High pressure acid leaching of turkish laterites

Download
2011
Kaya, Şerif
The aim of this thesis study was to investigate and find the most cost effective way of extracting nickel and cobalt into the pregnant leach solution (PLS) from Gördes lateritic nickel and cobalt ore by means of sulphuric acid leaching under high temperature and high pressure conditions.The high pressure acid leach (HPAL) experiments were conducted with nontronitic and limonitic types of Gördes lateritic nickel ore, respectively. Leaching experiments of nontronite ore have shown that almost all of the nickel and cobalt contained in the nontronitic ore were easily extracted into the (PLS). Therefore, the rest of the experiments were concentrated on difficult to leach limonitic sample when compared with the nontronitic one, and higher nickel and cobalt extractions were aimed to be obtained. By taking economic and technical considerations into account, the basic (HPAL) process parameters for the limonitic sample were optimized as; leaching at 255 °C with a particle size of 100% -850 μ with 0.30 sulphuric acid to ore weight ratio in 1 hour of leaching duration. The experiments were conducted with 30% solids ratio and it was found that 87.3% of nickel and 88.8% of cobalt present in the limonitic ore could be extracted into the pregnant leach solution. Nevertheless, these results were found to be below the desired values. Therefore, the possible reasons of this behavior were investigated and the presence of hematite mineral in the limonitic ore was found to be the most probable one. Therefore, in order to dissolve the nickel and cobalt present in the hematite mineral, the additions of HCl, ferrous ions, cuprous ions and sulphur were tried, respectively and they were found to be beneficial in order to increase the degree of nickel and cobalt extractions

Suggestions

High pressure acid leaching of a refractory lateritic nickel ore
MUTLU KAYA, SEVCAN; Topkaya, Yavuz Ali (2011-09-01)
This paper describes the experimental findings of the extraction of nickel and cobalt by high pressure acid leaching (HPAL) of a refractory limonitic nickel laterite ore from the Gordes region of Manisa in Turkey. By optimizing the basic HPAL process parameters: leaching at 255 degrees C with 0.30 sulfuric acid to ore weight ratio with a particle size of 100%-850 mu for 1 h of leaching, it was found that 87.3% of nickel and 88.8% of cobalt present in the ore could be extracted into the pregnant leach soluti...
Pressure leaching of Sivrihisar-Yunus Emre nickel laterites
Seçen, Berk; Topkaya, Yavuz Ali; Department of Metallurgical and Materials Engineering (2011)
The aim of this thesis study was to extract nickel and cobalt from Sivrihisar limonitic nickel laterite ore by high pressure acid leaching (HPAL) method under most economical operating parameters. Optimizing the conditions to yield a saleable quality mixed hydroxide product from the pregnant leach solution (PLS) was also investigated. To extract high amounts of nickel and cobalt from the laterite matrix; leaching duration, leaching temperature and sulfuric acid/ore ratio were studied at fixed conditions of ...
Acid curing and baking of bastnaesite ore and concentrate
Topkaya, Yavuz Ali (1999-01-01)
In this study, the hydrometallurgical evaluation of a rare earth ore as well as a concentrate obtained from this ore was done in the laboratory. For the mentioned study, a bastnaesite type rare earth ore located in Beylikahir in Turkey was used. The total rare earth oxide (REO) content of the deposit was estimated to be 1 million tons with an average concentration of 3.42% REO. The rare earths were contained in bastnaesite mineral. The other constituents of the ore were calcium fluoride (52.5%), barite (25....
High hydrostatic pressure assisted extraction of pectin from sugar beet pulp
Kaya, Burcu; Okur, İlhami; Alpas, Hami; Oztop, Mecit Halil (2021-05-01)
This study aimed to investigate the effect of high hydrostatic pressure assisted extraction (HHPE) (250, 350 and 450 MPa at 40 degrees C for 5 min with/without acid addition) of pectin from sugar beet pulp and compare its properties with pectin obtained from conventional extraction (CE). Degree of esterification (DE), galacturonic acid (Gal-A) content, Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR) relaxometry experiments were performed on the obtained pectin powder. HHP...
Pressure leaching of Çaldağ lateritic nickel ore
Önal, Mehmet Ali Recai; Topkaya, Yavuz Ali; Department of Metallurgical and Materials Engineering (2013)
The purpose of this study was to investigate the process optimization of combined high pressure acid leaching (HPAL) and mixed hydroxide precipitation (MHP) route for the extraction of nickel and cobalt from Çaldağ lateritic nickel ore. In order to extract nickel and cobalt values into pregnant leach solution (PLS), several process parameters of HPAL including acid load, temperature, leaching duration and particle size were investigated in comparative manner at constant solid concentration and agitation spe...
Citation Formats
Ş. Kaya, “High pressure acid leaching of turkish laterites,” M.S. - Master of Science, Middle East Technical University, 2011.