New patent makes for environment-friendly leaching

2nd August 2016 By: Megan van Wyngaardt - Creamer Media Contributing Editor Online

JOHANNESBURG (miningweekly.com) – Canadian junior Iberian Minerals has filed a patent for its HM X-leach formula to reduce the gold industry’s sustainability challenges in terms of reduced grades, more complex ores and increasingly stringent environmental conditions.

The patent, which will be marketed by Iberian’s new, 100%-owned subsidiary HMX Solutions, is an environment-friendly, non-cyanide-based leach formula for the extraction of precious metals from ore, concentrates, tailings and electronic waste.

“Within industry, the use and disposal of cyanide present significant safety and environmental challenges. The primary challenge in devising a suitable substitute for cyanide in gold processing lies in developing an equally effective and degradable leach reagent, which is not a persistent environmental toxin,” the company said in a statement.

As gold cyanidation rates are relatively slow, the industry has been searching for faster gold-leaching reactions capable of facilitating high metal recovery rates. Alternative lixiviants, or leaching agents, should also be inexpensive and recyclable, selective, nontoxic and compatible with downstream recovery processes.

Iberian highlighted that there was an increasing interest in finding new alternatives or improving previously tried processes. “Numerous other chemicals have been tested to leach gold, but the HM X-leach formula is more cost effective and productive method,” it stated.