19-23 ALKYLIMINODIMETHYLENEPHOSPHONIC ACID, A NEW EXTRACTANT FOR GOLD FROM ACIDIC THIOUREA SOLUTIONS

19-23 Alkyliminodimethylenediphosphonic acid (H4L), a new extractant, which combines the amine functional group with a phosphonic acid functional group through a single easily synthesized compound, promises to simplify, as well as to lower, the cost of the use of dual synergistic extractants in extracting gold from acidic thiourea solutions. Experimental results showed that extraction of gold from acidic thiourea solutions with H4L could be as high as 99.4% while stripping with dilute solutions of sulphuric acid was in the range of 98.9-99.2%. The composition of the species formed by gold with the extractant was found to be 1:2 between Au and H4L.