Mechanism of action of scheelite collector

Zhang Qingpeng et al. studied the capture performance of different structural fatty acid collectors for scheelite. Studies have shown that the greater the degree of unsaturation of unsaturated fatty acids, the better the flotation effect; when the number of carbon atoms in fatty acid carbon chains is within a certain range, the effect of flotation of scheelite is enhanced with the increase of the number of carbon atoms; carbon chain Heterogeneous hydrocarbon chain unsaturated fatty acids are more effective than normal hydrocarbon chain unsaturated fatty acid flotation scheelite; when fatty acid molecules are introduced into hydroxyl groups, the flotation effect is not as good as that of fatty acids without hydroxyl groups. The adsorption capacity of saturated fatty acids with different carbon numbers on the surface of scheelite is from small to large: lauric acid, myristic acid, palmitic acid, stearic acid; adsorption of unsaturated fatty acids with different double bonds on the surface of scheelite The order of small to large is: linoleic acid, oleic acid, linolenic acid; the carbon chain normal fatty acid monostearic acid adsorbs on the surface of scheelite is smaller than that of carbon chain isomerized isostearic acid; However, stearic acid which also contains no hydrocarbon group adsorbs more on the surface of scheelite than the fatty acid ricinoleic acid which contains a hydroxyl group.

Jiang Qingmei studied the capture performance of sodium oleate, different hydrocarbon fatty acids, sodium oleate and different hydrocarbyl fatty acid combinations on scheelite, fluorite , calcite , and added water glass to reveal the presence of inhibitors in combination with minerals. Differences in harvesting capacity. The results show that the combination of sodium oleate and different hydrocarbyl fatty acids has better effect than single use and strong capture ability. After the addition of the water glass inhibitor, the combination agent has significant difference in the floatability of scheelite with fluorite and calcite. The contact angle test showed that the contact angle of different hydrocarbon-based fatty acid sodium to minerals was different. After mixing, the contact angle of scheelite and fluorite increased more. After adding water glass, the contact angle of scheelite did not change much. The contact angle of fluorite and calcite is significantly reduced, which increases the contact angle difference between scheelite and fluorite and calcite. The results of potentiodynamic test showed that after adding water glass, the combined collector was selectively adsorbed on the surface of scheelite and less adsorbed on the surface of fluorite and calcite. The surface tension test results show that, under the same pH condition, if the same recovery rate is reached, the amount of the combined agent is lower than that of the single agent. The chemical and thermodynamic calculation results of flotation solution show that the mechanism of action of sodium oleate and scheelite, fluorite and calcite is the same, which makes it difficult to separate minerals; the standard freedom of reaction between different hydrocarbon-based fatty acid sodium and mineral lattice cation Ca2+ ions There can be differences, and there are differences in the ability to capture minerals.

Yang Yaohui studied the mixing effect of fatty acid collectors in the flotation process of scheelite. The results of potentiometric titration test showed that the adsorption amount of saturated fatty acid on the surface of scheelite was: stearic acid>palmitic acid>myristic acid>lauric acid; the adsorption amount of unsaturated fatty acid on scheelite surface was: Linolenic acid>oleic acid>linoleic acid; the amount of branched fatty acid-isostearic acid adsorbed on the surface of scheelite is larger than that of stearic acid; the adsorption of hydroxy fatty acid on the surface of scheelite is better than that of stearic acid. Smaller. The results of thermodynamics and flotation solution chemical calculations show that there are differences between â–³G0 (standard free energy) of fatty acids with different structures and calcium silicate mineral lattice cations, which may be the reason for their differences in mineral collection capacity; The fatty acid of different structures is basically the same as that of scheelite, fluorite and calcite in neutral or weakly alkaline medium. After adding calcium ions, there are differences in the concentration of fatty acid calcium formed by different structures. This may be The reason for the difference in mineral harvesting capacity.

