The separation of gold alloys by quartation or using purely chemical means damages the environment and involves losses. The acid gold purity only reaches the quality of normal electrolytic gold with considerable effort. In contrast, gold electrolysis using the Wohlwill Process is carried out without difficulties. It is advisable to use suitable anode bags to avoid mechanical contamination of the cathode gold with particles of AgCl. The gold electrolysis operation is simplified by the use of electrochemical dissolving units for preparing completely nitrate-free AuCl3 and electrochemical precipitators to recover gold from the exhausted electrolytes. Exhausted air problems are almost completely avoided since experience has shown that no waste gasses are produced. 

The purity of the anode material for gold electrolysis should lie, if possible, above 950 ‰ Au in order to obtain a good operating life for the electrolytes. For this reason, a significant amount of the material to be separated must be pre -purified. The acid separation process used earlier is completely obsolete and unsuitable because it is too expensive and in every way costly with regard to the quantitative yield and the required quality of the final product. Consider Sn, which interferes even in small quantities and can lead to metal losses. The acid separation process involves costs for exhaust air and waste water at hardly justifiable levels. 

These problems are completely avoided by using electrochemical preseparation. A specific anode alloy is smelted. After an exact, pre-determined time period, the material to be purified has been pre-separated. The gold remains completely at the anode in the form of a skeleton which completely retains its structure until the end. The use of suitable anode bags eliminates gold losses; the pre-separated gold has a purity of 975 - 985 ‰ Au. Ag is obtained as electrolytic fine silver, and Cu can be precipitated by an additional electrolytic process.

All gold alloys can be electrochemically separated. The choice of procedure is determined by the fine gold content and the analytical values of the material to be separated. For information see the following summary:

Alloys for Separation with

1. to appr. 80 ‰ Au are added to the Ag or Cu electrolysis,

2. 80 to 950 ‰ Au are electrochemically pre-separated by the JANUS Process to 975 - 985 ‰ Au,

3. 950 to 999 ‰ Au are refined by the Gold electrolysis, possibly with modifications.

Recovery of the metals in their commercial form using an owned electrochemical separation plant is economically advantageous assuming a crude metal input of at least 20 kg of gold alloys per week. With higher inputs, the economies are even better, whereas smaller amounts are better toll processed at a metals separation company.

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