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EN
Many industries, especially mining and metallurgy, deal with solutions containing ions. In some cases, these metal ions need to be concentrated and recovered from solutions and sometimes removed from wastewater. The ion flotation method has been applied for wastewater and water treatment, recovery of precious and platinum group metals, preconcentrating of rare earth elements, selective separation of multicomponent ions from dilute solutions, and analytical chemistry. It has been employed to separate heavy metals from a liquid phase using bubble attachment, originated in mineral processing. In these cases, ion flotation has an important place among other methods because it is a cheap and practical method. In this study, many ion flotation studies, especially applied at laboratory scale, were reviewed. This method gives very successful and promising results in removing heavy metals with toxic effects from wastewater and selective separation of metal ions from very low concentrated solutions. Ion flotation may take place in industrial scale operations with the new developments in flotation machines and collectors with better selectivity, high efficiency, lower cost, and environmental friendliness.
EN
In this study, the effect of frother was investigated in two and three phases in the systems of the flotation. While the two-phase system consisted of liquid and gas, the three-phase systems contained a chalcopyrite ore. The study of three-phase systems was performed with the ore on a laboratory and plant scale. Effect of the amount and type of the frothers, their mixtures, and pH were examined depending on the bubble size, grade of the concentrate, and the recovery of chalcopyrite flotation. The results showed that as the amount of frothers increased, there was a reduction in the bubble size in all experiments. Additionally, the frother mixtures gave a positive effect on the chalcopyrite flotation. One of the most important purposes of flotation frothers shrinks the air bubble. As can be understood from the tests this time reduction of the frothers bubble size has a positive effect on the flotation. Likewise, it increases the foam stable value. It is observed from this study that increasing the amount of frothers decreases the surface tension and bubble size at different pH.
EN
In this study, flotation tests were conducted with purified pyrite and ore samples. The collectors employed were anionic and cationic type such as potassium ethlyl-amyl xanthate, Tomamine M73 and Resanol Bal. According to the flotation tests, it was found that pyrite floated at low pH and depressed at high pH values with xanthates. On the other hand, in the case of cationic collectors which are Tomamine M73 (alkyl ether amine, an amphoteric surfactant) and Resanol Bal (N-3-tridecyloxy propyl 1-3 diamine, branched acetate) pyrite floated at high pH values. It was shown that amine type collectors could be efficient to selectively float pyrite from chalcopyrite at alkali pH ranges in the case of ore samples.
EN
Nepheline syenite, which is a silica-poor crystalline rock, competes with feldspar in applications such as glass, ceramic filler, and pigment industries. While its appearance is medium coarse granular like granite, main differences between them are nepheline syenite is silica poor, and contains high alumina and alkali content. Turkey has considerable nepheline syenite deposits in Kırşehir Region, and they contain 1.3% Fe2O3 on average, thus cannot be used unless beneficiated by flotation or/and magnetic separation. In this paper, physical and physicochemical experiments were carried out to improve the quality of nepheline syenite ore. After determinations of chemical, mineralogical, and properties of the sample, three different technologies such as flotation, magnetic separation, and leaching were applied on the ore sample, separately and combined. The obtained results showed that the magnetic separation alone could not produce a nepheline syenite concentrate assaying 0.45% Fe2O3. It was not also possible to obtain a nepheline concentrate less than 0.25% Fe2O3 adapting optimum flotation conditions. The best results were found in combination of the high intensity wet magnetic separation and flotation between -212+63 μm particle size, and a final concentrate with 0.20% Fe2O3 and 0.01% TiO2 was obtained. The leaching experiments were conducted to further decrease Fe2O3 content. Finally, a saleable nepheline syenite concentrate for tile, sanitary ware, electrode, glass, and fiberglass industries was obtained with 6.63% K2O, 9.02% Na2O, 0.15% Fe2O3, and 0.01% TiO2 by the weight of 63.9% at the end of the experiments.
