Nickel and cobalt acid leaching from a low-grade South African saprolitic laterite using sulphuric acid was studied. Ore characterisation was performed by XRD and XRF.Batch agitation leaching tests were conducted at atmospheric pressure investigating main parameters: particle size and percent solids at 25 °C and 90 °C. Ore …

The leaching efficiency of Xiangxi manganese oxide ore reached 99.8% under the optimal condition which was determined as follows: manganese oxide ore to waste tea mass ratio of 10:1, sulfuric acid concentration of 1.7 mol/L, liquid-to-solid ratio of 7.5:1, leaching temperature of 368 K, time of 8 h.

Highlights Leaching temperature, leaching duration, sulfuric acid to ore weight ratio and particle size of the limonitic nickel laterite ore were studied. Optimum parameters determined as 255 o C, 0.30 sulfuric acid to ore weight ratio, a particle size of −850μ, 1 h of leaching duration with 30% w/w. 87.3% of Ni and 88.8% of Co in the …

Optimal acid/ore ratio for ilmenite leaching was determined to be 2:1 (w/w) at an optimal reaction time of 3 h. Generation of a large amount of sulfuric acid waste is a drawback of the sulfuric acid process. ... As with weak acids, leaching in alkaline medium also extracts comparatively more titanium than iron, but requires an additional acid ...

Leaching of gold and silver from the gold-bearing ore using amino acids of microbial origin (reproduced from Groudev et al., 1999). Pintail's research in Colorado (USA), in partnership with the Science Applications International Corporation (SAIC), proposed the BioLix TM process to extract gold and silver using biologically derived …

the contact between ore and acid solution in the subsequent leaching process [16–20]. Li et al. [21] of Central South University studied the hydrochloric acid leaching process of laterite nickel ore by activation roasting. After roasting for 1 h at 300 C, under the condition that the concentration of

Serbia (the approximate Cu content in the ore ranges from 0.2 - 0.3 % with >10 % copper in the form of oxide minerals). The leaching experiments were performed using sulphuric acid solutions, whereby the kinetics of copper leaching was investigated with respect to acid concentration and solid to liquid ratio. The copper concentration in

Acid leaching is commonly performed by agitating an ore-leach mixture for 4 to as long as 48 hours at ambient temperature. Except in special circumstances, sulfuric acid is the leachant used; it is supplied in amounts sufficient to obtain a final leach liquor at about…

To understand the effect of 4 h acid leaching on ore mineralogy and chemistry, the feed and leached solid products obtained at different temperatures were characterized (Fig. 1, Fig. 2 and Table 2).The XRD patterns of the feed ore and the solid residues obtained at 70 and 95 °C showed that the mineralogy was mainly composed of …

The leaching of talc ore was investigated in the presence of various acids, i.e., HF, HCl, HNO 3, H 2 SO 4, H 3 PO 4, aqua regia, H 3 BO 3, and CH 3 COOH. The acid leaching experiment was initially carried out for 60 min at ambient temperature (about 30 °C), using 100 mL of 5% acid solution for a 5-g talc sample.

HPAL (High-Pressure Acid Leaching) is one of the important technologies for extracting nickel and cobalt from nickel laterite ore. In the next few years, some plants using this technology will be operated in Indonesia. The production will be estimated to be 543,000 tons per year by 2025.

In this study, an alternative method for recovering nickel and other valuable metals from nickel laterite ores is proposed and evaluated. The proposed method comprises a leaching step using citric acid to dissolve the nickel and cobalt from Indonesian nickel laterite ores, and subsequently, an oxalate precipitation step to precipitate the nickel (and …

The two main types of leaching are heap and insitu leaching. Heap Leaching. Heap leaching is also known as acid leaching. This method is most effective for the extraction of metals from difficult ores, and is one of the most tried and tested methods. The pre-processing of ore before leaching involves the grinding and roasting of the ore.

The recovery of zinc from a flotation tailing using 17-different leaching agents, including inorganic and organic acids, alkaline solutions and chelating agents, was investigated. The effects of the lixiviant type, acid concentration, leaching temperature, leaching time, and solid-to-liquid ratio on the metals dissolution were studied.

