Publication Date: 2014-Mar-11
The IP.com Prior Art Database
phase separating nozzle as pressure maintenance member for supercritical fluid chromatography apparatus
 The present description relates to a phase separating nozzle which may be for instance used and implemented in supercritical fluid chromatography – SFC – as disclosed for example in US 4,982,597.
 In a sample separation device based on the principle of liquid chromatography, a fluidic sample to be separated is injected in a mobile phase (such as a solvent composition), wherein the mixture may be pumped through conduits and a separation column comprising a material (stationary phase) which is capable of separating different components of the fluidic sample. Such a material, so-called beads which may comprise silica, may be filled into a column tube which may be connected to other elements (like a sampling unit, a flow cell, containers including sample and/or buffers) by conduits.
 Supercritical fluid chromatography (SFC) is a form of normal phase chromatography that is used, inter alia, for the analysis and purification of low to moderate molecular weight molecules. Principles of SFC are similar to those of high performance liquid chromatography (HPLC). However, SFC typically utilizes dense, high pressure carbon dioxide - CO2 - (or any other [supercritical] fluids) as a component of the mobile phase. To keep the carbon dioxide component of the mobile phase miscible with organic solvents as a secondary component of the mobile phase, the entire chromatographic flow path has to be pressurized. SFC has the particular advantage that carbon dioxide has a low viscosity and a high diffusion coefficient so that a rapid chromatographic separation is rendered possible. At the same time, no or very low expenses for the disposal of waste occurs when using SFC in particular with carbon dioxide.
 Numerous instances of gas liquid separation and liquid collection exist utilizing cyclones, valves, and vessels. One specific implementation is disclosed in US 6,632,353. In US 6,632,353, large capacity heaters, tubing, restrictions, and back pressure regulators are serially disposed in the flow stream after any chromatographic back pressure regulation. In this position, the flow stream is moving rapidly, and the expanded CO2 behaves as a thermal insulator. Thus, high wattage heating and increased residence time is required. Additionally, redundant heating is required to minimize or reduce aerosol formation prior to any collection stage.
summary of the technical innovation
 According to the innovation disclosed herein, a further developed phase separating nozzle for a supercritical fluid chromatography apparatus is explained. By utilizing heating prior to the decompression and expansive cooling of supercritical fluid within the nozzle, the capacity and location of the heaters will change. A coalescence frit or filter immediately downstream of the nozzle’s decompressive region mitigates the f...