Quick Routine Acid Digestion of Iron and Copper Ores for ICP-OES or ICP-MS Analysis

In the mining industry there is a large demand for fastroutine digestions for elemental analysis:

• In prospecting for new mining projects or in developing and maintaining existing mines, a large number of mineral samples must be analyzed quickly. These samples consist of ore and dead rock in varying ratios to each other. They are analyzed for geochemical lead elements to provide information to find or trace those geological formations that allow the most profitable mining.
• In process control the refining process needs to be closely controlled. A lot of different types of process samples have to be analyzed with short turnaround time to allow swift reaction to keep the process under optimum conditions. For refining the analytical task is more specific: yield of process steps, quality of separation steps with the smallest possible amount of energy or reagent input.

In the past, fusion methods for the digestion of minerals and specific acid dissolution methods in combination with specialized photometric and electrochemical methods were used in large scale routine laboratories.
With the widespread use of ICP optical or mass spectrometry, modern high-temperature acid digestion becomes more and more attractive in geochemical analysis:

• No additional dissolved solids from fusion reagents. This reduces the load on the ICP sample introduction system and torch.
• Avoiding solid reagents reduces the risk of contamination.
• Streamlined digestion process in closed vessels.

The method described in this application report is suitable for the samples tested and is a good starting point for samples with somewhat different compositions that may require modifications such as the acid mixture.