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Roger F. Sebenik

Bio: Roger F. Sebenik is an academic researcher. The author has contributed to research in topics: Molybdenum & Ferromolybdenum. The author has an hindex of 4, co-authored 4 publications receiving 78 citations.

Papers
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Reference EntryDOI
21 May 2020
TL;DR: In this article, the authors present a survey of the Molybdenum chemistry and its application in various areas of industry, such as mining, automotive, agriculture, and economic aspects.
Abstract: The article contains sections titled: 1. Introduction 2. Properties 3. Occurrence 3.1. Minerals 3.2. Deposits 4. Production 4.1. Concentration 4.2. Processing of Concentrate 4.3. Recovery from Spent Petroleum Catalysts 4.4. Recovery during Production of Tungsten Ores 4.5. Production of Molybdenum Metal Powder 4.6. Production of Compact Molybdenum Metal 4.7. Processing of Molybdenum 4.8. Molybdenum-Base Alloys 5. Uses 6. Production of Ferromolybdenum 6.1. Ferromolybdenum Grades 6.2. Raw Materials 6.3. Submerged Arc Furnace Carbothermic Reduction 6.4. Metallothermic Reduction 7. Molybdenum Compounds 7.1. Overview of Molybdenum Chemistry 7.2. Molybdenum Oxides 7.3. Molybdenum Chalcogenides 7.4. Molybdenum Halides 7.5. Molybdates, Isopolymolybdates, and Heteropolymolybdates 7.6. Other Molybdenum Compounds 8. Uses of Molybdenum Compounds 8.1. Catalysis 8.2. Lubrication 8.3. Corrosion Inhibition 8.4. Flame Retardancy and Smoke Suppression 8.5. Pigments 8.6. Agriculture 9. Analysis 10. Economic Aspects 11. Environmental Aspects 12. Toxicology and Occupational Health

35 citations

Patent
03 Oct 1979
TL;DR: In this paper, the ammonium molybdate solution containing phosphate anions is decomposed by digesting at least one water-soluble compound from the group consisting of aluminum, calcium, iron and magnesium in small but effective amounts.
Abstract: Molybdenum is recovered from an ammonium molybdate solution containing phosphate anions by digesting in an ammonium molybdate solution at least one water-soluble compound of at least one metal selected from the group consisting of aluminum, calcium, iron and magnesium in small but effective amounts to precipitate at least about 50% of the phosphate anions for a time sufficient to precipitate the phosphate anion, separating the phosphate precipitate from the ammonium molybdate solution, then acidifying the ammonium molybdate solution with at least one mineral acid selected from the group consisting of sulfuric acid and nitric acid to lower the pH value of the solution to between about 2.5 and about 4.5 to precipitate ammonium polymolybdate, and calcining the ammonium polymolybdate at a temperature below about 750° C. to produce a molybdenum trioxide product.

25 citations

Patent
02 Sep 1983
TL;DR: In this article, a process for recovering metal values from spent hydrodesulfurization catalyst, the process comprising forming in a pressure reactor an aqueous slurry of finely divided spent catalyst and sodium carbonate, the spent catalyst containing by weight about 2 to 10% Mo, up to about 12% V (e.g.
Abstract: A process is provided for recovering metal values from spent hydrodesulfurization catalyst, the process comprising forming in a pressure reactor an aqueous slurry of finely divided spent catalyst and sodium carbonate, the spent catalyst containing by weight about 2 to 10% Mo, up to about 12% V (e.g., about 2 to 10%), about 0.5 to 4% Co, up to about 10% Ni (e.g., about 0.5 to 5%), occluded oil, coke, sulfide sulfur and the balance essentially alumina. The amount of sodium carbonate employed is at least sufficient under oxidizing conditions to convert molybdenum and any vanadium present to soluble Na2 MoO4 and NaVO3 and to neutralize SO3 produced during oxidation, the amount of sodium carbonate being at least that required stoichiometrically. The slurry is heated to a temperature of about 200° C. to 350° C. (e.g., 275° C. to 325° C.) and a pressure of about 800 psig to 2500 psig (e.g., about 1500 psig to 2500 psig) for a time at least sufficient to solubilize the molybdenum and vanadium present, the amount of oxygen employed being over about 1.1 times the stoichiometric amount sufficient to oxidize the metal values and sulfur to the maximum oxidized state, and to oxidize the oil and free carbon to CO2 and H2 O. The solubilized Mo and V are thereafter separated from each other.

