Developments in Gold Leaching: A Literature Survey

The gold industry has seen intense activity in the areas of exploration and metallurgy'in recent years. Many developments have taken piace through which ore bodies that were once considered uneconomical to exploit are becoming economical grade. Even the traditional cyanidation process has been modified during the course of time to make it more economical and efficient. Developments such as heap leaching, in-situ leaching, carbon-in-pulp (CIP), carbon-in-leach (CIL) resin-in-pulp (RIP), and pretreatment of refractory ores have already made an impact on gold industries. Research and development work is also being carried out on less toxic, more efficient lixiviants which may eventually replace the toxic cyanide, solving the disposal problem currently facing the industry. This paper aims at summarizing the developments in the extraction of gold using conventional, as well as unconventional, lixiviants. Some developments in the area of gold recovery from pregnant solutions have also been briefly discussed.