Feng Bo studied the flotation behavior of flotation separation of scheelite from calcite using sodium oleate as a collector and sodium silicate as an inhibitor. The results show that sodium oleate has the ability to capture scheelite and calcite. The flotation separation of scheelite and calcite can not be achieved by sodium oleate alone. The inhibitor sodium silicate selectively acts on the surface of the calcite, and the optimum ratio of sodium silicate to oxalic acid is 3:1. The use of sodium silicate as an inhibitor allows the separation of scheelite and calcite. Infrared and potentiodynamic measurements show that pre-adsorption of sodium silicate interferes with the adsorption of sodium oleate on the calcite surface without interfering with its adsorption on the scheelite surface.

Ting System Gold, and combinations of a single collector collecting capability white tungsten ore, fluorite and calcite, results show that: in the absence of added adjusting agent, sodium oleate, oxidized paraffin soap and GYW 731 scheelite, The collection ability of fluorite and calcite is similar and cannot be separated. The combination of sodium oleate and 731 has strong ability to capture scheelite and calcite, and the ability to capture fluorite is weak. Sodium oleate and GYW ​​are combined with scheelite. The difference in the ability of fluorite and calcite to collect is small; the order of collection of 731 and GYW ​​is fluorite > calcite > scheelite > quartz ; the order of combination of collectors for scheelite is: oleic acid Sodium+731>sodium oleate+GYW>731+GYW; the order of combined harvesting ability of fluorite is: 731+GYW>sodium oleate+GYW>sodium oleate+731; combination collector The order of capture ability of calcite is: sodium oleate + 731 > sodium oleate + GYW > 731 + GYW. The collection performance of quartz by single collector and combination of three collectors is weak, indicating that flotation separation of quartz and scheelite is easier.

Hu Hongxi investigated the effects of sodium oleate, 731, 733, TAB-3, TA-3 five fatty acid collectors on the flotation behavior of white tungsten and fluorite, calcite and quartz through a single mineral experiment. At the same time, the order of the floatability of the four single minerals from high to low is: fluorite > calcite > scheelite > quartz. In the high alkali (pH=11.0), high water glass dosage system, when the new scheelite collector TAB-3 is used, the floatability of scheelite and fluorite, scheelite and calcite is significantly different, TAB- 3 shows better selective collection ability, which is beneficial to the effective separation of scheelite-fluorite-calcite scheelite; quartz with TAB-3 in low alkali (pH=8.5) and low water glass dosage system The difference in floatability from scheelite is large, and TAB-3 shows better selective recovery ability, which is beneficial to the effective separation of scheelite-quartz type scheelite. The results of potentiodynamic and infrared spectroscopy indicate that the water glass on the surface of scheelite is adsorbed in the form of associative hydrocarbon groups. TAB-3 still has strong chemical adsorption on the surface of scheelite; water glass is SiO32- and SiO32 on the surface of fluorite. - Form, calcite is strongly adsorbed in the form of SiO32-, TAB-3 is weakly adsorbed in fluorite and calcite, and the difference in adsorption form and adsorption strength of water glass on scheelite, fluorite and calcite surface makes the floatability between minerals The difference is increased.

Zhiyong Gao research uses 733 and MES (fatty acid sodium methyl sulfonate) mixed collector to separate flotation scheelite from calcite and fluorite. 733: MES mass ratio is 4:1, which is better. Selective. Under the condition that the grade of WO3 is only 0.57%, the index of WO3 grade in concentrate is 65.76% and the recovery rate is 66.04%. The presence of Ca2+ or Mg2+ has little effect on the adsorption of mixed collector on the surface of scheelite. The addition of water glass inhibits calcite and fluorite, and has no obvious effect on the adsorption of mixed collector on the surface of scheelite.

ZL collector is a mixture of long carbon hydroxy acid saponification. Ni Zhangyuan et al. studied the flotation behavior of scheelite, fluorite and calcite under the action of ZL collector by single mineral test, potentiodynamic and infrared spectroscopy. And the mechanism of action of ZL collector and calcium-containing minerals. When the amount of sodium silicate is high, ZL collector can effectively separate scheelite from fluorite and calcite under alkaline conditions of pH=11.0. The potentiodynamic and infrared spectroscopy analysis showed that the ZL collector was chemisorbed on the surface of scheelite and calcite and physically adsorbed on the surface of fluorite.