Under the conditions of the ratio of mixed acid of 5 mol/L HCl + 1 mol/L HF, leaching temperature of 353.15 K, and leaching time of 12 h, the SiO 2 purity of high-grade silica reached 99.51%, and the removal efficiency of Fe, Al, Mg, and Ca from quartz concentrate was 95.20%, 85.60%, 97.99%, and 97.19%, respectively. During the …

If there are no other economic elements within the ore a mine might choose to extract the uranium using a leaching agent, usually a low molar sulfuric acid. Similar to copper oxide heap leaching, also using dilute sulfuric acid. The final product is yellowcake ((U_3O_8)) and requires significant further processing to produce fuel-grade feed.

The leaching reagent (dilute sulfuric acid) is sprayed through sprinklers on top of the heap pile and allowed to trickle down through the heap, where it dissolves the copper from the ore. The resulting "pregnant" leach solution of sulfuric acid …

Operating data from aerated heaps leaching ore crushed to 12 mm (80% passing) have indicated a value for k of slightly less than 0.001 d-1 (Liu and Hashemzadeh, 2016). According to Eq. ... The model was deployed to investigate the leaching kinetics of an oxide copper ore by sulphuric acid. Ultimately, the velocity field, mineral leaching …

Sulphuric acid leaching has been used in the treatment of lateritic ores for the recovery of nickel and cobalt therefrom. However, in order to obtain good extraction from these ores, prolonged treatment using acid of high strength and also using high pressures and recycling steps have been necessary. In the improved method of the invention nickel …

Earlier, a patent was claimed by Coleman and Jaffa 61 to produce Li 2 CO 3 from an amblygonite ore (8.63% Li 2 O) using caustic soda digestion and sulfuric acid leaching. Firstly, a mixture of the ore and NaOH solution was digested at ∼93 °C for 3 h to produce a slurry containing dissolved aluminum phosphate and an insoluble lithium-rich ...

The results of ore leaching with sulfuric acid showed that the degree of recovery of cobalt increased from 7.3 to 35.2% with an increase in the H 2 SO 4 concentration from 0.5 to 2 N. Iron, potassium, calcium, manganese, and zinc sulfates also transit to the liquid phase along with cobalt. The transition of copper and aluminum is …

Acid Leaching. The experimental work on the oxidized copper ore at the New Cornelia mine at Ajo, Ariz., ended on Jan. 12, 1916. On that date final decision was made on the general nature of the process to be used in the 5,000-ton leaching plant, and on many of the details, as far as experience on a 40-ton scale could decide them.

The leaching efficiency was estimated. The mass of residues varied from 50 to 90 % of the mass of starting material. It depended on the type of lixiviant and the mineral composition of ore. When chloric acid was used as a leaching solution the mass of residue was 50–70 %, with sulphuric acid: 80 % and with alkaline solution - 90 %.

Surprisingly, citric acid and sulfuric acid were more effective in nickel than other acid solutions, providing motivation for the potential use of citric acid in nickel …

1. Introduction1.1. Occurrence and characteristics of chalcopyrite. Much of the world's economic copper resource occurs as chalcopyrite (CuFeS 2), commonly at low grades (≤ 0.5% Cu).Chalcopyrite is the dominant Cu ore mineral in most porphyry deposits, which make up an estimated 70% of the global Cu resource (Singer, 2017), and is also …

In short, acid leaching is used widely in sandstone-type uranium deposits in many countries because of its high uranium leaching efficiency and low cost of leaching solution production [[9], [10], [11]]. During the acid-leaching process, the fluid characteristics of uranium-bearing sandstones are different from those of conventional reservoirs.

R. A. D. Pattrick, G. H. Kelsall and D. J. Vaughan Article Metrics Get access Cite Rights & Permissions Abstract The kinetics and mechanisms of dissolution of the …

acid consuming minerals are more likely to consume additional acid during normal leaching times than larger particles. Thus, size plays an important role in observed acid consumption. Figure 1. Schematic diagram of ore leaching with three different types of acid consuming minerals after some exposure to acidic leaching

Uranium leaching is the process by which the uranium is extracted from the raw ore by reacting the material with acid or base. Fig. 2 shows a general process flow for the uranium extraction process. Prior to the leaching …

Parr stirred reactors are widely used in hydrometallurgical applications where acid leaching of ores is the preferred method to extract metal ions. A widespread example of this technology is the acid …