低温空气等离子体对石英表面性质的影响  

Modification of quartz in a low-temperature air plasma

作　　者：王大鹏[1] 胥萌 晋伟 王波 闫小康[1] 

机构地区：[1]中国矿业大学化工学院,江苏徐州221116 [2]国家煤加工与洁净化工程技术研究中心,江苏徐州221116

出　　处：《煤炭学报》2017年第10期2752-2757,共6页Journal of China Coal Society

基　　金："十二五"国家科技支撑计划资助项目(2014BAB01B02);国家自然科学基金资助项目(51704290);江苏省自然科学基金资助项目(BK20170285)

摘　　要：为增加石英与褐煤的可浮性差异,提出了采用低温空气等离子体改性的思路。采用扫描电镜(SEM)、能谱分析(EDS)、X射线光电子能谱分析(XPS)、接触角、浮选试验研究了等离子体处理对石英表面性质、可浮性的影响。SEM结果显示改性后表面形貌变化不大,新生了1~5μm的硅酸盐矿物颗粒;XPS分析表明C—C/C—H含量逐渐降低,C—O含量逐渐增大,C O,COO含量基本不变;接触角及浮选试验结果表明处理1~5 min石英与褐煤接触角差值增大了2.5~3.2倍。单独浮选时处理后石英浮出率基本不变,褐煤浮出率显著降低。混合浮选时,采用等离子体预处理获得了精煤灰分8.32%、产率37.8%的良好指标。等离子体改性显著扩大了石英与褐煤可浮性差异,利用其抑制褐煤反浮选石英是可行的。In this study,the feasibility of quartz reverse flotation by depressing lignite using low-temperature air plasma pre-treatment was investigated. SEM,EDS,XPS and contact angle were carried out to measure the surface property of pure quartz before and after plasma treatment. SEM detected the new product of 1-5 μm metal silicate mineral grains on the quartz surface after plasma treatment,but the surface change was little. XPS results show that the content of C—C/C—H groups decreased gradually,and the content of C—O group increased. However,the contents of C O and COO groups did not change. The contact angle and flotation test results indicate that the difference of contact angle between quartz and lignite treated for 1-5 minutes increased by 2. 5-3. 2 times. The rate of quartz floatation was almost constant when treated with flotation alone,and the rate of lignite was significantly reduced. At the time of mixed flotation,the plasma pretreatment was used to obtain the good index of 8. 32% of concentrate ash and 37. 8% of yield. The plasma modification significantly expanded the difference between quartz and lignite,and it was feasible to inhibit the reverse flotation of lignite.

关 键 词：低温等离子体 石英 褐煤 表面性质 

分 类 号：TD923.4[矿业工程—选矿]