Recovery process

1. A process for the recovery of 14 C from organic substances labelled or contaminated with 14 C comprising:

i) adding organic substances labelled or contaminated with 14 C to an acidic aqueous electrolyte containing silver ions as an electrochemically regenerable primary oxidizing species;

ii) subjecting the acidic aqueous electrolyte to an electric potential;

iii) containing the off-gas produced from an anolyte resulting from the electric potential;

iv) optionally converting any CO in the off-gas to CO2;

v) absorbing CO2 from the off-gas using one or more alkaline absorbers; and

vi) recovering the radiolabelled isotope from the products of the electrochemical process resulting from the application of the electric potential; wherein the process is carried out at a slight pressure depression.

2. A process according to claim 1 wherein the acidic aqueous electrolyte comprises silver ions and nitric acid.

3. A process according to claim 1 wherein the organic substances are drugs labelled with 14 C.

4. A process according to claim 1 wherein the alkaline absorber is Ba (OH)2 or Ca (OH)2.

5. A process according to claim 1 wherein the organic substances are subjected to a pre-treatment step comprising heating the organic substances in nitric acid to a temperature at which the organic substances are partially decomposed or rendered more soluble in the electrolyte.

6. The process of claim 1 wherein subjecting the acidic aqueous electrolyte to an electric potential further comprises adding the acidic aqueous electrolyte to an electrochemical cell having a cathode, an anode, an ion-permeable separator between the anode and the cathode forming an anode region and a cathode region within the cell, and mixing the organic substances continuously or periodically with anolyte from the electrochemical cell.

7. A process according to claim 6 wherein gas streams produced at the anode and cathode are combined and passed through a scrubber to remove NOx.