低阶煤颗粒-气/油泡间的疏水力常数研究  

Investigation of hydrophobicity constants between air/oily bubbles and low-rank coal particles

作　　者：王市委 陈松降[2] 陶秀祥 石开仪[1] 陈鹏 陈文辉 WANG Shiwei;CHEN Songjiang;TAO Xiuxiang;SHI Kaiyi;CHEN Peng;CHEN Wenhui(School of Chemistry and Materials Engineering,Liupanshui Normal University,Liupanshui 553000,China;School of Chemical Engineering and Technology,China University of Mining and Technology,Xuzhou 221116,China)

机构地区：[1]六盘水师范学院化学与材料工程学院,贵州六盘水553000 [2]中国矿业大学化工学院,江苏徐州221116

出　　处：《煤炭学报》2019年第7期2236-2244,共9页Journal of China Coal Society

基　　金：国家自然科学基金资助项目(51774284);六盘水师范学院校级基金资助项目(LPSSYKYJJ201811);贵州省科技厅科技平台及人才团队计划资助项目(黔科合平台人才[2017]5721)

摘　　要：浮选实验表明油泡对低阶煤颗粒的捕收能力要远强于传统浮选过程的起泡。这主要是由于油泡表面被捕收剂覆盖,其表面疏水性要远高于气泡表面的疏水性。因此,在油泡浮选矿化过程中,低阶煤颗粒-油泡间水化膜的薄化速度要远快于煤颗粒-气泡间的薄化速度。诱导时间测试发现,随着DAH溶液浓度从10-7mol/L增加到5×10-5mol/L时,低阶煤颗粒-气泡间的诱导时间从93ms下降到12ms。随着DAH溶液浓度从5×10-5mol/L增加到10-3mol/L时,低阶煤颗粒-气泡间的诱导时间从12ms增加到35ms。当DAH浓度由10-7mol/L(纯去离子水溶液)增加到5×10-5mol/L,低阶煤颗粒-油泡间的诱导时间由35ms降低到10ms。随着DAH浓度的进一步增加到10-3mol/L时,低阶煤颗粒-油泡间的诱导时间由10ms增加到25ms。为了从微观尺度下去表征油泡表面较气泡表面所具有的强疏水性,本文通过低阶煤颗粒-油/气泡间的诱导时间,利用non-DLVO理论及Stefan-Reynolds水化膜薄化模型,拟合出初始水化膜厚度h与疏水性常数K132之间的关系,进而得到了低阶煤颗粒-油/气泡间的疏水力常数K132与十二烷胺盐酸盐DAH溶液浓度的关系。疏水力常数K132拟合结果表明,当DAH溶液的浓度为5×10-5mol/L时,低阶煤颗粒-油泡间的疏水力常数K132约为低阶煤颗粒-气泡间的疏水力常数K132的3倍;当DAH溶液的浓度为10-6mol/L时,前者是后者的15倍。因此,油泡表面较气泡具有更强的疏水性质。从而解释了低阶煤-油泡浮选矿化过程优于传统浮选过程的本质特征。Flotation results showed that the ability of oily bubbles to collect low-rank coal particles is much stronger than that of air bubble in traditional flotation processes.It is because the surface of the oily bubble is covered by the collector,and its surface is much more hydrophobic than the surface of the air bubble.Therefore,in the interaction process of low-rank coal particle-oily bubble,the thinning speed of hydration film is much faster than that of low-rank coal particle-air bubble.The results of induction time test indicated that the induction time between low-rank coal particles and air bubbles decreased from 93 ms to12 ms as the concentration of DAH solution increased from10 -7 mol/L to 5×10 -5 mol/L.As the concentration of DAH solution increased from 5×10 -5 mol/L to10 -3 mol/L,the induction time between low-rank coal particles and air bubbles increased from12 ms to 35 ms.The induction time between low-rank coal particles and oily bubbles decreased from 35 ms to10 ms while the DAH concentration was increased from10 -7 mol/L (pure deionized water solution) to 5×10 -5 mol/L.As the DAH concentration increased to10 -3 mol/L,the induction time between low-rank coal particles and oily bubbles increased from10 ms to25 ms.In order to compare the strong surface hydrophobicity of the oily bubble with the surface hydrophobicity of the bubble from the microscopic scale,the non-DLVO theory and the Stefan-Reynolds hydration film thinning model were adopted.Based on the induction time results of low-rank coal particles-oily/bubble,the relationship between the initial hydration film thickness ( h ) and the hydrophobicity constant ( K132 ) was fitted.Moreover,the relationship between the hydrophobic force constant ( K132 ) and the concentrations of the DAH solution was obtained.The fitting results of hydrophobic force constant ( K132 ) showed that the hydrophobic force constant ( K132 ) between low-rank coal particles and oily bubbles was three times than that between low- rank coal particles and air bubbles while the

关 键 词：低阶煤 疏水力常数 水化膜 油泡 诱导时间 non-DLVO理论 

分 类 号：TD923[矿业工程—选矿] TD94