Beneficiation of Seafloor Massive Sulfides by Liquid-Liquid Extraction

Author(s):  
Yasuharu Nakajima ◽  
Yuta Yamabe ◽  
Toyohisa Fujita ◽  
Gjergj Dodbiba

Abstract This paper addresses the applicability of liquid-liquid extraction for separating mineral particles by the difference in oil-water partition coefficient, for the seafloor mineral processing of Seafloor Massive Sulfides (SMSs). Measurements of contact angle of sulfide mineral – aqueous solution – oil systems under high-pressure conditions were performed to evaluate the efficiency of liquid-liquid extraction at high pressures. The results showed that the contact angle stayed around 80 - 100° at the pressure range up to 16MPa; and the changes in the contact angles were within 5° with varying pressure. Extraction experiments were carried out by using particles of an SMS ore, which contained Zinc (Zn), Lead (Pb), and Barium (Ba) in the grade of more than 10 mass% and Copper (Cu) in a small percentage, to evaluate the beneficiation performance of liquid-liquid extraction. In the experiments, extraction conditions such as the dosage of chemical reagents, and pH in the aqueous solution were varied to optimize both the recovery and selectivity of Cu, Zn, and Pb in the oil phase, and those of Ba in the water phase. The experimental results showed that the optimum condition was 200 g/t dosage - pH 7, where the grade and recovery were ca. 37 mass% and ca. 90 mass%, respectively. The beneficiation performance of liquid-liquid extraction would be comparable to that of flotation, adapted to the processing of other SMS ores.

Author(s):  
Yasuharu Nakajima ◽  
Joji Yamamoto ◽  
Tomoko Takahashi ◽  
Blair Thornton ◽  
Yuta Yamabe ◽  
...  

Abstract Seafloor Massive Sulfides have been expected to be future mineral resources. The grade of valuable metallic elements in ores of Seafloor Massive Sulfides is usually small percentage. If valuable minerals can be extracted from the ores on deep seafloor, the total mining cost can be reduced significantly. The authors proposed Seafloor Mineral Processing, where ores are to be ground into fine particles and separated into concentrates and tailings on seafloor. The Seafloor Mineral Processing system consists of processing units for unit operations such as grinding and separation. To investigate the applicability of flotation, which is a method to separate ore particles by using the difference in wettability of minerals, to the separation unit, measurements of contact angles of sulfide minerals at high pressures were carried out. The results suggested that the contact angles of the minerals would have relationships with pressure in depending on the kind of minerals and solutions. In addition, applying Laser-Induced breakdown Spectroscopy (LIBS), an optical method for elemental analysis, to measurement of metal grade of ore particles handled as slurry in the processing units was also investigated. Signals assigned to copper, zinc, and lead were successfully detected in the spectra obtained from ore particles in slurry flow.


2013 ◽  
Vol 10 (3) ◽  
pp. 997-1004
Author(s):  
Baghdad Science Journal

Liquid-Liquid Extraction of Cu(II) ion in aqueous solution by dicyclohexyl-18-crown-6 as extractant in dichloroethane was studied .The extraction efficiency was investigated by a spectrophometric method. The reagent form a coloured complex which has been a quantitatively extracted at pH 6.3. The method obeys Beer`s law over range from (2.5-22.5) ppm with the correlation coefficient of 0.9989. The molar absorptivity the stoichiometry of extracted complex is found to be 1:2. the proposed method is very sensitive and selective.


2019 ◽  
Vol 64 (6) ◽  
pp. 2350-2356 ◽  
Author(s):  
Conghua Yi ◽  
Wenli Song ◽  
Yulei Zhang ◽  
Xueqing Qiu

2013 ◽  
Vol 41 (6) ◽  
pp. 3319-3334 ◽  
Author(s):  
Mohamed Khoutoul ◽  
Farid Abrigach ◽  
Abdelkader Zarrouk ◽  
Nour-Eddine Benchat ◽  
Morad Lamsayah ◽  
...  

Author(s):  
Gen Matsuura ◽  
Hidehira Fukaya ◽  
Emiyu Ogawa ◽  
Sota Kawakami ◽  
Hitoshi Mori ◽  
...  

Background: Local impedance (LI) can indirectly measure catheter contact and tissue temperature during radiofrequency catheter ablation (RFCA). However, data on the effects of catheter contact angle on LI parameters are scarce. This study aimed to evaluate the influence of catheter contact angle on LI changes and lesion size with 2 different LI-sensing catheters in a porcine experimental study. Methods: Lesions were created by the INTELLANAV MiFi™ OI (MiFi) and the INTELLANAV STABLEPOINT™ (STABLEPOINT). RFCA was performed with 30 watts and a duration of 30 seconds. The CF (0, 5, 10, 20, and 30 g) and catheter contact angle (30°, 45°, and 90°) were changed in each set (n=8 each). The LI rise, LI drop, and lesion size were evaluated. Results: The LI rise increased as CF increased. There was no angular dependence with the LI rise under all CFs in the MiFi. On the other hand, the LI rise at 90° was lower than at 30° under 5 and 10 g of CF in STABLEPOINT. The LI drop increased as CF increased. Regarding the difference in catheter contact angles, the LI drop at 90° was lower than that at 30° for both catheters. The maximum lesion widths and surface widths were smaller at 90° than at 30°, whereas there were no differences in lesion depths. Conclusion: The LI drop and lesion widths at 90° were significantly smaller than those at 30°, although the lesion depths were not different among the 3 angles for the MiFi and STABLEPOINT.


Author(s):  
Magomed Pashevich Dokhov

The article uses the thermodynamics of interfacial phenomena to justify the fact that Young’s equations can correctly describe the three-phase equilibrium with any type of interatomic bonds. Wetting, adhesion, dissolution, surface adsorption, and other surface phenomena are important characteristics, whichlargely determine the quality and durability of materials, and the development of a number of production techniques, including welding, soldering, baking of metallic and non-metallic powders, etc. Therefore, it is important to study them.Using experimental data regarding surface energies of liquids (melts) and contact angles available in the literature, we calculated the surface energies of many solid metals, oxides, carbides, and other inorganic and organic materials without taking into account the amount of the interfacial energy at the solid-liquid (melt) interface. Some researchers assumed that in case of an acute contact angle the interfacial energy is low. Therefore, they neglected it and assumed it to be zero.Others knew that this value could not be measured, that is why they measured and calculated the difference between the surface energy of a solid and the interfacial energy of a solid and a liquid (melt), which is equal to the product of the surface energy of this liquid by the cosine of the contact angle. It is obvious that these methods of determining the surface energy based on such oversimplified assumptions result in poor accuracy.Through the use of examples this paper shows how the surface energies of solids were previously calculated and how the shortcomings of previous calculations can be corrected


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