Authors: Saodat Mirzajonova, Matluba Muratova, Ulugkhoja Rakhmatov, Nargiza Lutfullayeva, Gulnoza Beknazarova, Zaynobiddin Matkarimov, Sokhibjon Matkarimov
Abstract: The article provides information about the initial elements in the waste and tailings of the copper processing plant of the Almalyk Mining and Metallurgical Combine and theoretical solutions for the extraction of metals. According to chemical data, the amount of iron in the waste is high (52.6%), and the most effective solution for extracting iron from the waste is the reduction process. An increase in the amount of iron to 88.9% was formed using coal and lime as reducing agents.
103
Authors: Jaroslava Szucsova, Adriana Zelenakova, Lubos Nagy, Michael Barutiak, Eva Benova, Vladimir Zelenak, Vlasta Zavisova
Abstract: Magnetic-bead separation or purification serves as a technique for effective isolation of biomolecules. In presented work we prepared and characterized core-shell magnetic nanoparticle samples consisted of Fe3O4 core coated with SiO2 shell. Samples were subsequently coated with ligands MPTMS (3-(mercaptopropyl)trimethoxysilane), CPTMS (3-(chloropropyl)trimethoxysilane) and MMSP (3-(trimethoxysilyl)propyl methacrylate) with aim to increase the number of active centers for specific binding with RNA. Such samples were further investigated for their magnetic properties, size, and morphology. Magnetic properties were studied in DC field up to 5 T in temperature range 5 – 300 K. Size and morphology were determined from SEM micrographs and elemental compositions of the samples were investigated using EDX analysis. Modification of nanoparticle surface with different ligands leads to modification of active centers on the SiO2 surface on which the DNA and RNA molecules can be bounded. It also causes the change in magnetic and structural properties of nanoparticles.
91
Authors: Waleed R. Abdullah
Abstract: This study was carried out to determine the possibility of reducing the iron oxide ratio in silica sand from Ardhumah, an area, (18) km west of Rutba, a city in Al-Anbar Governorate, to obtain sand specifications appropriate for making colorless glasses (not exceeding 0.02 % iron oxide ratio). The reduction process of iron oxide includes three stages; the first stage is magnetic separation to reduce Fe2O3 from 0.092% to 0.040%, the second stage is re-floatation which has reduced Fe2O3 to 0.024%, finally treatment of the sand output from the first and second stage with diluted HCl or H2SO4, this study showed the possibility of obtaining silica sand with a ratio of Fe2O3 up to 0.016%.
77
Authors: Irina V. Loginova, Aleksei V. Kyrchikov
Abstract: In Russia, the main feedstock for producing aluminum is bauxite. During the processing of 1 ton of bauxite into alumina (Al2O3), up to 0.5–0.6 ton of techno-genic waste is formed, that is red mud. It is not currently disposed of and accumulated in mud tailing dumps. It contains valuable components: Al – 8 %; Fe – 25 %; Ti – 2.4 % and it can be considered as a potential raw material for ferrous metallurgy and as a source of vanadium, titanium, and rare-earth elements (REE) Sc, Y, La. The paper shows the possibility of obtaining red mud with an increased iron content of up to 36 %, with an additional extraction of aluminum. Red mud from the Ural Aluminum Plant (Russia) is considered. It is proposed to direct this mud to the production of pellets for the production of cast iron. To extract aluminum from red mud, it is proposed to process the mud in a highly alkaline medium by sintering in the temperature range 300–600 °C. The resulting sinter is leached with water or a slightly alkaline solution with the conversion of aluminum compounds into solution. The red mud, obtained this way, exhibits magnetic properties. A magnetic separation was carried out, and the yield of the magnetic fraction is 79.87 %. The iron content increases by 25 % and amounts to 51.88 % of Fe2O3.
673
Authors: Chiaki Uyeda, Keiji Hisayoshi, Kentaro Terada
Abstract: Magentic separation generally required strong magnetic forces induced in ferromagnetic or strong paramagnetic particles; in order to realize the separation in diamagnetic or weak paramagnetic particles, it was necessary to attach magnetic beads or magnetic ions to induce the strong magnetic force. A method to separate mixture of weak magnetic particles by its concentration of paramagnetic ferrous ion is newly proposed, which does not require the abovementioned magnetic attachments. The efficiently of the new method is experimentally examined using a pocketsize magnetic circuit (4.5 cm x2.0 cm x 1.0 cm) and a piece of cross sectional paper (5.0 cm x1.0cm). The separation is based on a principle that velocity of a translating particle, induced by a magnetic volume force in an area of monotonically decreasing field, is uniquely determined only by its magnetic susceptibility (per unit mass) of the particle; the velocity is independent to mass of particle. By examining the spectra of the separated particles recovered on the cross sectional paper, a histogram on Fe concentration is easily obtained for the particles without the need of consuming them.
