摘要:
A system for chilling a pumping system includes a Peltier cooling element, and first and second heat exchangers. The Peltier element is arranged near a pump head of a pump such that the Peltier element and the pump head are in thermal contact, where the Peltier element chills the pump head and a mobile phase flowstream prior to fluid from the mobile phase flowstream entering the pump. The first heat exchanger is attached to the Peltier element, and removes heat from the Peltier element using a circulating fluid. The second heat exchanger cools the circulating fluid, where the Peltier element and the pump head are arranged in an area that is isolated from the second heat exchanger.
摘要:
Methods and systems for pumping compressible fluids in high pressure applications such as high-pressure liquid chromatography (HPLC) or supercritical fluid chromatography (SFC) applications are disclosed. An improved cooling device for a pump head for use in a supercritical fluid chromatography (SFC) system is described. A system for chilling a pumping system, includes a Peltier cooling element in thermal contact with a pump head, wherein the cooling element chills the pump head and a mobile phase fluid flowstream prior to the mobile phase fluid entering the pump; a fluid-cooled heat exchanger, attached to the Peltier cooling element, which removes heat from the cooling element using a circulating fluid; and a second heat exchanger which cools the circulating fluid.
摘要:
A fractionated sample collection process and device having at least one pressurized chamber used to gather and store liquid samples generated from a flow stream containing a mixture of highly compressed gas, compressible liquid, or supercritical fluid and a relatively incompressible liquid. A bank of multiple collection chambers is secured together in a frame to form a cassette unit. Each collection chamber may house a replaceable liner such as a test tube vial, to hold a fractionated liquid phase sample. After filling with sample, a collection chamber is returned to a clean state and ready for refilling with a new sample by manually or automatically replacing the liner.
摘要:
In a system for analyzing a chemical sample by chromatographic separation of said sample into components a method and apparatus are provided for heating the mobile phase to a desired temperature prior to exiting the restrictor, while maintaining the density of the mobile phase at a desired level. Such heating and density maintenance being provided by the combination of a restrictor having a minimal taper length and a temperature zone immediately prior to the outlet end of the restrictor, which temperature zone has a minimum length. A second temperature zone spaced upstream from the first zone, and an intermediate thermally conductive member between the first and second zones can be provided as an alternative embodiment for establishing a thermal gradient. As the mobile phase passes through the second zone, the intermediate conductive member, and the first zone, the mobile phase is subjected to a thermal gradient.
摘要:
In a system for analyzing a chemical sample by chromatographic separation of said sample into components a method and apparatus are provided for maximizing detector resolution and minimizing duration by maintaining the linear velocity of the mobile phase at a desired level by affecting the viscosity and density characteristics of the mobile phase as it passes through a restrictor by programming the restrictor temperature.
摘要:
An apparatus, system, and process of converting a standard, high performance liquid chromatography (HPLC) flow path to a flow path suitable for supercritical fluid chromatography (SFC) are described. This reversible technique is applied to a variety of flow configurations including binary, high pressure solvent mixing systems and quaternary, low pressure solvent mixing systems than can be conventionally operated or automated. The technique is generally applied to the fields of supercritical fluid chromatography and high pressure liquid chromatography, but users skilled in the art will find utility for any flow system where pressurization components must be periodically applied to and removed from both ends of a flow stream in an automated manner.
摘要:
A fractionated sample collection process and device having at least one pressurized chamber used to gather and store liquid samples generated from a flow stream containing a mixture of highly compressed gas, compressible liquid, or supercritical fluid and a relatively incompressible liquid. A bank of multiple collection chambers is secured together in a frame to form a cassette unit. Each collection chamber may house a replaceable liner such as a test tube vial, to hold a fractionated liquid phase sample. After filling with sample, a collection chamber is returned to a clean state and ready for refilling with a new sample by manually or automatically replacing the liner.
摘要:
An improved method of introducing sample into a low-pressure flow stream of a high-pressure chromatography system to improve efficiency and significantly shorten the time of the separation process through a chromatography column is described. The method comprises injecting samples in a modifier liquid flow stream upstream of a mixing column that combines two independent flow streams of a liquid modifier with a highly compressed solvating fluid. Focusing can be controlled at the column head by changing the ratios of the two flow streams. Total flow may also be adjusted to speed the application of the sample onto the column during injection. The method improves the timing and efficiency of a supercritical fluid chromatography system and can reduce the amount of modifier added to the mobile phase flow stream.
摘要:
An efficient and safe method and apparatus for collecting exhaust gasses in an open-air sample collection container in a supercritical fluid chromatography system is claimed. The invention uses a vacuum force to evacuate the gaseous phase and vapors separated from liquid mobile phase in a sample collection device. The invention is portable to use on a series of collection containers, such as test tubes or wells in a titration place. Embodiments are claimed for capture of gasses and vapors either internally or externally to a collection container. The invention removes the gasses from the collection container that are then safely vented to a waste collector, thereby creating a safer environment for the laboratory and properly removing and disposing potentially hazardous chemicals instead of venting these chemicals into the environment.
摘要:
An improved method and apparatus for safely introducing sample into a flow stream of a supercritical fluid chromatography system is described. The sample injection method improves safety of injection by eliminating the risk of injecting sample into a high-pressure system containing liquids and gasses at or near supercritical ranges. The method improves the efficiency and significantly shortens the time of the injection process by using a check valve placed between a fill port on an injection valve and sample port where sample is injected by a syringe. After sample injection from a sample loop into a high-pressure flow stream, an injection valve is reset to receive a subsequent sample. High-pressure flow stream mixtures become trapped within the sample loop when the valve is reset. The check valve prevents the mixtures from expanding into the sample port and blowing out a syringe and flow stream mixtures from the fill lines. The trapped flow stream mixtures are directed to a waste port where they are safely contained. The technique can be applied equally as effective to preparatory SFC as well as to analytical SFC systems.