Synthesis Of A New Collector Alkyl Polyamin Ether (Ge-609) And Researcher Of Its Flotation Bhavior Cement

The main characters of China's iron ore resource are poor, fine and complicated. With the exhaustion of iron ore resources, it is increasingly important to utilize resources which are difficult to exploit with the exhaustion of iron ore resources that are easy to be utilized. At the same time, the higher quality of iron concentrate is required by Iron and Steel Plant, thus, in order to increase iron grade, many domestic large-scale mines add the flotation process to separate the silicate from the magnetite. There are mainly two reverse flotation processes currently:one is the anionic reverse flotation process, which is stable and its index is good, the drawbacks are complex reagent varieties as well as higher flotation temperature which requires heating, as a result, the production cost is higher. Another is cationic reverse flotation process; the advantages are a single reagent system, low flotation temperature and good dressing indexes. While the instability process, especially lots of foam run out of bubble cell as there is a large amount of mud in ore, affecting normal production. When fatty amine is used as the collector in cationic reverse flotation process, there is a large amount of viscosity foam, which makes its industrial applications difficult, the aim of this research is to solve this problem. A series of new cationic collectors are synthesized through lots of experimental research, especially introduced ether into molecular structure, makeing the collector's water-soluble as well as the nature of the bubble fundamentally improved, and the crisp foam can be defoamed easily. At the same time, the molecular structure has more than one amine by addition and aggregation methods, which makes its adsorption on the mineral's surface easily; as a result the collector power has been improved. Thus the cationic reverse flotation technology can be successfully applied in separating the silicon from the magnetite.The successful synthesis of a new cationic collector alkyl polyamine ethers is the key step of this paper, based on the experiences of its synthesis and application at domestic or abroad. The synthesis conditions of monoamine alkyl ether are determined through the selection of raw materials, the synthetic experience of process conditions. that is:1, Polymerization reaction, reactant ratio:ROH:CH= CHCN=1:1 (molar ratio), the weight of catalyst:the weight of the reactants 4‰reaction temperature:46±3℃, reaction time:130-140min2, Hydrogenation reaction, the weight of catalyst:the weight of the reactants 3.5%-4%, reaction temperature:140-150℃, stirring speed:850r/min, reaction pressure:2.5-2.8MPa.Alkyl ether polyamine synthetic conditions:1, Polymerization reactions:reaction temperature 48±3℃, reaction time 120-140min2, Hydrogenation reactions:the weight of catalyst:the weight of the reactants=3-3.5‰, reaction temperature:150-160℃, stirring speed:890r/min, reaction pressure:2.5-3MPaOn the basis of the above reaction process conditions, the conversion rate of monoamine ether reaction is greater than 90%, reaction conversion rate of diamine ether is greater than 90% too, a pilot plant scale as well as a industrial scale study of pharmaceutical synthesis were completed successfully, and currently the industrial production of this reagent has been achieved.Since the floatability of different ores is not the same, this paper chooses Jiuquan Iron & Steel Group's roasting magnetite which is difficult to process and from Taiyuan Iron& Steel Group's Jianshan iron ore which is easy to process as the purpose minerals to evaluate the properties of those reagents. The roasting iron ore's surface was passivated by high-temperature calcination, thus, there is basically no separation effect when using conventional anionic collector as the reagent. In this study, alkyl ether polyamine was applied as the collector of reverse flotation to reject gangue minerals such as jasper and quartz, what's more, neutralization experiences of alkyl ether polyamine using acetic acid and hydrochloric acid reveal that organic acid can increase the recovery rate of concentrate. There is no influence of Ca2+, Mg2+ ions on the flotation performance of alkyl ether polyamines, which indicates that it adapts hard water. Batch scale flotation tests, closed-circuit flotation tests and industrial scale flotation tests were conducted, which showed that polyamine alkyl ether is the most suitable and effective reverse flotation collector for Jiuquan Iron& Steel Group's roasting ore.The