Collector Reagent Research Articles

Flotation performance and adsorption mechanism of styrene phosphonic acid as a collector to synthetic (Ce,La)2O3

The flotation performances of styrene phosphonic acid (SPA) to synthetic (Ce,La)2O3 (REO), calcium fluorite (CaF2) and fluorapatite (Ca5F(PO4)3) were investigated by flotation tests, flotation of synthetic mixed mineral, the surface adsorption capacity and the polarizing microscopy to solve the flotation separation problem of rare earth oxides from roasted concentrate. The flotation test results indicated that compared with CaF2 and Ca5F(PO4)3, SPA exhibited superior collecting performance to direct flotation recovery of REO and floated out above 90% REO at pH 3–6. However, the collecting ability of SPA to CaF2 and Ca5F(PO4)3 was extremely weak and the highest recovery was only 20% at pH 2–11. The flotation of synthetic mixed mineral showed that SPA was a good collector reagent for flotation of synthetic REO at pH 5, so REO, CaF2 and Ca5F(PO4)3 could be separated from roasted concentrate by using SPA as a collector. The surface adsorption capacity tests and polarizing microscopy results confirmed that SPA was adsorbed on REO surface, while CaF2 and Ca5F(PO4)3 were not. The adsorption mechanism of SPA to synthetic REO was studied by solution chemistry analysis of collector, the ζ-potential tests, infrared spectroscopy and X-ray photoelectron spectroscopy (XPS) analyses. The results indicated that SPA was physically adsorbed onto REO surface, which exhibited excellent flotation selectivity to REO against CaF2 and Ca5F(PO4)3.

Recuperación de iones cobre por flotación con amilxantato de potasio

In this paper a study about the column flotation process of copper ion employing potassium amylxanthate as collector reagent is carried out. The effect on the recovery of copper ion by the modification of variables such as collector/metal relation and surface velocity of gas and liquid was determined experimentally by the analysis of the statistic-mathematical model of the copper flotation process, as well as the physico-chemical phenomena that take place, showing the effect of the collector/metal relation in the process. The effect of pH as the main properties of the chemical system in the recovery and the kinetic of the flotation process is made too. The experimental results shows that the recovery of copper in the pH range of 4,5 - 12 is possible with prevalence of precipitate flotation.

Changes in the structure of water induced by PAV-1 flotation reagent

The action of PAV-1 surfactant with anionic-cationic molecular structure is considered. Flotation is intensified if PAV-1 is supplied prior to the collector reagent. Adding PAV-1 activator in amounts of 0.2–1.0 g/t increases the yield of flotational concentrate by 1.5–3.2% (depending on the ash content of the coal slurry supplied for flotation), with simultaneous reduction in collector consumption by 20–25%.

A mixture of tris(propenyl)phosphinoxides: A new effective collector reagent for copper-nickel ore flotation

The properties of a new collector reagent (SF-239) based on a mixture of tris(propenyl)phosphinoxides have been studied with respect to the flotation of copper-nickel ores. For the flotation of chalcopyritecubanite ores, the new collector gives a 1.82% increase in copper yield into the concentrate as compared to a butyl aeroflot collector.

Studies on the influence of a flotation collector reagent on iron ore green pellet properties

The properties of iron ore green pellets with varying additions of a surface-active flotation collector reagent (Atrac) were studied by small-scale balling. The compression strength and plasticity were measured with a semi-automatic measuring device and the pressure curves were saved and subjected to further mathematical treatment. The green pellet breakage was also filmed with a high-speed camera. Adding Atrac to the pellet feed seriously damaged the quality of green pellets, even in small dosages. This is because an increasing amount of air bubbles became so strongly attached on the particle surfaces that they could not be removed during compaction by balling. The adsorption of air in green pellets was seen as an increase in porosity and a decrease in the filling degree (proportion of pores filled with water). Both the wet and dry compression strength decreased. The air bubbles behaved in wet green pellets like large, plastic particles and the plasticity increased beyond an acceptable level. Breakage started inside the green pellets, along the air bubbles, and generated multi-breakage patterns in wet as well as dry green pellets. Green pellet breakage to crumbs instead of a few distinct segments, promotes the generation of dust and fines and leads to lower bed permeability in the pelletizing machine. The results show that the decrease in iron ore green pellet wet strength in the presence of surface-active agents is not fully described by the so called Rumpf equation, where surface tension and contact angle are used as variables to describe the capillary forces. The green pellet breakage in the presence of air bubbles took place by crack propagation along pore structures rather than through the loss of the capillary forces.

