In some copper mines, valuable quantities of gold are present in the ore. Extracting it from the waste from copper refineries requires careful monitoring of the oxidation reduction potential (ORP). In a new white paper, METTLER TOLEDO explains how use of their in-line ORP sensors at a Rio Tinto refinery is increasing gold yield.

The substantial rise in the value of gold over recent years is convincing mining companies to examine how more of the metal can be recovered from their processes. Rio Tinto's Kennecott Utah Copper refinery in the USA operates a precious metals plant where the slimes (residue) from copper anode electro refining undergo treatment to remove precious metals.

In a process called wet chlorination, significant quantities of gold are recovered from the copper slimes. To monitor the process and indicate when complete dissolution of the gold has been reached, engineers employ METTLER TOLEDO in-line oxidation reduction potential (ORP) sensors. Continuous measurement of ORP prevents gold from being left in the process waste, and excessive and costly chlorination.

METTLER TOLEDO's white paper, "More Gold from Slimes - Higher Productivity in Wet Chlorination" explains how use of ORP sensors at Rio Tinto's refinery has increased gold yield and improved wet chlorination efficiency.

The white paper is available at

About Mettler Toledo:
METTLER TOLEDO specializes in the area of precision instruments for professional use. METTLER TOLEDO laboratory instruments are used in research, scientific, drug discovery, and quality control labs, amongst many others in the pharmaceutical, chemical, food and cosmetics industries. METTLER TOLEDO comprehensive industrial solutions cover the various steps in a host of manufacturing processes at many of the same customers that laboratory serves. Solutions range from receiving raw materials through various manufacturing processes, in-line process control and end-of-line packaging control, to logistics and shipping. Increasingly, these solutions are fully integrated into the customer's IT environment, helping automate their workflows. In food retail, our offering for fresh food management ranges from receiving and pre-packaging, to in-store solutions for self-service departments, deli counters, and checkout terminals.

Contact information:
Mettler-Toledo International Inc.
Im Langacher, Zip Code 8606
Greifensee, Switzerland
E-Mail : [email protected]
Phone : +41-44-944 33 85
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