Investigation of Ion-Pairing Additives for the Supercritical Fluid Extraction of Triphenylphosphinetrisulfonate, Sodium Salt

• Published in: Journal of chromatographic science Vol. 36; no. 11; pp. 547 - 553
• Main Authors: Eckard, Phyllis R., Long, Gary L., Taylor, Larry T., Slack, Gregory C.
• Format: Journal Article
• Language: English
• Published: Niles, IL Oxford University Press 01.11.1998; Preston Publications
• Subjects: Analytical chemistry; Chemistry; Chromatographic methods and physical methods associated with chromatography; Exact sciences and technology; Other chromatographic methods; Phase composition; Ion pair; HPLC chromatography; Experimental study; Optimization; Operating conditions; Sodium Compounds; Organic anion; Chemical modification; Ultraviolet detector; Sample preparation; Ion extraction; Factorial design; Supercritical fluid extraction; Methanol
• ISSN: 0021-9665; 1945-239X
• DOI: 10.1093/chromsci/36.11.547

A screening study consisting of a fractional—factorial design is performed in order to identify the factors which contribute the most to the recovery of an anionic species, triphenylphosphinetrisulfonate (TPPTS), from a spiked-sand surface employing supercritical fluid extraction with carbon dioxide. The investigated experimental parameters are the type of ion-pairing additive (i.e., tetralkylammonium hydrogen sulfates) and its concentration, CO2 density, extraction temperature, static extraction time, CO2 mass used, liquid CO2 flow rate, and the volume of methanol spiked into the matrix prior to extraction. Of the eight factors investigated, four factors are identified as significantly affecting the recovery of the anionic species: ion-pairing reagent added to the spiked sand surface, ion-pairing reagent concentration, static extraction time, and volume of methanol present in the extraction vessel. The experimental parameters and settings identified as influential by the statistical approach are later shown in concert to yield 100% recovery of TPPTS from the spiked sand.