A complete processing method has been experimentally developed at laboratory scale for the future extraction of metlas from manganese nodules. The digestion of the nodules is performed by pressured sulfuric acid leaching at 200° C., nickel, copper, cobalt, and zinc being selectively dissolved in solution along with iron and manganese. The subsequent separation and recovery of the valuable metals is carried out with a combination of ion exchange and precipitation processes. Estimates for this methodology based on an annual throughput of 2 million tonnes of manganese nodules should lead to the production of about 24000 tonnes of nickel, 20000 tonnes of copper, and 3000 tonnes of cobalt and zinc. The authors conclude that, despite all uncertainty regarding the metal processing costs and the future metal prices, the exploitation of manganese nodules is economically viable.

Samples have been dried before analysis.From 1983 until 1989 NOAA-NCEI compiled the NOAA-MMS Marine Minerals Geochemical Database from journal articles, technical reports and unpublished sources from other institutions. At the time it was the most extended data compilation on ferromanganese deposits world wide. Initially published in a proprietary format incompatible with present day standards it was jointly decided by AWI and NOAA to transcribe this legacy data into PANGAEA. This transfer is augmented by a careful checking of the original sources when available and the encoding of ancillary information (sample description, method of analysis..) not present in the NOAA-MMS database.

Supplement to: Neuschütz, D; Scheffler, U; Junghauss, H (1977): Verfahren zur Aufarbeitung von Manganknollen durch Schwefelsäuredrucklaugung = Method for the processing of manganese nodules by sulfuric acid pressure leaching. Erzmetall, 30(2), 61-67