Global Patent Index - EP 1061144 A1

EP 1061144 A1 20001220 - Method of preparing high purity gold from precious metal bearing nitrate solutions

Title (en)

Method of preparing high purity gold from precious metal bearing nitrate solutions

Title (de)

Verfahren zur Herstellung von Gold hoher Reinheit aus nitrathaltigen Edelmetall-Lösungen

Title (fr)

Procédé pour obtenir de l'or de pureté élevée à partir de solutions de nitrates des métaux précieux

Publication

EP 1061144 A1 20001220 (DE)

Application

EP 00111133 A 20000524

Priority

DE 19928028 A 19990618

Abstract (en)

[origin: DE19928028C1] High purity gold recovery from nitrate solution involves nitrate decomposition and gold recovery from the resulting highly acidic solution by ferric ion addition. High purity gold is recovered from nitrate-containing precious metal solution by: (a) nitrate decomposition to obtain a solution with \-4 mol/l H<+> ion concentration; and (b) gold ion reduction by addition of an acidic Fe<2+> solution having a \-4 mol/l H<+> ion concentration. Preferred Features: Step (a) is carried out using formic or ascorbic acid at 80-90 deg C, and step (b) is carried out under potential control at 60 deg C.

Abstract (de)

Es wird u. a. ein Verfahren zur Herstellung von Gold hoher Reinheit aus nitrathaltigen Edelmetall-Lösungen vorgestellt, mit folgenden Schritten: a) Nitratzerstörung in der Edelmetall-Lösung, b) eine Gold-Ionen-reduzierende Zugabe einer sauren Fe<2+>-Lösung, deren Konzentration an H<+>-Ionen mindestens 4 mol/l beträgt, zur in Schritt a) aufbereiteten Lösung, deren Konzentration an H<+>-Ionen mindestens 4 mol/l beträgt.

IPC 1-7

C22B 11/00; C22B 3/44; C22B 3/46; B22F 9/24

IPC 8 full level

B22F 9/24 (2006.01); C22B 3/20 (2006.01); C22B 3/44 (2006.01); C22B 3/46 (2006.01); C22B 11/00 (2006.01)

CPC (source: EP US)

C22B 11/00 (2013.01 - EP US); C22B 11/04 (2013.01 - EP US)

Citation (search report)

  • [A] EP 0073108 A1 19830302 - PERRIN ROBERT HENRY
  • [Y] DATABASE WPI Section Ch Week 199339, Derwent World Patents Index; Class E36, AN 1993-309447, XP002147907
  • [YA] DATABASE WPI Section Ch Week 200012, Derwent World Patents Index; Class M25, AN 2000-135514, XP002147908
  • [Y] DATABASE WPI Section Ch Week 199801, Derwent World Patents Index; Class M25, AN 1998-004405, XP002147909

Designated contracting state (EPC)

CH DE FR GB IT LI

DOCDB simple family (publication)

DE 19928028 C1 20000817; DE 50004219 D1 20031204; EP 1061144 A1 20001220; EP 1061144 B1 20031029; US 6331200 B1 20011218; ZA 200003019 B 20010109

DOCDB simple family (application)

DE 19928028 A 19990618; DE 50004219 T 20000524; EP 00111133 A 20000524; US 59512300 A 20000616; ZA 200003019 A 20000615