Study On The Synthesis And Flotation Performance Of New Kind Of Collector Citric Acid Ester Carboxylic Acid

For the better dispose of low and medium grade refractory collophanite in Qingping region of Sichuan province,experiment about reagent development were implemented in this thesis with the view of obtain a new kind of favorable performance positive flotation collector.Through the modification of cotton oil fatty acid with the method of chemical synthesis,citric acid ester carboxylic acid,a novel composite fatty acid anionic collector has been synthesized and used in collophanite flotation.Flotation properties of Qingping collophanite in Sichuan province were studied and determined the appropriate grinding fineness is-0.074 mm about 91.6%.A series of single positive flotation tests were carried out to study the influence of pharmaceutical synthesis way,ratio of materials,synthesis time and reaction temperature on the flotation performance of new collector preliminary evaluated by flotation index.The synthesis method is: the mass ratio of citric acid,n-decyl alcohol or fusel alcohol,cotton oil fatty acid soap is 0.75:1:1.75,solid citric acid and liquid n-decyl alcohol or fusel alcohol first join in the reactor,control temperature at 120-140 centigrade and react for 1h,get yellow transparent homogeneous liquid,add solid cotton oil fatty acid soap and stir well to character change.The mixed product directly used as a flotation collector on collophanite without purified or saponification process.With synthetic drug as direct flotation collector,at the grinding fineness of-0.074 mm content 91.6%,flotation temperature control in twenty centigrade,under reagent regime of roughing sodium carbonate dosage of 6.0 kg/t,sodium silicate dosage of 2.5 kg/t,collector NCM-1 dosage of 0.6 kg/t,concentration without reagent,scavenging add NCM-1 dosage of 0.1kg/t,reverse roughing sulfuric acid dosage of 9.0 kg/t,citric acid dosage of 0.9 kg/t and collector OY-68 dosage of 0.3kg/t,scavenging sulfuric acid dosage of 2.0 kg/t,gain a concentrate P₂O₅ grade of 31.58%,MgO content of 0.79%,recovery of 66.23% for the flotation index through open process test,obtain a concentrate P₂O₅ grade of 30.51%,MgO content of 0.93%,recovery of 64.02% flotation index through closed-circuit test with the ore grade of 22.15%.NCM-2 was produced in the same way as NCM-1 but alternate n-decyl alcohol with fusel alcohol.At the same driect flotation reagent regime as NCM-1,regulate reverse roughing sulfuric acid dosage of 12.0 kg/t,citric acid dosage of 0.9 kg/t and collector OY-68 dosage of 0.6kg/t,scavenging sulfuric acid dosage of 2.0 kg/t,through closed circuit test gain a concentrate grade of 30.03%,recovery of 87.06% for the flotation index.It proved that synthetic reagent NCM-1 and NCM-2 have similar flotation characters and meet the industry standard for phosphate ore production,indicated that the reagent synthesis has certain stability and industurial feasibility.Infrared spectrum analysis showed that the synthesized reagent has functional groups of carboxyl,hydroxyl and ester.Hydrophilic group of hydroxyl and ester increased water solubility of collector.Synthetic modification made cotton oil fatty acid formation a long carbon chain structure of ester carboxylic acid,and the main product is binary carboxylic acid,which increased hydrophobic,collectivity and selectivity.Surface tension test,zeta potential test,infrared spectrum analysis and single mineral flotation test showed that the mechanism of the synthetic reagent is acting on the mineral surface by chemical adsorption and physical adsorption.Through changing the mineral surface electrical,reducing mineral dynamic potential to weaken hydration and increace flotability.By reducing the surface tension of the solution system,the mineral surface get more hydrophobic and floatable.The strong-to-weak sequence of synthetic reagent adsorption ability on single mineral is collophane > dolomite > quartz.Synthetic reagent showed selective adsorption and best flotability on collophane surfaces,for quartz almost don’t float,thus suitable for desilicationn in the positive flotation.With the advantage of excellent water-solubility,stronger collectivity and better selectivity,low temperature resistance,smaller reagent dosage needs,wide raw material sources and low price cost,the synthesized reagent has grate significance on cut flotation cost and enhance recovery with a broad application prospect.