Mutual Separation and Determination of Th(IV) and U(VI) Using Arsenazo III as a Dye Collector Reagent by Flotation‐Spectrophotometric Method

AbstractThis paper reports a simple and highly selective method for the separation, preconcentration, and determination of trace amounts of thorium and uranium in some complex samples via staircase flotation. The method is based on the initial flotation of the Th(IV)‐arsenazo III complex in the presence of U(VI) from a solution of 5 mol dm−3 HCl, then reduction of U(VI) to U(IV) and repetition of the flotation step. In both steps, the floated complex was dissolved in a 5‐mL portion of methanol and its absorbance was measured at 655 nm, spectrophotometrically. For a 30‐mL portion of the sample, Beer's law was obeyed over the concentration ranges of 3.40 × 10−7to 3.06 × 10−6 mol dm−3 for Th(IV) and3.40 × 10−7 to 3.40 × 10−6 mol dm−3 for U(IV) with the apparent molar absorptivity of 4.20 × 105 dm3 mol−1 cm−1 and 3.59 × 105 dm3 mol−1 cm−1, respectively. The RSDs (n = 7) corresponding to 1.7 × 10−6 mol dm−3 of Th(IV) and U(IV) were obtained as 1.7% and 1.87%. The detection limits (7 blanks) for both the metal ions were found to be 1.7 × 10−7 mol dm−3. The important benefit of the method is that the determinations are free from the interference of almost all cations and anions found in the complex matrixes, such as seawater samples. The proposed method was also applied to reference materials, and the determinations were shown to have good agreement with the certified values.

Studies on biodegradation of organic flotation collectors using Bacillus polymyxa

Biodegradation of organic flotation collectors, namely sodium isopropylxanthate, dodecylammonium acetate and sodium oleate in solution, was studied using Bacillus polymyxa. The biodegradation has been assessed under different conditions, namely during growth, in the presence of the cells, metabolite or an active culture. Xanthate biodegradation was found to be better in the presence of an active culture or metabolite, while the biodegradation of dodecylammonium acetate was more efficient during bacterial growth. The efficacy of biodegradation of sodium oleate was the highest using an active culture. The growth of the organism could be successfully achieved in the presence of the organic collectors. The surface chemical changes brought about by the interaction between the minerals, namely galena, quartz or calcite and collector, metabolite or cells served as indicators of the biodegradation process. The biological stripping of the adsorbed collector reagents from mineral surfaces was also confirmed by FTIR spectroscopy.

Investigations on the Collector Reagent Development for the Recovery of Cassiterite from the Gravity Tails of a Low Grade Indian Tin Ore

Results of the experimental studies carried out for developing a flowsheet for the recovery of cassiterite from the gravity tails of a low grade lode type tin ore (Tosham, Haryana) from India by froth flotation using three different collector reagents — alkyl phosphonic acid, sodium sulfosuccinamate and alkyl phosphoric acid ester are presented. The studies include micro-flotation of high purity cassiterite from Tosham, bench scale studies on gravity tails of Tosham tin ore, large scale semi-continuous test with relatively better reagent at optimised flotation conditions ending up with development of conceptual flowsheet meant for obtaining fuming grade cassiterite concentrate. The performance of various collector reagents was analysed on the basis of conventional metallurgical accounting methods and flotation kinetic rate constants. From a feed containing 0.24% Sn, a float product analysing 7% Sn with 55% recovery was obtained using a reagent combination of alkyl phosphoric acid ester-sodium silicofluoride - commercial grade sulfuric acid and citric acid.

