Processing Nigerian pyrolusite ore, Part I: Characterization and dissolution kinetics analysis

CIM Journal, Vol. 7, No. 1, 2016

A. A. Baba and L. Ibrahim
Department of Industrial Chemistry, University of Ilorin, Ilorin, Nigeria

R. B. Bale
Department of Geology and Mineral Sciences, University of Ilorin, Ilorin, Nigeria

A. G. F. Alabi
Department of Materials and Metallurgical Engineering, University of Ilorin, Ilorin, Nigeria (currently Department of Material Science and Engineering, Kwara State University, Malete, Nigeria)

F. A. Adekola
Department of Industrial Chemistry, University of Ilorin, Ilorin, Nigeria

M. K. Ghosh, K. Sanjay, and A. R. Sheik
Hydro and Electrometallurgy Department, Council of Scientific and Industrial Research (CSIR)-Institute of Minerals and Materials Technology, Bhubaneswar, India

http://dx.doi.org/10.15834/cimj.2016.5
Abstract This paper studies the characterization and dissolution of a Nigerian pyrolusite ore, reporting the results of ore physicochemical analyses and detailed ore characterization before and after leaching at optimal conditions. Ore dissolution rate increased proportional to acid concentration and temperature, but decreased with ore particle size. In a 4 M H2SO4 solution at 80°C with a particle size of –90+75 μm and moderate agitation, ore dissolution rate reached 78.7%. Unleached residue produced under optimal leaching conditions consisted of silica with admixtures of cristobalite and stishovite. The calculated activation energy supported the proposed diffusion control mechanism for the process.
Keywords: Characterization, Dissolution kinetics, Leaching, Nigeria, Pyrolusite ore, Sulphuric acid solution
Résumé Le présent article étudie la caractérisation et la dissolution d’un minerai de pyrolusite du Nigeria, il donne les résultats des analyses physicochimiques du minerai et de la caractérisation détaillée du minerai avant et après la lixiviation sous des conditions optimales. Le taux de dissolution du minerai augmentait proportionnellement à la concentration de l’acide mais décroissait avec la taille des particules. Dans une solution 4 M H2SO4 à 80 °C, avec une granulométrie de –90+75 μm et une agitation modérée, le taux de dissolution du minerai a atteint 78,7 %. Les résidus produits sous des conditions optimales de lixiviation étaient constitués de silice avec un mélange de cristobalite et de stishovite. L’énergie calculée d’activation supportait le mécanisme de contrôle de la diffusion proposé pour le procédé.
Mots-Clé Caractérisation, cinétique de dissolution, lixiviation, minerai de pyrolusite, Nigeria, solution d’acide sulfurique
Full Access to Technical Paper
PDF version for $20.00
Other papers in CIM Journal, Vol. 7, No. 1, 2016
Search
Sort By:  Relevance
Showing results 1 - 7
Text
Publication: CIM Journal
Issue: 1
Volume: 7
Year: 2016
Text
Summary: Roof bolts are subjected to axial stresses, shear stresses, or both. Axial and shear stresses were compared between roof bolts machined with two and three slots. Shear stresses perpendicular to and at an angle to the shear planes were evaluated by analyzing a three-slot instrumented roof bolt, performing laboratory tests on two- and three-slot roof bolts, and conducting in-situ test analyses. Three-slot bolts appear to provide a complete bending strain profile, requiring no prior knowledge of...
Publication: CIM Journal
Author(s): K. V. Jessu, T. R. Kostecki, and A. J. S. Spearing
Keywords: Angled double-shear test, Distributed optical sensing (DOS), Double-shear tests, Fibre Bragg grating (FBG)
Issue: 1
Volume: 7
Year: 2016
Text
Summary: This paper reviews the evolving Ontario mining regime for mining industry-Aboriginal engagement and its apparent alignment with court decisions, domestic law, emerging international norms, mining industry rules, and mining firm-Aboriginal agreements, drawing on publicly available commentary from government officials, the private sector, and Indigenous communities. This paper provides a preliminary analysis of the potential implications of the new regime, especially for the mining industry and...
Publication: CIM Journal
Author(s): K. Webb, M. Hohn
Keywords: Aboriginal communities, Consultation, Ontario Mining Act, Stakeholder engagement
Issue: 1
Volume: 7
Year: 2016
Text
Summary: The development curve in the extractive sector has become longer, steeper, and riskier due to increased social, legal, and political risks from various stakeholders. Indigenous peoples are a unique stakeholder because their growing legal rights to lands and resources can often determine a project’s outcome. A project will only be successful if it is able to obtain the legal permits, withstand any judicial reviews, and gain and maintain the social license to operate. Stakeholder identification...
Publication: CIM Journal
Author(s): K. Ramji
Keywords: Aboriginal title and rights; Corporate and social responsibility (CSR); Extractive sector; Impact benefits agreement (IBA); Indigenous peoples; Management and engagement; Risk management; Social, legal, and political risk (SLP); Social license to operate (SLO); Stakeholder identification; United Nations Declaration on the Rights of Indigenous Peoples (UNDRIP)
Issue: 1
Volume: 7
Year: 2016
Text
Summary: Most underground diesel equipment is equipped with diesel oxidization catalysts (DOCs) to reduce carbon monoxide and hydrocarbon emissions. DOCs do not alter nitrogen oxides concentrations but can promote the oxidization of nitric oxide (NO) to the more toxic nitrogen dioxide (NO2). Vale and CanmetMINING have been researching how to reduce worker exposure to diesel emissions by testing mining equipment DOCs. Results indicate a > 77% decrease in carbon monoxide concentration but a 46–315%...
Publication: CIM Journal
Author(s): J. Stachulak, M. Gangal, C. Allen
Keywords: Catalytic converter, Diesel emission, Diesel engine, Diesel oxidation catalysts (DOCs), Load haul dump (LHD), Mine air quality, Nitrogen oxides (NOx), Total hydrocarbon concentrations (THC), Underground mines, Ventilation
Issue: 1
Volume: 7
Year: 2016
Text
Summary: This paper compares Canadian provincial mining safety regulations regarding the use and testing of cage safety catches, including a brief history and evolution. Regulations are similar across provinces, with only slight variations. Currently, the “Ontario-type” safety dog is the most commonly used safety catch in Canada. Performance estimation of the compensation mechanism for different safety-dog shapes and tooth angles show this shape works well and has consistent braking results, but the...
Publication: CIM Journal
Author(s): B. Galy and L. Giraud
Keywords: Cage, Deceleration, Free fall, Hoist, Mining safety, Performance, Regulation, Safety catches, Safety dogs
Issue: 1
Volume: 7
Year: 2016
Text
Summary: The potential for mudrushes is a potential hazard that should be evaluated during cave mining studies. Mudrushes are a phenomenon that can have very different origins, but produce the same results: injury, loss of life, damage to property, excess dilution, production delays, or mine closure. Although mudrushes are more common in cave mines than other mines, any mining activity that enables the accumulation of fine particles and water is susceptible to mudflow. This paper describes the process...
Publication: CIM Journal
Author(s): J. Jakubec, R. Clayton, A. R. Guest
Keywords: Cave mining, Mudflow, Mudpush, Mudrush, Risk, Wet muck
Issue: 1
Volume: 7
Year: 2016
Powered by Coveo Enterprise Search