includes an inlet line for fluid at a pressure above its critical pressure, an extended tubular probe having an inner and an outer surface and a proximal and a distal end. The proximal end of the probe is disposed toward the inlet line. The distal end of the probe includes an adjustable orifice means adapted for metering the fluid and having first and second orifice members and an adjusting stem having first and second ends. The adjustable orifice means is adjacent to the outer surface of the probe and the orifice means is adjustable with the adjusting stem. The end of the adjusting stem is located at the distal end of the probe and is adapted for moving the first orifice member with respect to the second orifice member to control the adjustable orifice for varying the restriction of fluid passing through the adjustable orifice.

Abstract: An apparatus for supercritical extraction is disclosed herein. The apparatus includes a plurality of containers adapted to hold a different one of a corresponding plurality of samples, a first transport means for carrying the plurality of sample containers, and a second transport means for transporting a selected container from the first transport means to a supercritical extractor. The supercritical extractor includes a heating means having a recess for receiving the selected container, means for passing fluid at a supercritical condition through the selected container, and a receiving means for receiving extractant from the selected container. A programming means is provided to control the first and second transport means.

Abstract: To collect analyte from a supercritical fluid extractor, the collector lifts vials into place by a biasing means that guides the file up to the restrictor where it is sealed. The vial can be moved back down from the collecting mechanism even if frost forms on the vial while the restrictor means remains stationary. This vial is held in place by a guide that contains the seal for sealing the vial when it is raised in place.

Abstract: A variable-orifice fluid restrictor for use with a supercritical extractor or chromatograph includes an inlet line for fluid at a pressure above its critical pressure, an extended tubular probe having an inner and an outer surface and a proximal and a distal end. The proximal end of the probe is disposed toward the inlet line. The distal end of the probe includes an adjustable orifice means adapted for metering the fluid and having first and second orifice members and an adjusting stem having first and second ends. The adjustable orifice means is adjacent to the outer surface of the probe and the orifice means is adjustable with the adjusting stem. The end of the adjusting stem is located at the distal end of the probe and is adapted for moving the first orifice member with respect to the second orifice member to control the adjustable orifice for varying the restriction of fluid passing through the adjustable orifice.

Abstract: An automatic variable-orifice fluid restrictor for use with a supercritical extractor having a collection trap or a supercritical chromatograph includes an inlet line for fluid at a pressure above its critical pressure, an extended tubular probe having an inner and an outer surface and a proximal and a distal end. The proximal end of the probe carries an inlet connected to the inlet line and is outside of the trap. The distal end of the probe includes a variable orifice means adapted for metering the fluid. The variable orifice means is adjacent to the outer surface of the probe and is located in the midst of the trap. The variable orifice means is adjusted by an adjusting stem having first and second ends. The first end of the adjusting stem is connected to automatic control means such as a servo at the proximal end of the probe and outside of the trap. The second end of the adjusting stem varies the area of the orifice by moving a first orifice member.

Abstract: To avoid deposits on the restrictor that channels extractant into a collector, a heated capillary tube pressure release restrictor, has a thermally insulated outlet end in a collecting trap substantially colder than the capillary tube. The restrictor is heated between the insulation and the capillary tube by Joulean heating. The solvent in the trap is at a pressure of 5 to 200 psi above atmospheric pressure. The thermal resistance of the insulation is selected to reduce the heat added to the extractant to a minimum and yet cause the temperature of the extractant to be in a range within which it is sufficiently hot so it does not freeze when added to the collection solvent but not so hot as to reduce partitioning of the extract and extractant before the extractant leaves the collection solvent. It has a thermal conductivity no greater than 60 BTU's per hour, per square foot, per inch for a one degree Fahrenheit difference.

Abstract: To provide performance particularly in handling supercritical extraction systems, a specially designed pump includes a cam-driven, single-plunger with a cam having a profile that enables the pumping system to avoid destructive reverse torque on the cam, gear train and drive motor after the cam passes top dead center. The fluid volume leaving the pump is determined by measuring only pressure or other parameters related to flow and movement of the plunger. Measurement of the fluid volume leaving the pump is useful for recording or indicating the flow rate while the pump is operating.

Abstract: To collect analyte from a supercritical fluid extractor, the collector lifts vials into place by a biasing device that guides the file up to the restrictor where it is sealed. The vial can be moved back down from the collecting mechanism even if frost forms on the vial while the restrictor remains stationary. This vial is held in place by a guide that contains the seal for sealing the vial when it is raised in place.

Abstract: In a piston pump for pumping liquid carbon dioxide at a temperature below 30 degrees Fahrenheit and pressures at least as high as 7500 psi, the volume leaving the pump is determined by measuring only pressure or other parameter related to flow and movement of the plunger. The position of the piston is measured and the resulting displacement is integrated to determine volume of fluid pumped.

Abstract: A variable-orifice fluid restrictor for use with a supercritical extractor or chromatograph includes an inlet line for fluid at a pressure above its critical pressure, an extended tubular probe having an inner and an outer surface and a proximal and a distal end. The proximal end of the probe is disposed toward the inlet line. The distal end of the probe includes an adjustable orifice means adapted for metering the fluid and having first and second orifice members and an adjusting stem having first and second ends. The adjustable orifice means is adjacent to the outer surface of the probe and the orifice means is adjustable with the adjusting stem. The end of the adjusting stem is located at the distal end of the probe and is adapted for moving the first orifice member with respect to the second orifice member to control the adjustable orifice for varying the restriction of fluid passing through the adjustable orifice.

Abstract: In a piston pump for pumping liquid carbon dioxide at a temperature below 30 degrees Fahrenheit and pressures at least as high as 7500 psi at an outlet flow rate in excess of 10 milliliters per minute, the inlet to the pump and the pumphead are each cooled by thermoelectric heat exchangers that are air cooled. The pump is a cam-driven, single-plunger pump with a cam profile that enables the pumping system to avoid distructive reverse torque on the cam, gear train and drive motor after the cam passes top dead center. The volume leaving the pump is determined by measuring only pressure or other parameter related to flow and movement of the plunger. The piston of the pump is supported on both sides of the seal and the support for the piston within the pumphead are machined consentrically and colinearly to the seal gland.

Abstract: To supply supercritical fluid to an automatic supercritical fluid extractor and collect extract from the extractor, sample holding cartridges are lifted one by one in series by an elevator plug into a pressure chamber. An inlet at the top of the cartridge engages a pressure vessel inlet for the extractant so that extractant flows into the cartridge and into the space between the cartridge and inner walls of the pressure chamber. The outlets from the cartridge and pressure vessel communicate with the collector and exhaust through passageways in the plug. The plug has cleaning ports for cleaning seals and the outlet from the cartridge flows past the seals. The collector lifts vials into place and can precool the collection solvent, and later as part of the collection procedure, heat and pressurize the collector.

Abstract: To avoid deposits on the restrictor that channels extractant into a collector, a heated capillary tube pressure release restrictor, has a thermally insulated outlet end in a collecting trap substantially colder than the capillary tube. The restrictor is heated between the insulation and the capillary tube by Joulean heating. The solvent in the trap is at a pressure of 5 to 200 psi above atmospheric pressure. The thermal resistance of the insulation is selected to reduce the heat added to the extractant to a minimum and yet cause the temperature of the extractant to be in a range within which it is sufficiently hot so it does not freeze when added to the collection solvent but not so hot as to reduce partitioning of the extract and extractant before the extractant leaves the collection solvent. It has a thermal conductivity no greater than 60 BTU's per hour, per square foot, per inch for a one degree Fahrenheit difference.