Biological removal of some flotation collector reagents from aqueous solutions and mineral surfaces

The utility of Bacillus polymyxa, a heterotrophic bacterium indigenous to ore deposits in the degradation of several flotation collectors has been demonstrated. Dodecyl amine, diamine, isopropyl xanthate and sodium oleate could be efficiently removed from alkaline solutions through bioremediation in an environmentally acceptable fashion. The bacterial cells were also found to be capable of stripping adsorbed collector reagents from various mineral surfaces. Mechanisms of such a biodegradation process are illustrated through results obtained from zeta potential, adsorption, bacterial growth and surface analysis studies.

Evaluation of mitomycin-treated vero cells as a coculture system supportive of the in vitro development of IVM/IVF-derived bovine zygotes to hatched blastocysts

Styrene phosphonic acid (SPA) is one of the best collector reagents for flotation of cassiterite and the best collector for the flotation of finely disseminated cassiterite and wolframite ores. Data from our research work has shown that only with SPA is it possible to obtain higher grade tin concentrates containing more than 40% Sn at high recoveries.The basis for this is the named collector, a highly developed reagent system and a special flotation technology, which was carried out in cyclic Laboratory tests with tin ores from Czechoslovakia, Canada, Portugal and Germany, and introduced into the processing plants at Neves Corvo, Portugal, Rio Kemptville, Canada and Altenberg, Germany.

5358120 Selective separation of finely-divided minerals by addition of selective collector reagent and centrifugation

5358120 Selective separation of finely-divided minerals by addition of selective collector reagent and centrifugation

5358120 Selective separation of finely-divided minerals by addition of selective collector reagent and centrifugation

5358120 Selective separation of finely-divided minerals by addition of selective collector reagent and centrifugation

5358120 Selective separation of finely-divided minerals by addition of selective collector reagent and centrifugation

The effective and representative pore radii (R50) determined from the physical experiments such as capillary penetration and porosimetry were found to be different for porous materials like ceramic and particulate structures. These differences were attributed to contact angle variations, possibly induced by contaminations. In this paper, we studied the relationship between effective and representative pore radii using “numerical experiments”, in which the contact angle variations were eliminated by using a constant contact angle. Micro-scale simulations of capillary penetration of a wetting liquid (air–water configuration) through virtual fibrous media were performed using a finite-volume-based volume-of-fluid (VOF) method. From the simulations, it was found that unidirectional liquid penetration followed Lucas–Washburn kinetics (L∼t) at the micro-scale, except during the initial stages that are dominated by the inertial forces. Even though the contact angle was held constant in the numerical simulations, the effective pore radii of the fibrous structures differed significantly from the representative pore radii (R50). The results suggest that a unique value for the characteristic pore radius does not exist for a porous medium, and the value of characteristic pore radius is strongly dependent on the experimental technique used to characterize the medium. Thus, the choice of experimental technique (e.g. porosimetry or capillary penetration experiment) to determine a characteristic pore radius should be based on the end application of the porous material.

5311997 Selective separation of finely-divided minerals by addition of selective collector reagent and centrifugation: George E Gantt, Thomas J Adkisson, Preston B Gladin, Randall Ussery assigned to Engelhard Corporation

5311997 Selective separation of finely-divided minerals by addition of selective collector reagent and centrifugation: George E Gantt, Thomas J Adkisson, Preston B Gladin, Randall Ussery assigned to Engelhard Corporation

Cassiterite flotation using styrene phosphonic acid to produce high-grade concentrates at high recoveries from finely disseminated ores- comparison with other collectors and discussion of effective circuit configurations

Styrene phosphonic acid (SPA) is one of the best collector reagents for flotation of cassiterite and the best collector for the flotation of finely disseminated cassiterite and wolframite ores. Data from our research work has shown that only with SPA is it possible to obtain higher grade tin concentrates containing more than 40% Sn at high recoveries. The basis for this is the named collector, a highly developed reagent system and a special flotation technology, which was carried out in cyclic Laboratory tests with tin ores from Czechoslovakia, Canada, Portugal and Germany, and introduced into the processing plants at Neves Corvo, Portugal, Rio Kemptville, Canada and Altenberg, Germany.

