Vol.:(0123456789) 1 3 Chemical Papers https://doi.org/10.1007/s11696-019-00915-6 ORIGINAL PAPER Assessment of a Nigerian lead ore potential for industrial value additions by sulfamic acid solution Alafara A. Baba 1  · Rasaki A. Gbadamosi 1  · Abdulrasheed O. Yusuf 1  · Mustapha A. Raji 1  · Abdullah S. Ibrahim 1  · Christianah O. Adeyemi 1,2 Received: 10 April 2019 / Accepted: 23 August 2019 © Institute of Chemistry, Slovak Academy of Sciences 2019 Abstract The potential of a Nigerian lead ore in form of galena and anglesite containing 72.82 wt% Pb, 19.95 wt % S, 3.07 wt% Au and 2.77 wt% As, as major elements was treated by sulfamic acid (H 3 NSO 3 ) solution. The infuence of acid concentration, reac- tion temperature, stirring speed and particle size on the extent of ore dissolution were properly determined. From the results obtained, the dissolution of lead ore increases with increasing H 3 NSO 3 concentration, reaction temperature, stirring speed and decreasing particle size. At a set of experimental conditions (0.75 mol/L H 3 NSO 3 , − 70 + 90 µm, 320 rpm, 70 °C), 68.2% of the initial 10 g/L ore reacted within 120 min. The calculated apparent activation energy of 28.35 kJ/mol with reaction order of 0.758 confrmed and supported the proposed difusion controlled mechanism for the dissolution process appeared to be frst-order relation. The leach liquor at optimal conditions as analyzed by atomic absorption spectrophotometry were found to contain 2861 mg/L (68.2%) Pb 2+ , 270 mg/L (6.44%) Fe 2+ and 185 mg/L (5.34%) Zn 2+ as major species. Keywords Galena · Sulfamic acid · Dissolution kinetic · Leaching · Characterization Introduction Galena (PbS), the most important source of lead is one of the most intensively studied sulfde minerals for industrial value additions (Da silva 2004). It is mostly associated with other minerals such as chalcopyrite (CuFeS 2 ), pyrite (FeS 2 ) and sphalerite (ZnS) (Deer et al. 1999). Galena from which industrial lead metal could be processed is found to have numerous useful mechanical properties such as low melting point, ductility and high density for defned applications. For example, its high density and resistance to corrosion have been exploited in a number of applications such as ballast in sailboat keels, excellent shielding against X-ray and gamma radiation, plumbing and water distribution and its efective material for sound insulation purposes (Baird and Cann 2012). In the past, lead was primarily smelted from galena after being separated from its associated impurities using benefciation techniques, but lead smelting often encoun- tered difculties with environmental control (Silvestre et al. 2009). Recently, hydrometallurgical treatments have received significant attention for the treatment of lead mineral because of the difculties encountered with conventional pyrometallurgical technique. Separation process through pyrometallurgy technique requires short time, but it must be carried out at high temperature characterized with harmful dust production. Hence, the use of hydrometallurgical opera- tion often prevents undesirable emissions of harmful sulphur oxides and dust into atmosphere (Aydogan et al. 2007a). Therefore, to meet the global consumption of purifed lead materials for its continuous use as radiation proof as well as in the production of lead acid battery which accounted for more than 85% of the world lead output, there is need for constant refned production of industrial lead through hydrometallurgical route to sustain production and satisfy the desired market demands. As leaching is an important unit operation in hydrometallurgical process, the selection of an appropriate leaching reagent is benefcial to this pro- cess. Consequently, several leaching reagents have been * Alafara A. Baba baalafara@yahoo.com * Rasaki A. Gbadamosi ademolagbadamosi14@gmail.com 1 Department of Industrial Chemistry, University of Ilorin, Ilorin, Nigeria 2 Department of Science Laboratory Technology, Federal Polytechnic Ofa, Ofa, Nigeria