11:30, June 26, 2026

The new method makes it possible to increase the extraction efficiency of precious metals by 20% or more

Ural Federal University specialists have created a gold extraction technology for ore in Russia and other countries. The technology was tested on minerals from the Malomir mine (Amur Region, Russia), and the extraction efficiency of the precious metal increased by 22 %. Currently, the technology is being tested on ore from Uzbek mines. A description of the new method was published in the Hydrometallurgy journal.

“We work with complex and stubborn ores. Such ores currently constitute a significant part of the world’s reserves. They are accumulated and obtained in Russia, Kazakhstan, Uzbekistan, Kyrgyzstan, and many other countries. Ores are either not involved in processing or are processed in limited quantities due to their complex structure, composition, mineralogy, and unprofitability. Such ores are processed to a limited extent — for example, in China — but not always using environmentally friendly methods and not always cost‑effectively, as the main goal is to increase gold reserves,” explains Denis Rogozhnikov, Head of the UrFU Laboratory of Advanced Technologies for the Complex Processing of Mineral and Man‑Made Raw Materials of Non‑Ferrous and Ferrous Metals.

UrFU specialists develop environmentally friendly integrated methods that, on the one hand, do not leave harmful waste and, on the other, are economically profitable. Thus, the efficiency of the technology tested on ore from the Malomir mine was increased with lignosulfonate — a high‑tonnage, cheap, and safe substance, a waste product from pulp and paper production and a by‑product of wood processing. In this case, adding lignosulfonate to the process increased the amount of gold extracted from 68 % to 90 %.

“We are trying to ensure that stubborn ores can be processed in Russia without harming the environment and, of course, with economic benefits. Due to the involvement of such facilities in the processing, the economic effect for enterprises engaged in gold mining can reach tens of millions of dollars,” adds Denis Rogozhnikov.

The ore from the Malomir mine is gold‑bearing sulfide ore of refractory type. Similar ores with comparable mineral compositions are also found in Uzbekistan, the USA, Mali, Ghana, Kazakhstan, and Kyrgyzstan. Generally, today a significant proportion of the world’s native gold reserves consists of refractory ores.

Today, there are several technologies for processing complex ores and concentrates: pyrometallurgical methods, atmospheric and bacterial oxidation, autoclave technologies, etc. The UrFU specialists’ technology relates to the hydrometallurgy of carbonaceous concentrates, specifically to atmospheric leaching using nitric acid with the addition of surfactants. During ore processing, nitric acid is recycled (regenerated), and dangerous substances such as arsenic are converted into a safe form, making the process environmentally friendly. Additives (in this case, lignosulfonates) increase the extraction efficiency of precious metals in this new method.

Reference

The use of new technologies for processing refractory ore is usually more expensive than traditional methods. However, given the high prices for precious metals and the continuing price increases on global markets, these technologies can ensure the profitability of production. Additionally, the world’s reserves of “simple” gold are depleting, and companies will eventually turn to more advanced technologies for processing complex raw materials.

Anastasia Pyankova

Ural Federal University is one of the leading universities in Russia founded in 1920. UrFU is located in Yekaterinburg, the capital of the Ural region, an economic, industrial, scientific and cultural center of Russia. The university is the project office of the Ural Interregional Research and Education Center "Advanced Industrial Technologies and Materials" designed for solving tasks of "Science" National Project.