Li Shiliang studied the separation of scheelite and calcium-containing gangue minerals by cation collector flotation. The study shows that under alkaline conditions, as the length of the hydrocarbon chain increases, the alkyl primary amine salt to scheelite, calcite and fluorite The collection capacity of calcium-containing minerals is weakened, that is, dodecylamine>tetradecylamine>octadecylamine. Under acidic conditions, the floatability of scheelite with calcite and fluorite is quite different. The use of alkyl primary amine salt as collector has the possibility of separating scheelite from calcite and fluorite, but the concentration of the agent cannot be Too big. The chemical analysis of the solution shows that the alkyl primary amine salt has an ion molecule dissociation equilibrium in the aqueous solution. When the pH value rises to a certain value, the amine molecule precipitates. At a certain concentration, the different carbon chain alkyl groups form an amine molecule precipitated. The pH value is different. As the number of carbon atoms in the alkyl chain increases, the pH of the precipitate of the amine molecule decreases. The amine ion and the amine molecule can form an ionic molecular association, and the amine ion can form an associate. . The quaternary ammonium salt is completely ionized under the entire pH condition. Zeta potential analysis and adsorption measurement of mineral surface show that the role of quaternary ammonium salt and mineral surface is mainly electrostatic, and there are some adsorption caused by dispersive force, hydrophobicity and hydrogen bonding. The calculation results of HLB value and CMC value show that the CMC value and HLB value decrease with the increase of carbon chain length in the homologue, and the hydrophobicity of the agent increases, but the solubility decreases, which also affects the dissolution and dispersion properties.

Yang Fan et al studied dioctyl dimethyl ammonium bromide (DDAB) scheelite, calcite flotation separation tests showed, DDAB white tungsten ore recovery at a pH> maintained at almost 100% 6, while The recovery rate of calcite is slowly increasing. DDAB can effectively separate scheelite and calcite at pH=8~10. At the same time, the comparison test with oleic acid shows that DDAB has better collection ability and selectivity for scheelite than oleic acid. Infrared spectroscopy analysis of single minerals indicates that there is a major physical interaction between DDAB and minerals. Through the analysis of the molecular structure of DDAB and the relationship between the kinetic potential and pH value of scheelite and calcite in pure water and the pH range of DDAB for flotation of scheelite and calcite, it is concluded that DDAB mainly passes electrostatic force and scheelite surface. effect. Quantum chemical calculations of DDAB and scheelite also directly confirm this inference.

Zhiyong Gao studied the adsorption behavior of dodecylamine on the surface of scheelite and calcite minerals by molecular dynamics simulation, potentiodynamics measurement, atomic force microscopy, contact angle measurement and flotation test. The results show that the different adsorption behaviors of dodecylamine on the surface of scheelite and calcite are mainly attributed to the complexity of cation RNH3+ in the aqueous solution of dodecylamine, neutral substance RNH2 and the reaction of RHEN3+ with the anions released from the surface of the two minerals. Precipitates also play an important role. In the dodecylamine solution (1×10-4 mol/L, pH 7.5-8.0), hydrogen bond adsorption of RNH2 in a large amount of dodecylamine through N-Ca bond and -NH2 group and mineral surface oxygen On the surface of scheelite and calcite. On the surface of a positively charged calcite, RNH3+ is adsorbed in the CO32-region by electrostatic adsorption and hydrogen bonding, which leads to an increase in the surface potential of the calcite surface. On the surface of the negatively charged scheelite, a large amount of cation RNH3+ can be easily adsorbed on a large number of WO42-regions, which leads to a significant increase in the surface potential of the scheelite. These different adsorption behaviors result in the formation of a single layer of dodecylamine on the surface of the scheelite, resulting in a better hydrophobic surface of the scheelite and higher flotation recovery.

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