Studies on chalcopyrite ore grinding with respect to ball wear and effect on flotation

Significance of grinding media wear and its effect on chalcopyrite flotation are discussed. Laboratory marked ball wear tests were conducted grinding chalcopyrite ore and quartzite dry, wet, and with collector added during grinding. The effects of oxygen and nitrogen on ball wear were evaluated by the addition of chalcopyrite mineral while grinding quartzite. The effect of dry and wet grinding on chalcopyrite flotation was also studied. Results show abrasive wear is greater in quartzite grinding than in grinding chalcopyrite. Oxygen increases the corrosive wear of high carbon low alloy steel balls in the presence of chalcopyrite ore. Chalcopyrite flotation was retarded due to wet grinding in the presence of oxygen. Though collector reagent increased the media wear, it improved the flotation of chalcopyrite. Probable electrochemical reactions encountered in a grinding mill are outlined.

Pulp chemistry in calcite flotation. Modelling of oleate adsorption using theoretical equilibrium calculations

The usual method of obtaining calcite concentrates is reverse flotation, i.e. removal of impurities by flotation. This paper considers the conditions required for direct flotation of calcite. The reason is that calcite often occurs as an impurity in apatite and scheelite flotation, where it floats together with the principal mineral. In this context it is relevant to understand the mechanisms that control the flotation of calcite. Flotation experiments have been performed with oleate as the collector reagent and water glass as the dispersant and modifier. To be able to explain what happens in the flotation, solubility and adsorption experiments have been conducted parallel to, and under the same conditions as, the flotation experiments. Theoretical equilibrium calculations have been made with the help of data from the practical experiments for the purpose of modelling the adsorption experiments. The calculations point to the existence of a surface complex, CaOHO1, which is important at pH>10 and low oleate concentrations. Ca(O1) 2 is formed at lower pH. Water glass has a negative effect on oleate adsorption and if the water glass concentration is high enough, >200 g/t, calcite is totally depressed. With theoretical equilibrium calculations it is possible to predict that silicate ions will form complexes with calcium ions at the mineral surface.

Pulp chemistry in industrial mineral flotation. Studies of surface complex on calcite and apatite surfaces using FTIR spectroscopy

Flotation experiments in a Hallimond tube have been performed on calcite and apatite at pH levels and oleate concentrations judged to be interesting from the point of view of adsorption isotherms. For the calcite system adsorption isotherms indicate precipitation of calcium oleate after monolayer formation at pH 9, 10 and 11, whereas in the apatite system a double layer of oleate is formed. This means that apatite, unlike calcite, is sensitive to collector reagent overdosage. With the aid of FTIR techniques it is possible to demonstrate the existence of a surface complex in the apatite system with a calcium-oleate ratio of 1:1 at monolayer coverage of the mineral surface. In conditions corresponding to bulk precipitation of calcium oleate, this compound can be detected by FTIR analysis of unfloated material.

NiS<SUB>4</SUB>型錯体とアミンの付加反応

The stability constants of the adducts formed between squareplanar sulphur-coordinated nickel (II) chelates and N-bases are obtained from spectrophotometric measurements in benzene solution at 25°C.The effects of sulphur coordinating ligands, N-bases and solvents on the stability of the adducts are discussed and those results are applied to the surface reactions between the surfaces of sulfide minerals and collector reagents such as xanthates and aerofloats.