Manganese

Manganese
Name	Manganese
Atomic number	25
Category	Transition metal
Appearance	Silvery-gray
Phase	Solid
Atomic mass	54.938

Manganese is a chemical element with atomic number 25 and a silvery-gray appearance belonging to the transition metals. It is used extensively in industrial processes, metallurgy, and chemical syntheses, and it plays roles in biological systems and environmental cycles. Major producers and research institutions study its geology, production methods, and health effects through collaborations spanning mining companies, universities, and regulatory agencies.

Characteristics

Manganese exhibits complex electronic structure and variable oxidation states, notably +2, +3, +4, +6, and +7, which influence its magnetic, catalytic, and electrochemical behavior; these properties are examined by laboratories at Lawrence Berkeley National Laboratory, Max Planck Society, Imperial College London, Massachusetts Institute of Technology, and Oak Ridge National Laboratory. Its crystalline allotropes and intermetallic compounds are characterized using instrumentation from European Organization for Nuclear Research, National Institute of Standards and Technology, California Institute of Technology, Argonne National Laboratory, and École Polytechnique. The metal forms oxides and sulfides such as pyrolusite and rhodochrosite, which are subjects of mineralogical studies by Smithsonian Institution, Natural History Museum, London, U.S. Geological Survey, British Geological Survey, and Geological Survey of Finland. Its corrosion behavior and passivation are relevant to standards set by International Organization for Standardization, American Society for Testing and Materials, Deutsches Institut für Normung, Bureau of Indian Standards, and Standards Australia.

Occurrence and Production

Manganese occurs in minerals including pyrolusite, braunite, and rhodochrosite, mined in regions such as Australia, South Africa, Brazil, India, and China, with major companies like BHP, Vale (company), Rio Tinto Group, Glencore, and Anglo American plc involved in extraction. Ore beneficiation, smelting, and alloy production are implemented in plants operated by Nippon Steel, POSCO, ArcelorMittal, Tata Steel, and ThyssenKrupp. Geological formations bearing manganese nodules on the Clarion-Clipperton Zone and continental margins attract interest from research fleets including RV Akademik Mstislav Keldysh, JOIDES Resolution, and agencies such as NOAA, European Space Agency, Japan Agency for Marine-Earth Science and Technology, Geoscience Australia, and Canadian Geological Survey. Trade and commodity markets for manganese ore and ferroalloys are tracked by exchanges and consultancies like London Metal Exchange, S&P Global, International Monetary Fund, World Bank, and OECD.

Isotopes and Chemistry

Manganese has one stable isotope, 55Mn, studied in nuclear physics programs at CERN, Brookhaven National Laboratory, Rutherford Appleton Laboratory, TRIUMF, and GSI Helmholtz Centre for Heavy Ion Research. Radioisotopes such as 52Mn and 54Mn are produced in cyclotrons and reactors for tracer studies by institutions including Paul Scherrer Institute, Argonne National Laboratory, Institut Laue–Langevin, Kurchatov Institute, and Japan Atomic Energy Agency. Complexes of manganese are central to catalytic cycles in synthetic chemistry pursued at Harvard University, University of Cambridge, ETH Zurich, Yale University, and University of Tokyo. Redox chemistry of manganese underpins batteries and oxidation catalysts developed by Tesla, Inc., Panasonic, Samsung SDI, LG Chem, and Siemens. Coordination compounds and cluster chemistry connect to seminal work at Nobel Prize-linked laboratories and researchers associated with Royal Society, American Chemical Society, Japanese Society for the Promotion of Science, Deutscher Akademischer Austauschdienst, and European Research Council.

Applications and Uses

Manganese alloys, especially ferromanganese and silicomanganese, are essential in steelmaking at mills operated by Nippon Steel, ArcelorMittal, POSCO, Tata Steel, and Nucor Corporation to improve strength and toughness; stainless steel and high-strength structural steels rely on these additions in projects like Three Gorges Dam, Burj Khalifa, Channel Tunnel, Panama Canal expansion, and Gotthard Base Tunnel. Manganese dioxide is used in dry cell batteries and in chemical cells produced by Duracell, Energizer Holdings, Panasonic Corporation, Sony Corporation, and Rayovac Corporation. Catalysts and pigments containing manganese compounds are employed in processes and products developed by BASF, Dow Chemical Company, AkzoNobel, PPG Industries, and Sherwin-Williams. Emerging uses in lithium-ion and post-lithium batteries involve research consortia including MIT Energy Initiative, Clean Energy Ministerial, US Department of Energy, EU Horizon Europe, and China National Battery Research Institute.

Biological Role and Health Effects

Manganese is an essential trace element for many organisms and functions as a cofactor in enzymes such as superoxide dismutase and arginase, topics investigated at National Institutes of Health, World Health Organization, Centers for Disease Control and Prevention, Food and Agriculture Organization, and Rockefeller University. Nutritional studies on dietary manganese reference dietary guidelines from U.S. Food and Drug Administration, European Food Safety Authority, National Health Service (UK), Health Canada, and Australian Department of Health. Occupational exposure risks and neurotoxicity, including manganism and Parkinsonian symptoms, are monitored by Occupational Safety and Health Administration, National Institute for Occupational Safety and Health, European Agency for Safety and Health at Work, International Labour Organization, and World Bank programs. Clinical research into manganese metabolism involves collaborations among Johns Hopkins University, Mayo Clinic, Cleveland Clinic, Karolinska Institute, and University of California, San Francisco.

Environmental Impact and Safety

Environmental cycling of manganese through soils, freshwater, and marine systems is studied by agencies and academic groups such as United States Geological Survey, Environmental Protection Agency (United States), European Environment Agency, CSIRO, and Woods Hole Oceanographic Institution. Contamination from mining and industrial discharges prompts remediation and regulation by Superfund programs, Basel Convention frameworks, United Nations Environment Programme, International Maritime Organization, and national ministries like Ministry of Environment (Japan), Ministry of Ecology and Environment (China), and Ministry of Environment, Forest and Climate Change (India). Ecotoxicology of manganese affecting aquatic invertebrates and fish is researched at Scripps Institution of Oceanography, Australian Antarctic Division, National Oceanic and Atmospheric Administration, Fisheries and Oceans Canada, and Institute of Marine Research (Norway). Safety protocols for handling manganese metal and compounds are codified by Occupational Safety and Health Administration, Globally Harmonized System of Classification and Labelling of Chemicals, European Chemicals Agency, National Fire Protection Association, and International Labour Organization.

Category:Chemical elements