Extraction of small amounts of dialkylphosphorodithioates with tetraphenylarsonium

✍ Scribed by V. Drevenkar; Z. Fröbe; B. Štengl; Z. Štefanac

• Publisher: Elsevier Science
• Year: 1983
• Tongue: English
• Weight: 699 KB
• Volume: 154
• Category: Article
• ISSN: 0003-2670
• DOI: 10.1016/0003-2670(83)80028-2

✦ Synopsis

The extraction behaviour of Ion-pairs formed by dialkylphosphorodithioates with tetraphenylarsonium cation was examined for the dichloromethane-water system. The mole ratio method, with spectrophotometric and conductimetrrc measurements of the organic phase, showed the mole ratio of the ion-pair to be 1:l. Dissociation of the ionpairs occurred at concentrations in the aqueous phase lower than lO* mol dmW3 for the dimethyl compound and 6 X lo4 mol drne3 for the diethyl analogue. Under favourable experimental conditions, dialkylphosphorodithroates can be collected from aqueous solutrons at concentrations not exceeding 1 pg crnm3 (ca. 5 X 10" mol dme3), with extraction efflcrencies of 86-95%. Dialkylphosphorothioates are extracted much less efficiently; drethylphosphate and inorganic phosphate are not extracted.