Synthesis And Flotation Performance Of New Collectors In Reverse Flotation Of Hematite

The resource of iron ores in china is abundant, while with the extended exploitation of mine, the grade of minerals is decreasing year by year. And the separation is more and more difficult. For the ores which are poor and difficult to to exploit, it is difficult to achieve the smelt standard by traditional separation technique such as magnetic. So the status of flotation in iron ores separation is more and more important. The sticking point for successful application of flotation lies on the proper selectivity of flotation regents.Research on flotation reagents in china stays on top, the regenerative speed is fast. And many reagents have been used in industry. While, there are still many deficiencies in development of reverse flotation reagents of iron ores. For example, the complexicity of operate condition on anion collectors or the low of flotation efficiency on cation collectors. So, strengthening the investigation of new and high-efficiency hematite collectors used for reverse flotation is significant in enhancing the complex utilization of iron ores in china.In this paper, the reverse flotation circumstances of hematite separation is analized, and two collectors (which are N-laurel-1,3-diaminopropanes and N-laurel ethanediamine) is designed. And collect capabilities of the two collectors are discussed by flotation experiment of single minerals, flotation experiment of manual mixture minerals and flotation experiment of factual ores. The structure-flotation relation is discussed and collect mechanism is analysized by the measurement of contact angle, Z-potentials, XPS and FT-IR spectrum. The research work incarnates concretely in the following aspects.(1) N-laurel-1,3-diaminopropanes is synthesized by addition reaction and reductive amination reaction using fat amine and acryloritrile as reactants without catalystas; and N-laurel ethanediamine is synthesized by halogenated hydrocarbons ammonolysis process using 1-bromododecane and ethylenediamine as reactants when rthanol is used as solvent. And the two products are represented FT-IR sprectrum, MIR techniques, melting point measurement and element analysis.(2) The flotation abilities of N-laurel-1,3-diaminopropanes and N-laurel ethanediamine to hematite and quartz are researched by single mineral flotation. And the flotation performance is compared with traditional cation collectors, which is dodecylamine. From th results, it can be seen that when collector concentration is 50.0mg/L, pH is 10.08 and using N-laurel-1,3-diaminopropanes as collector, the recovery of quartz achieve its maximum, which is 98.39%; while the collector concentration is 41.7mg/L、pH is 6.6 using N-laurel ethanediamine as collector, the recovery of quartz achieve its maximum, which is 98.10%. And collect capabilities of the two collectors to hematite are very poor. When N-laurel-1,3-diaminopropanes is used as collector, the maximum recovery of hematite is less than 80%, while less than 50% when N-laurel ethanediamine used.(3) Mixed hematite and quartz minerals according to the quality ratios which are 2:3,5:5 and 3:2 to make up manual mixture minerals. And separation results of the two collectors to manual mixture minerals are probed into. The results show that the two collectors have better separation capabilities to the mixture.(4) The flotation-structure reactions of the two collectors are discussed by measuring the electronegativity, radical size, flotation idiocratic index, HLB and distribute coefficient. From the calculation it can be seen that the two collectors are fit for oxide minerals flotation. And they have better flotation activities, selectivities and mineral surface adhersive capabilities.(5) Flotation mechanism of the two collectors to quartz is discussed by measurements of contact angle, Z-potientials, XPS and FT-IR spectrum. And electrostatic attraction and hydrogen bond is occurred between flotation regents and mineral surface.(6) Practical ore flotation test is performed to confirm the separation capabilities of the two collectors to practical iron ores. By remill experiments, when the granularity of ore is-0.074mm 98.63%, favourable effects which grade is 67.20% and revovery is 77.8% are acquired when N-laurel ethanediamine is used as collector, while grade is 66.78% and revovery is 75.71% when N-laurel-1,3-diaminopropanes is used. Compared with dodecylamine, the two new collectors have stronger collectivity to irons.(7) The bubble performances of the two new collectors are discussed by measurnent of resudial foams. From the results, it can be seen that the new collectors has better defoam performance than dodecylamine.