Industrial Consultancy & Sponsored Research (IC&SR) , IIT Madras

Method for Selective Extraction of Gold by Niacin

Technology Category/Market

Chemical Technology: Extraction of Gold.

Industry: Chemicals, Electronics, Healthcare; Applications: Nanomedicines, Imaging, sensors, Probes, catalysts, Life-sciences

Market: The global gold nanoparticles market

size was USD4.4 billion in 2021 and expected to register a revenue CAGR of 12.6% during the forecast period (2022 to 2030).

Targeted Industries

Watermarking IP design,

Electronic circuits

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Problem Statement

  • 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.

Key Features/Value Proposition

Technical Prospective:

  1. Raw material comprises waste samples including chemical wastes, electronic wastes and laboratory Nano-wastes, and precipitation occurs at room temperature.
  2. The niacin precipitates and recovers about 5% of gold in 2 minutes from an electronic waste composed of Au, Cu and Ni.

Industrial Prospective:

  1. The present invention discloses a fast precipitation and extraction method of gold in waterby a simple biomolecule, niacin, which is cost effective & efficient.
Questions about this Technology?

Contact for Licensing

Research lab

Prof. Pradeep T;

Department of Chemistry

Intellectual Property

  • IITM IDF Ref. 2100;
  • Patent No. 374251
  • PCT/IN2021/051021

Technology Readiness Level

TRL- 3/4

Proof of Concept Ready & tested and validated in Laboratory stage.  

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