105
Authors: Nur Khuzaima, Khairel Rafezi Ahmad, Nur Hidayah Ahmad Zaidi, M.K.R. Hashim, Sheikh Abdul Rezan
Abstract: Valuable minerals are defined as mineral which having good opportunities to economic and consireable important. The most commonly occurring sand mineral deposits are ilmenite, rutile, magnetite, cassiterite, monazite, tourmaline, zircon, kyanite, silimanite, and garnet. In Malaysia, mineral sand deposits is found in Langkawi which known as black sand Langkawi. Langkawi black sand having high amount of valuable minerals that is very crucial in the industrial and construction products. Characterizations of black sand acquire different techniques to concentrate and separate valuable minerals. These techniques utilize different in physical or chemical properties of the valuable and gangue (wastes) minerals. For magnetic is based on natural or induced differences in magnetic susceptibility or conductivity of the minerals.. They are used to distinguish and extract magnetic, slightly magnetic and non-magnetic components present in the heavy fraction (Rutile, Ilmenite, Magnetite, Garnets, Zircon and Monazite). All minerals will have one of three magnetic properties: ferromagnetic, paramagnetic and diamagnetic. Ferromagnetic minerals (i.e. Magnetite and Ilmenite) are magnetic and easily attracted to the poles of magnet. Paramagnetic and diamagnetic minerals in the group magnetic, but if the mixture of paramagnetic and diamagnetic minerals are passed through a magnetic field, the paramagnetic minerals will be pulled into the field and diamagnetic minerals separated from the field. By varying the intensity of the magnetic field, it is also possible to separate different paramagnetic minerals from each other. In this study, techniques used to separate valuable minerals from black sand are magnetic separator.
440
Authors: Myung Hee Song, D. Harikishore Kumar Reddy, John Kwame Bediako, Shuo Lin, Yeoung Sang Yun
Abstract: Magnetic MnFe2O4 nanoparticles (MNPs) were fabricated and entrapped in amine-rich chitosan (CS) sorbents containing multi-walled carbon nanotubes (MWCNTs) or polyethyleneimine (PEI). Magnetic polymer composite sponges (MPCSs) and magnetic polymer composite fibers (MPCFs) were prepared through mixing each of MWCNT and PEI with MNPs-CS solution. The successful fabrication of MPCSs and MPCFs was confirmed through FTIR and VSM analyses. The as-fabricated MPCSs and MPCFs were used for adsorptive recovery of Pt (IV) from acidic solution. The maximum uptakes of Pt (IV) ions by the MPCSs and MPCFs were estimated to be 218.2 ± 8.3 and 371.4 ± 16.8 mg/g, respectively. Moreover, the Pt (IV)-loaded MPCSs and MPCFs were easily separated from aqueous solution under magnetic field after sorption process.
311
Authors: Noorzahan Begum, Norsaffirah Norsaffirah, Nur Khuzaima, Md. Fazlul Bari, Shekh Rezan
Abstract: Processing of Langkawi black sand for the recovery of metals had been carried out in this study. The samples were characterized after sieve analysis. Magnetic separator is used to separate between magnetic and non-magnetic portion of blank sand. XRF and FTIR were used to know the metal content in black sand. Before magnetic separation black sand contain about 43.2 wt% SiO2, Al2O3 with 21.1 wt% and Fe2O3 with 17.2 wt% and 12.0% TiO2.
63
Authors: Janka Mihalčová, Miroslav Rimár
Abstract: The contribution deals with use of semi-automated method of magnetic separation of particles in order to control mechanical system of aircraft engines. There are three levels of machine wear characterized by means of wear debris particle analysis in the lubrication system of aircraft engines. The shape and size of wear debris particles formed due to machine wear arise immediately in case of wear change thus this method is extremely suitable to control mechanical system washed by lubricant. Analysis of actual samples of lubricating oils containing several types of wear debris at the same time resulted in finding out and characterizing the levels of wear, from standard up to critical one. The contribution describes typical types of aircraft engine lubrication system wear with allocation of the wear level to particular pictures of wear debris particles.
136
Authors: Qiu Yue Wang, Yan Wu, Yong Huo Li, Xiang Yang
Abstract: The average grade of iron ores in China is around 32%, about 10% lower than the world’s average level. In order to alleviate the demand of iron ore for steelmaking industries, it is urgent to develop a highly efficient, energy-saving, low-carbon and environment-friendly technology. The goethite ore from Northern Hainan Island was studied via reduction magnetization by pine, rice chaff, and corn straw biomass fuels. The magnetic properties and magnetic separation were discussed by optimizing the parameters of roasting temperature, roasting time, and the ratio of biomass fuels. The results show that we could obtain concentrated iron ore grade of pine roasting and magnetic separation grade of iron concentrate 61.64% with the recovery of 79.75% via pine fuel roasting, 61.75% with the recovery 80.16% via rice chaff, and 61.47% with the recovery of 81.28% via corn straw roasting. Thereby, we could deduce that biomass fuels for reduction roasting of low goethite ore is promising to substitute the traditional coal and coke fossil fuels.
235