EN
The worldwide consumption of wollastonite has been increasing from day to day. It is a calcium metasilicate with the chemical formula CaSiO3. Wollastonite is the only naturally occurring, nonmetallic, white mineral that is needle-shaped in a crystal habit. Due to its high chemical and thermal resistance and nontoxic properties, wollastonite replaces asbestos. Apart from this, the acicular property of wollastonite allow it to compete with other acicular materials where improvements in dimensional stability, flexural modulus and heat deflection are sought. Due to its unique properties such as: its high brightness and whiteness, low moisture and oil absorption, low volatile content, and acicular properties, it is used also as a filling material for ceramics, plastics and paints, thermal and electrical insulator, wetting agent and smelter for glaze. Three methods are used for the beneficiation of wollastonite: mechanical sorting, dry or wet magnetic separation and flotation. Magnetic separation and flotation can be applied together in some cases. In this study, flotation has been investigated for the selective separation of calcite-rich wollastonite ores from the Buzlukdağ deposit, in the Kırşehir-Akpınar region, in the middle of Anatolia. The mineralogical analysis of the sample used in the study shows that the ore sample contains 60–62% wollastonite (CaSiO3), 4–5% augite (Ca,Na)(Mg,Fe,Al)(Si,Al)2O6, 30–32% calcite (CaCO3) and minor amount of other minerals. As a result of this study, the wollastonite concentrate which contains 0.44% Fe2O3, 52.71% SiO2, 87.85% wollastonite with 0.60% loss on ignition (using 1500 g/t potassium oleate) was obtained. The ultimate grade concentrates of calcite that can also be obtained as by-products are with 99.80% calcite content and 85.4% recovery.
PL
Światowe zużycie wollastonitu ciągle wzrasta. Wollastonit jest metakrzemianem wapnia o wzorze chemicznym CaSiO3. Jest jedynym naturalnie występującym, niemetalicznym, białym minerałem, który ma kształt igieł o pokroju kryształu. Wollastonit ze względu na wysoką odporność chemiczną i termiczną oraz właściwości nietoksyczne zastępuje azbest. Poza tym igiełkowa właściwość wollastonitu umożliwia konkurencję z innymi igiełkowymi materiałami, w zakresie poprawy stabilności wymiarowej, modułu zginania i ugięcia pod wpływem ciepła. Ze względu na swoje unikalne właściwości, takie jak: wysoka jasność i biel, niska wilgotność i absorpcja oleju, niska zawartość części lotnych i właściwości igiełkowe, umożliwia zastosowanie jego jako: materiału wypełniającego do ceramiki, tworzyw sztucznych i farb, izolatora termicznego i elektrycznego, środka zwilżającego i pieca do glazury. Do wzbogacania wollastonitu stosowane są trzy metody: sortowanie mechaniczne, separacja magnetyczna na sucho lub mokro oraz flotacja. W niektórych przypadkach można zastosować zarówno separację magnetyczną, jak i flotację. W tym artykule zastosowano flotację w celu selektywnego oddzielania rud kalcytu i wollastonitu ze złoża Buzlukdağ w regionie Kırşehir-Akpınar w centrum Anatolii. Analiza mineralogiczna próbki użytej w badaniu pokazuje, że próba rudy zawiera 60–62% wollastonitu (CaSiO3), 4–5% augitu (Ca, Na)(Mg, Fe, Al)(Si, Al)2O6, 30–32% kalcytu (CaCO3) i niewielką ilość innych minerałów. W wyniku tych badań uzyskano koncentrat wollastonitu, który zawiera 0,44% ‒ Fe2O3, 52,71% ‒ SiO2, 87,85% wolastonitu przy stratach wynoszących 0,60% (przy użyciu 1500 g/Mg oleinianu potasu). Końcowe koncentraty kalcytu, które można również otrzymać jako produkty uboczne, zawierają 99,80% kalcytu i 85,4% odzysku.
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