| As an important raw materials for phosphorus chemical industry,phosphate ore reserves of China is extremely rich.However,with the sharp increase in demand for phosphorus,the mining of phosphate ore is excessive,and as a result,the high-grade collophane is becoming less than before,the low-grade cellophane is more and more,so the development and utilization of low and medium grade cellophane is the key.The traditional flotation collector of fatty acid has some disadvantages,such as the poor water solubility at room temperature,the poor performance of selectivity and decentralization.In order to solve the problem,this article proposed a novel steps of modified stearic acid,including the chlorination,hydroxylation,sulfonation and amination.With the introduction of selective functional groups,some new types of negative ion phosphate flotation collector of α-chloro stearic acid,α-hydroxy stearic acid,α-sulfonated stearic acid and a new type of amphoteric phosphate flotation collector of α-amino stearic acid were synthesized,also,a series of flotation collector of FH were obtained by compounding with other fatty acid and sodium hydroxide.In order to study how well the series of collector FH work on the phosphate flotation,the collector FH-2,FH-3 and FH-5 were applied to the coarse flotation experiment of a certain calcium collophanite from Yichang and the collector FH-1 and FH-4 were applied to the flotation experiment of a certain siliceous collophanite from Longmang,of which the indicators of beneficiation were excellent.The flotation process experiments showed that both α-hydroxy stearic acid and α-sulfonated stearic acid have capability of flotation with calcium-magnesium gangue mineral and that α-chloro stearic acid can be used as a good flotation collector which has the ability of flotation with silicate gangue mineral,although the performance of α-amino stearic acid in the test was not very good when compared with the other collectors,it can be used as positive flotation collector as well as reverse flotation collector and also has good solubility in water even under low temperature conditions.Micro flotation experiments of pure minerals,Zeta potential measurement andinfrared spectroscopy were carried out to identify the flotation process and clarify the interaction mechanism of collectors and the three pure minerals which including apatite,dolomite and quartz.The study showed that collector α-hydroxy stearic acid,α-sulfonated stearic acid and α-amino stearic acid have good absorption on the surface of dolomite and the collector α-chloro stearic acid and α-amino stearic acid have high absorption capacity on the surface of apatite,while the experimental study of the mechanism proves that all these flotation collectors can absorb on the surface of minerals selectively and the mineral surface physical properties will be changed as well as the mineral flotability. |