17 citations

Patent
14 Mar 1984
TL;DR: In this article, the molybdenum is recovered from an organic material, such as a spent epoxidation catalyst, by heating the material in a stream of non-oxidizing gas at a temperature of at least about 400° C.
Abstract: Molybdenum is recovered from an organic material, such as a spent epoxidation catalyst, by heating the material in a stream of non-oxidizing gas at a temperature of at least about 400° C. to evolve the organic in the gas stream from which it is recovered and to leave a powdery residue containing essentially all of the molybdenum.

4 citations


Cited by
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Journal ArticleDOI
TL;DR: A comprehensive overview of the synthesis, structural polytypes, properties, and applications of bulk, few layer, and single layer MoS2 can be found in this article, where the single layer form has shown significant potential as a semiconductor analogue of graphene.
Abstract: Molybdenum disulphide (MoS2) has been one of the most interesting materials for scientists and engineers for a long time. While its bulk form has been in use in conventional industries as an intercalation agent and a dry lubricant for many years, its two-dimensional forms have attracted growing attention in recent years for applications in nano-electronic applications. Specifically, the single layer form of MoS2 shows significant potential as a semiconductor analogue of graphene. These exciting applications are spread over many fields, from flexible and transparent transistor devices, to low-power, high efficiency biological and chemical sensing applications. This Review Article, for the first time, provides a comprehensive overview of the synthesis, structural polytypes, properties, and applications of bulk, few layer, and single layer MoS2.

293 citations

Journal ArticleDOI
TL;DR: In this article, a review of the application of solvent extraction for treating leach solutions is presented, where solvent extraction is used to extract valuable metals from spent hydrodesulphurization catalysts, such as molybdenum and vanadium.

204 citations

Journal ArticleDOI
TL;DR: A simple hydrometallurgical processing of spent hydrodesulphurization (HDS) catalyst for the recovery of molybdenum using sodium carbonate and hydrogen peroxide mixture was investigated and it was found possible to achieve >99%, adsorption and desorption efficiency.

110 citations

Journal ArticleDOI
TL;DR: In this study, the acute and chronic effects of sodium molybdate and sodium dichromate to Daphnia magna Straus were evaluated and both toxicants inhibited AChE in vivo at concentrations under the respective 48-h LC(50) values.

73 citations

Journal ArticleDOI
TL;DR: In this article, the sources and distribution of Mo speciation in solution and Mo(VI) anions adsorption mechanisms in soils and bed sediments are reviewed and evaluated.
Abstract: Mo is an essential trace element for both plants and animals in low concentrations (<5 ppm). However, provoked by uncontrolled industrial waste releases in freshwater or seawater, it is plausible that excessive availability of soluble Mo(VI) would be potentially toxic. In the environment, soluble Mo(VI) is mainly present in anionic forms of molybdate (MoO4 2−) and/or tetrathiomolybdate (MoS4 2−). The fate and transport of soluble Mo(VI) anions in surface and subsurface aquatic environments is typically controlled by adsorption in acidic soils and sediment. As such, the ability of soils/bed sediments to retain Mo(VI) is a key to determine its general mobility in the aquatic environment. This article reviews the sources and distribution of Mo speciation in solution and Mo(VI) anions adsorption mechanisms in soils and bed sediments, and evaluates the surface adsorption complexation models at the solid-water interface to estimate Mo(VI) anions adsorption in these chemical systems. Mo(VI) anions adsorption mec...

67 citations