amount of starch which was used as iron depressant is 600g/t, the amount of alkyl ether polyamines is 180g/t, when the feed grade TFe 54.49%, through one roughing, one cleaning and four scavenging flotation, a good result has been received: the yield is 82.53%, concentrate grade is TFe 62.15%, recovery is 94.13% in tap water,and the yield is 82.42%,grade is TFe61.83%, recovery is 93.47% in hard water. This indicates that alkyl ether polyamines can adapt to the high hardness production water from JISCO.Comparing Alkyl polyamine ether with ARMEEN12D and dodecylamine, according to the flotation of Iron ore from Taiyuan Iron and Steel Group's Jiansan iron mine, the foam amount of alkyl polyamine ether is equivalent to one-third of them, and there is a greater decline in the amount of foam of scavenging flotation, which indicates alkyl ether polyamines can be used as a collector in reverse flotation of iron ore from TISCO Jianshan Iron Mine. A good result was achieved in the experiment of flotation condition and flotation temperature, when the flotation temperatures were 25℃and 8℃,with the feed grade TFe 65.46%, the concentrate grade is TFe 69.22% and TFe 69.17%, and the recovery rate is 97.90% and 97.83% respectively.It can be considered that alkyl ether polyamines have enough collecting power and good selectivity on the flotation of iron ore from Jiansan Iron Mine, and it can be applied at lower flotation temperature. The mine is currently being going to replace the original anionic reverse flotation process with cationic reverse flotation process, thus, the aims of saving energy and reducing production cost can be achieved.Experimental studies have shown that polyamine alkyl ether can also be used as collector in reverse flotation of phosphate rock, which separates the silica and feldspar from phosphate rock. What's more, it can be an effective collector to those minerals such as mica, quartz, salt and zinc oxide. Especially in the study of flotation of low-grade phosphate rock, it can make the content of SiO2 in collophane dropped substantially from 12.82% to 6.18%, making a substantial increase in the grade of phosphate concentrate, and resolving problem that it is difficult to remove silicate minerals by traditional single-anionic flotation.A series of tests were conducted to investigate the separation mechanism of roasting magnetic concentrates and jasper from Jiuquan Iron& Steel Group by alkyl polyamine ethers, and those tests include solution chemical analysis, infrared spectroscopy,ξ-potential testing and so on.The purpose mineral of reverse flotation is jasper, the analysis of its XRD pattern shows that, besides quartz, the main impurities are hematite, siderite, and dolomite. Compared with quartz, the floatability of jasper is closer to the iron minerals, that is, the selectivity of separating jasper and iron minerals by flotation is worse.ξ-potential test also proved that the iso-electric point of quartz is pH2.5, jasper's iso-electric point is pH4.6, while the iso-electric point of magnetite is pH 6.5, compared with quartz, the negative charge on jasper's surface is less obviously, which is not good for the adsorption of cationic collector. So the separation of magnetite and jasper is more difficult.At 4.69, electrostatic adsorption is reduced and collector effect will deteriorate because of a sharp decline in [RNH42+] concentration. When pH> PHs, alkyl polyamine ethers molecules are forming by precipitation, electrostatic adsorption can not be achieve and the collector is ineffective. The infrared spectra of jasper which is adsorbed by alkyl polyamine ethers also show that the reagent's adsorption characteristics peak of Jasper is very clear, which indicates the reagent adsorption on jasper's surface, so Jasper can be hydrophobic and going up, however, magnetite's iso-electric point is pH6.5, In the neutral medium, negative charge on the surface is zero, and positive ion [RNH42+] of the collector can not generate electrical attraction, so its collecting power is poor. As a result, the reverse flotation of jasper can be achieved.Through this research, a new collector is developed successfully which adapted to China's separation of some iron ore and iron-containing silicate by reverse flotation, and it has been successfully applied in industrial production which solves the problem of separating iron and silicate, but it can't adapted to iron ore which contains a large amount of mud, so further investigation of new cationic collector used in reverse flotation, with poor sensitivity to the slime as well as adapt to hematite, is still the way forward.