Effect of sodium silicate on flocculation of hematite with starch in the presence of calcium

2003-01-01
Sodium silicate is used as a dispersant in the selective flocculation of iron ores with starch as the polymeric floccullant. The mechanism of its dispersive effect on quartz has been reported to be related to its ability to remove coagulants, such as calcium and magnesium ions, from the process water. The interaction between iron oxides and calcium and sodium silicate, which has not appeared in literature, is also an important factor that would contribute to the success of the selective flocculation process. To elucidate the nature of this interaction at pH 11, where selective flocculation of iron oxides is commonly carried out, the effect of calcium and sodium silicate on the flocculation-selective flocculation behavior of hematite was investigated. Abstraction of calcium and adsorption of starch by hematite at different concentrations of sodium silicate and calcium were determined. It was found that calcium silicate precipitates as well as sodium silicate prevented starch adsorption and, therefore, sodium silicate could only be used effectively below 10 mg/L calcium and 1000 mg/L SiO2 concentrations while dispersing a hematite-quartz mixture.
SEPARATION SCIENCE AND TECHNOLOGY

Suggestions

Effect of sodium carbonate on carbothermic formation of hexagonal boron nitride
Akyıldız, Uğur; Sevinç, Naci; Department of Metallurgical and Materials Engineering (2010)
Effect of Na2CO3 on formation of hexagonal boron nitride (h-BN) by carbothermic method has been studied by subjecting B2O3-C and Na2CO3-added B2O3-C mixtures to N2 (g) atmosphere. Na2CO3 amount in the mixtures was changed in the range of 0-40 wt. %. Time and temperature were used as experimental variables. Reaction products were analyzed by XRD and scanning electron microscope. Na2CO3 was found to increase both the amount and the particle size of h-BN similar to CaCO3 [1]. Na2CO3 was found to be less effect...
Effect of Alkaline Treatment and Pre-impregnation on Mechanical and Water Absorbtion Properties of Pine Wood Flour Containing Poly (Lactic Acid) Based Green-Composites
Altun, Yasemin; DOĞAN, Mehmet; Bayramlı, Erdal (2013-09-01)
The effect of surface treatments and wood flour (WF) ratio on the mechanical, morphological and water absorption properties of poly (lactic acid) (PLA) based green-composites were studied. WF/PLA interfacial adhesion was promoted by means of alkaline treatment and pre-impregnation with dilute solution of matrix material. The composite materials were manufactured with twin screw extruder and injection molded samples were used for characterization. According to tensile test results, the inclusion of WF withou...
Effect of some surfactants on SO2-marble reaction
Boke, H; Gokturk, EH; Saltık, Emine Nevin (2002-12-01)
In the polluted atmosphere, sulphur dioxide (SO2) reacts with calcite (CaCO3) in marble producing calcium sulphite hemihydrate (CaSO3.0.5 H2O) and gypsum (CaSO4.2H(2)O). Gypsum develops crust at rain-sheltered surfaces and then, being more soluble, accelerates erosion at areas exposed to rain. Eventually, all these lead to significant deformations in the appearance and structure of marble surfaces. Clearly, some precautions must be taken to stop or at least to slow down this deterioration process which dest...
Effect of hydrogenation conditions on rheological and micro-structural properties of fats
Başkoçak, Altuğ; Mert, Behiç; Department of Food Engineering (2011)
Hydrogenation is one of the most applied techniques in the fats and oils industry to produce wide range of hardened fats with different physical and chemical properties. Each different combination of hydrogenation conditions serves products of different rheological and micro-structural properties. Therefore, the purpose of this study is to examine the effect of different industrially available catalysts on rheological and micro-structural properties of hydrogenated fats. Three different catalysts were used ...
Effect of calcium carbonate addition on carbothermic formation of hexagonal boron nitride
ÇAMURLU, HASAN ERDEM; SEVİNÇ, NACİ; Topkaya, Yavuz Ali (Elsevier BV, 2008-01-01)
Effect of CaCO3 on formation of hexagonal boron nitride (h-BN) was investigated by holding CaCO3 free and CaCO3 added activated carbon-boric oxide mixtures under nitrogen atmosphere at 1500 degrees C for 30-120 min. Amount of CaCO3 addition was varied in the range of 0-50 wt.% of the initial mixture. Products were characterized by powder X-ray diffractometry, FT-IR analysis, quantitative chemical analysis, scanning electron microscopy and BET specific surface area analysis. It was observed that calcium carb...
Citation Formats
A. İ. Arol, “Effect of sodium silicate on flocculation of hematite with starch in the presence of calcium,” SEPARATION SCIENCE AND TECHNOLOGY, pp. 647–659, 2003, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/33267.