Research Report RR:E01-1111
This ASTM Research Report covers interlaboratory testing of the Acid Neutralization Potential Acidity (ANPA) titration for ores and related materials to be included in the E-1915 series of methods which for the standardized static testing used for the prediction of acid rock drainage (ARD) and metal leaching (ML). The titration method is a simplified, automatable version of the Modified Sobek neutralization potential titration methods which eliminates the need for the qualitative fizz rating by using the pH and carbonate carbon content of the sample to select the proper acid digestion conditions for the test samples. A total of eight laboratories participated in the interlaboratory testing which used calibration mixtures containing sand and calcium carbonate to set quality control limits for implementation of the method and five certified reference materials which can be used to verify proper method implementation. A limited number of laboratories also measured acid-base accounting reference materials for bias determination.
E1915-20 Standard Test Methods for Analysis of Metal Bearing Ores and Related Materials for Carbon, Sulfur, and Acid-Base Characteristics
Committee E01 on Analytical Chemistry for Metals, Ores, and Related Materials
Subcommittee E01.02 on Ores, Concentrates, and Related Metallurgical Materials