Fecl3.6h2o

EXAMPLE 2

Iron has been used as an example of a metal whose presence in aqueous solution requires the use of acid to avoid the formation of iron hydroxide and the precipitation of the metal ion.

0.015 g of FeCl₃.6H₂O (supplied by Alfa Aesar) was dissolved in 50 mL at 10 M HCl (supplied by Roth). The solution was yellow. 1 ml of this solution was mixed with 0.25 g of [P₄₄₄₁₄][Cl] (supplied by Cytec) at 25° C. A biphasic composition was obtained, comprising:

• • a yellow upper phase: the phase enriched in ionic liquid φ_IL comprising Fe(III), and
  • an almost colorless lower phase: the phase enriched in water φ_W.

The partition coefficient of the Fe(III) metal ion between the two phases φ_IL and φ_W was
K(Fe(III))_n=[Fe(III)]φ_IL/[Fe(III)]φ_W>750

Fe(III) was quantitatively extracted with acidic ABS [P₄₄₄₁₄][Cl]—HCl—H₂O. More than 99.7% of the Fe(III) is extracted from the acidic aqueous phase as measured by flame absorption spectroscopy.

Example 27

FeCl₃.6H₂O (50 g, 184 mmol, Alfa Aesar, 97%) was placed in a flask and dissolved in 300 mL of H₂O (J.T. baker, HPLC grade). To that solution, D-(−)-quinic acid (110 g, 572 mmol, Buchlr Gmbh, 96%) was added slowly with continuous stirring. The pH of the solution was adjusted to ˜3 by addition of 10M KOH (Alfa Aesar, 85%) (˜80 mL was required).

The dark yellow solution darkened to brownish upon addition of KOH. The dark solution was stirred for 1 h at room temperature. After stirring at room temperature for 1 h ethanol (EMD, 94%) (2.5 l) was added slowly to the solution with stirring.

After addition of approximately ¼ of the total ethanol, the solution lightened visibly and a fine solid began to precipitate from solution. After addition of the remaining ethanol, the solution is allowed to sit overnight at room temperature.

The solids are collected by vacuum filtration on a fritted funnel and allowed to dry on the funnel while the vacuum is continued for 2-3 h. The bright yellow solid is spread in a thin layer in a drying dish and dried open to the air for 3 days followed by drying under vacuum for 48 h to give 155 g of the final product.

Example 27

FeCl₃.6H₂O (50 g, 184 mmol, Alfa Aesar, 97%) was placed in a flask and dissolved in 300 mL of H₂O (J.T. baker, HPLC grade). To that solution, D-(−)-quinic acid (110 g, 572 mmol, Buchlr Gmbh, 96%) was added slowly with continuous stirring. The pH of the solution was adjusted to ˜3 by addition of 10M KOH (Alfa Aesar, 85%) (˜80 mL was required).

The dark yellow solution darkened to brownish upon addition of KOH. The dark solution was stirred for 1 h at room temperature. After stirring at room temperature for 1 h ethanol (EMD, 94%) (2.5 l) was added slowly to the solution with stirring.

After addition of approximately of the total ethanol, the solution lightened visibly and a fine solid began to precipitate from solution. After addition of the remaining ethanol, the solution is allowed to sit overnight at room temperature.

The solids are collected by vacuum filtration on a fritted funnel and allowed to dry on the funnel while the vacuum is continued for 2-3 h. The bright yellow solid is spread in a thin layer in a drying dish and dried open to the air for 3 days followed by drying under vacuum for 48 h to give 155 g of the final product.