Ammoniacal leaching of roast reduced deep-sea manganese nodules

The influence of ultrasound and microwaves on extraction of copper, nickel, and cobalt from manganese deep-sea nodules by reductive ammoniacal leaching in the presence of ammonium thiosulfate as a reducing agent was studied. The ultrasonic ammoniacal leaching provides higher metals extraction, while the effect of microwaves on the metals extraction under the studied leaching conditions is insignificant. In general, increasing leaching temperature increases significantly extraction of the metals of interest. At high temperatures, extraction efficiencies of copper, nickel, and cobalt decrease over longer leaching duration as a result of decomposition of the metals amino-complexes and reverse precipitation of metals. However, during the ultrasonic leaching at a temperature of 85 °C, the extraction of nickel remains almost unchanged over longer leaching durations and does not follow the decreasing course, observed in the extraction of copper and cobalt. The finding suggests that nickel can be selectively extracted from the nodules by the ultrasonic leaching. The maximal extraction efficiency of copper, nickel, and cobalt was 83%, 71%, and 32%, respectively, when the reductive ultrasonic ammoniacal leaching was carried out at 85 °C for 90 min. In the presence of microwaves, the maximal extraction efficiency of copper, nickel, and cobalt was 67%, 48%, and 8%, respectively, when the reductive ultrasonic ammoniacal leaching was carried out at the output power of 60 W for 210 min.

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V.—Manganese in the Sea

Mineralogical Magazine and Journal of the Mineralogical Society ◽

10.1180/minmag.1876.001.2.06 ◽

1876 ◽

Vol 1 (2) ◽

pp. 50-53 ◽

Cited By ~ 1

Author(s):

A. H. Church

Keyword(s):

Chemical Analysis ◽

Deep Sea ◽

The Other ◽

Manganese Nodules ◽

Red Clay ◽

Chemical Examination ◽

Sea Bottom ◽

Ample Supply

To the geologist, the mineralogist and the chemist, two of the observations made during the voyage of the Challenger are of especial interest. One of these observations is the occurrence over vast areas of the deep sea bottom of a peculiar red clay, containing silica, peroxide of iron, and alumina. The other discovery to which I refer has been described by Sir Wyville Thomson as the occurrence throughout this red clay of nodules of “nearly pure peroxide of manganese.” To these nodules, as well us to the red clay, an organic origin has been assigned. But the immediate source of so much manganese is hard to find, for this element is by no means an abundant constituent of animal or vegetable organisms. The difficulty is, however, somewhat lessened when the manganese nodules are submitted to a more minute chemical examination. From two correspondents I have received an ample supply of these curious concretions, accompanied by a suggestion that they should be submitted to chemical analysis.

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Reductive Leaching of Metal Oxides in Hydrometallurgical Processing of Nickel Laterite Ores, Deep Sea Manganese Nodules, and Recycling of Spent Batteries/Catalysts

Sustainability in the Mineral and Energy Sectors ◽

10.1201/9781315369853-10 ◽

2016 ◽

pp. 173-187 ◽

Cited By ~ 1

Author(s):

Gamini Senanayake ◽

Alexander Senaputra ◽

L. C. S. Dharmasiri ◽

Dong-Jin Kim ◽

S. M. Shin ◽

...

Keyword(s):

Metal Oxides ◽

Deep Sea ◽

Manganese Nodules ◽

Nickel Laterite ◽

Hydrometallurgical Processing ◽

Laterite Ores ◽

Reductive Leaching

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Sponge and coral communities of potential mineral resources in the deep-sea: An overview

10.7287/peerj.preprints.26551 ◽

2018 ◽

Author(s):

Tina Molodtsova ◽

Christopher Kelley ◽

Lénaick Menot ◽

Les Watling

Keyword(s):

Deep Sea ◽

Slow Growth ◽

Mineral Resources ◽

Ore Deposits ◽

Manganese Nodules ◽

Cumulative Impact ◽

Mining Sites ◽

Intensive Exploitation ◽

Coral Communities ◽

Hard Substrata

Depletion of commercially valuable minerals on land and increased need of such resources for modern electronics and manufacturing is attracting more and more attention to deep-sea mineral deposits such as cobalt crusts, manganese nodules, phosphorites, polymetallic sulfides and even deep-sea ooze. In a few years we expect intensive exploitation in the deep-sea. Being suspension feeders, corals and sponges associated with hard substrata in potential mining sites would be adversely impacted by deep-sea mining. Deep-sea corals and sponges are characterized by extremely slow growth rates and, as can be seen from fishery impacts, they may take decades to centuries to restore. At the same time, they serve as a substrate, shelter and food for a number of associated deep-sea organisms, thus increasing the cumulative impact of their loss. We summarize here the available data on coral and sponge communities of solid deep-sea ore deposits and possible mechanisms driving their diversity.

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Studies on the dry chlorination of deep sea manganese nodules

Metallurgical Transactions B ◽

10.1007/bf02657755 ◽

1988 ◽

Vol 19 (3) ◽

pp. 514-518 ◽

Cited By ~ 2

Author(s):

B. V. R. Murthy ◽

B. R. Reddy ◽

G. N. Srinivasan ◽

D. N. Dey ◽

P. K. Jena

Keyword(s):

Deep Sea ◽

Manganese Nodules

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Structure and Composition of Micro-Manganese Nodules in Deep-Sea Carbonate from the Zhaoshu Plateau, North of the South China Sea

Minerals ◽

10.3390/min10111016 ◽

2020 ◽

Vol 10 (11) ◽

pp. 1016

Author(s):

Hengchao Xu ◽

Xiaotong Peng ◽

Kaiwen Ta ◽

Taoran Song ◽

Mengran Du ◽

...

Keyword(s):

South China Sea ◽

South China ◽

Deep Sea ◽

Carbonate Rocks ◽

The South China Sea ◽

Coralline Algae ◽

Manganese Nodules ◽

The South ◽

Raman Spectrometry ◽

China Sea

The occurrence of deep-sea ferromanganese nodules and crusts on the seafloor is widespread, providing an important resource for numerous metals such as Ni, Co, and Cu. Although they have been intensively studied in the past, the formation of micro-manganese nodules within carbonate rocks has received less attention, despite the considerable amounts of manganese released from the dissolution of the calcareous framework. The micro-petrographic and geochemical characteristics of reef carbonate rocks recovered from the Zhaoshu plateau in the Xisha uplift, north of the South China Sea, were studied using optical microscopy, scanning electron microscopy, confocal Raman spectrometry, and an electron probe micro-analyzer. The carbonate rocks are composed of biogenic debris, including frameworks of coralline algae and chambers of foraminifer, both of which are suffering strong micritization. Within the calcite micrite, numerous micro-manganese nodules were identified with laminated patterns. Mineral and elemental evidence showed that the Mn oxides in the carbonates are mixed with 10 Å vernadite, 7 Å vernadite and todorokite, both of which are closely associated with the carbonate matrix. The micro-nodules were found to have high Mn/Fe ratios, enriched in Ni and Cu and depleted in Co. We infer that theses nodules are mixed type with early diagenetic growth under oxic–suboxic conditions. The re-distribution of manganite within the rocks is likely influenced by micritization of the calcareous framework. We deduce that microbial-associated reduction of manganite induces the formation of diagenetic todorokite similar to nodules buried in marine sediments.

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