• In the present era, it is necessary to recover gold from waste including nano waste and electronic waste to meet the growing demand of the metal.
• There are a few methods used for recovery of gold, as discussed in the prior art, which are Expensive, time consuming and unsustainable.
• The present invention overcomes the above-mentioned deficiencies by providing an environment-friendly solution.

Present Patent describes a method for selectively precipitating and extracting gold in aqueous solutions and the method comprises of steps given below:

1. Adding conc. HCl and HNO3 in 3:1 ratio to the gold bearing raw materials to get dissolved gold solution of HAuCl4.

2. Adding saturated niacin in water to the dissolved gold solution HAuCl4 to precipitate [AuCl4] – [2Niacin+H] + complex.

3. Filtering the obtained precipitate of the second step to remove impurities.

4. Adding a reductant to the recovered [AuCl4] – [2Niacin+H] + complex of third step to reduce the complex and to extract gold metal.

Thus, niacin selectively precipitates and recovers gold from gold containing acidic mixtures at concentrations as low as 300ppb.

The other ions in the solution can be any common ion such as sodium, calcium, aluminum, etc.