News

Sodium cyanide major Cyanco partners with cyanide-free precious metals recovery process company Cycladex

Posted on 31 Mar 2021

Cyanco, a leading global producer of sodium cyanide for precious metal extraction worldwide, has announced that it has formed a strategic partnership with Cycladex Ltd, the developer of a newly-patented cyanide free process to rapidly recover gold and silver. The companies have established a funded joint technology development program and a revenue sharing agreement on collaborative projects. Through the partnership, Cyanco says it is able to expand its current set of offerings aimed at the safe and efficient recovery of precious metals from ore. Cycladex, in turn, benefits from Cyanco’s established infrastructure and customer base, enabling it to grow its presence in the mining industry.

Cycladex uses a novel, patented chemical process to recover gold and silver which does not use cyanide, reduces operating and capital costs, reduces gold recovery time scales, uses an estimated 50% less water and helps gold miners avoid land contamination. Gold is leached from the ore using a bromide-based lixiviant that forms a tetrabromoaurate complex with gold. A solution of cornstarch derived α-cyclodextrin is added to the leachate; upon addition of the α-cyclodextrin, the lock-and-key crystal structure forms spontaneously and precipitates. The gold is released from the crystalline precipitate at high temperature to yield solid gold metal.

Developed by Nobel Prize winner, Sir Fraser Stoddart, Director of the Center for the Chemistry of Integrated Systems at Northwestern University, this new process has been proven viable for mining operations that are too remote to receive sodium cyanide, or whose infrastructures or ore characteristics may require a different mineral extraction process. Cycladex recently together with BC Mining of Baja Mexico completed its first demonstration unit which has the capacity to process 24 t/d of gold ore. Together with Triple 7 Mining, a gold company in Arizona US, it has completed scale-up gold ore leaching trials in Arizona running more than 20 batches at pilot scale.

Cyanco President and CEO, Michael Lefenfeld, said: “Cyanco is continually evaluating new technologies with the potential to increase mineral yields for our customers. Each mine is different, with a range of ore characteristics, processing variables, and unique environmental factors,” he said. “Through partnering with Cycladex, we believe we will be able to serve more mining customers – both large and small – by addressing a broader spectrum of mining needs, while continuing to focus on improving process efficiency and lowering operating costs.”

“I am delighted to have entered into this partnership with Cyanco,” said Roger Pettman, Executive Chairman of Cycladex. “Their outstanding reputation in the industry, technical expertise and global distribution network will allow us to expand our technology commercialisation efforts and help us realize our full growth potential. We see many opportunities where the Cycladex technology fits nicely in a product portfolio alongside sodium cyanide,” he added.

Roy Norcross, Director of Cyanco’s Applied Technology and Quality Programs, described the Cycladex partnership as a natural extension for his technical services team. “Cyanco continues to implement advanced technologies that help our customers minimise waste and reduce costs. Adding a promising new mineral recovery technology, like the one developed at Cycladex, to Cyanco’s existing, world-class portfolio gives my team another tool in their toolbox. Together, we can more precisely meet our customer’s diverse mineral processing needs.”

Lefenfeld adds: “This partnership is additive to Cyanco’s long history in making mineral extraction safe for mining customers and the surrounding communities. With Cycladex, Cyanco’s product portfolio continues to expand, cost-effectively opening up new opportunities and markets for both partners.”

Cycladex has been awarded extensive grants by the US National Science Foundation to develop its process and has proven in the field and in the lab that its technology works on ores at more than 30 mines worldwide.