Tag Archives: extraction
Incorporating a Separation Into a Flow Injection Analysis
Dialysis and gaseous diffusion are accomplished by placing a semipermeable membrane between the carrier stream containing the sample and an acceptor stream. Shown here is a flow injection manifold incorporating a semipermeable membrane. The smaller green solutes can pass through the … Continue reading
Solid-State Extractions
Illustration showing four possible mechanisms for the solid-state extraction of an analyte: (a) adsorption onto a solid substrate; (b) absorption into a thin polymer film or chemical film coated on a solid substrate; (c) metal–ligand complexation in which the ligand … Continue reading
Purge-And-Trap Extraction
Schematic diagram of a purge-and-trap system for extracting volatile analytes. The purge gas releases the analytes, which subsequently collect in the primary adsorbent trap. The secondary adsorption trap is monitored for evidence of the analyte’s breakthrough. When the extraction is complete, … Continue reading
Soxhlet Extraction
In a Soxhlet extraction, the extracting solvent is placed in the lower reservoir and heated to its boiling point. Solvent in the vapor phase moves upwards through the tube on the far right side of the apparatus, reaching the condenser … Continue reading
Solid-Phase Extraction
In a solid-phase extraction of a liquid sample, we pass the sample through a cartridge containing a solid adsorbent. A typical separation is illustrated here. Before adding the sample, the solid phase cartridge is rinsed with suitable solution. Next, as shown … Continue reading
Liquid-Liquid Extraction
Illustration showing a liquid–liquid extraction using a separatory funnel: (a) before the extraction, 100% of the analyte is in phase 1; (b) after the extraction, most of the analyte is in phase 2, although some analyte remains in phase 1. … Continue reading