Effect Of Modified Kerosene On Slime Flotation Performance By Electrochemical

Coal processing is one of the most effective method,which can improve the effective utilization of coal energy,enhance the quality of commercial coal,cut down the invalid transportation,reduce the pollution of environment and increase the economic benefit of coal companies.With increasing of the amount of slime in coal preparation plant,the flotation become the most effective sorting method of coal slime and the most significant method to improve the efficiency.the collector plays a decisive role in flotation process and the widely used collector is kerosene in the coal preparation plant,but the low collecting material content in common kerosene leads to poor floatation effect.Therefore,to improve the collecting performance by modifying kerosene becomes a problem urgently to be solved.This paper used kerosene as raw material.Firstly,emulsified kerosene was catalytic oxidized by electrochemical.And based on the FTIR analysis results of the sample before and after the oxidation,the mechanism of oxidation and catalysis was initially explored.Finanlly,The flotation verification test was carried out on slime of coal.The following conclusions were drawn:1.Based on the industrial analysis,XRD and particle size distribution,we can see montmorillonite in coal will swelling in water and the flotation effect was seriously deteriorated.The content of<0.045mm is 21.76%and it's ash content is 35.28%.Ma Lan 02#is medium floatability coal through the distribution of release test.2.Kerosene was emulsified by 25kHz ultrasonic.The optimum conditions are:oil:water is 1:4,ultrasonic time is 2min,ultrasound intensity is 0.6250W/cm3,probe diameter is 8mm.Contact angle is 85.426° of emulsified kerosene in coal particle under this experiment condition,and its average particle size is 8.41 ?m,stabilization time>2h,layer height is Ocm.3.The effect of catalytic oxidation was investigated on acid value,density of kerosene,contact angle by electrochemical.The best acid value is 7.38mgKOH/g,which were obtained in the conditons:electrolysis time is 40min,the amount of potassium permanganate is 500mg/l,electrolytic current density is 2000 A/m2,sulfuric acid is 8%as electrolyte,the best electrodes are graphite-stainless steel,but it is 0.20 mgKOH/g without modifying by oxidation of kerosene.And the contact angle of water and coal was increased from 75.964° to 82.030° by treated oxidation kerosene.That's show that the coal samples hydrophobicity enhanced by the treated oxidation kerosene,also the kerosene collect performance improved after the oxidation.4.FTIR results shown that,some carbonyl compounds were mainly generated by oxidation in kerosene.The carboxylic acids can collect coal partical and ketones,aldehydes substance can generat bubbles,which can improve the effect of oxidation kerosene for flotation.In addition,ethers,esters and part of alcohols was also produced in oxidation kerosene,these substances can play a dilution effect on promote the kerosene with collecting material.5.The flotation test results of coal shown that:under the near condition of ash content and yield in clean coal,the collector consumption reduced 25%and the frother reduced 50%than using ordinary kerosene as collector when using the acid number for 5.47mgKOH/g oxidation kerosene as collector;the collector consumption reduced 50%and the frother reduced 50%when using the acid number for 7.42mgKOH/g oxidation kerosene as collector.