摘要
以油酸钠为捕收剂,考察了搅拌预处理引起的铝离子溶出对微细粒一水硬铝石浮选行为的影响。浮选结果表明:添加少量铝离子能促进矿物浮选,添加铝离子浓度大于1×10^(-5)mol/L后,矿物可浮性逐渐降低;短时间搅拌预处理可提高浮选回收率,搅拌时间大于10 min后,浮选效果逐渐变差。ICP、吸附量、接触角测定结果和浮选溶液化学分析表明:铝离子添加量较小时,溶液中铝离子主要形成羟基络合物,促进油酸钠吸附,增强矿物疏水性;铝离子添加量较大时,亲水性氢氧化物沉淀逐渐增多,矿物疏水性变差,可浮性降低。Zeta电位和粒度测试结果表明:搅拌预处理后,颗粒表面负电性降低、粒度变粗,这说明颗粒形成絮团。适宜条件下搅拌预处理有助于絮团生长,这也是搅拌预处理相比于直接添加铝离子能够获得更高浮选回收率的重要原因。
The objective of this study was to assess the effect of Al3+dissolution induced by pre-agitation on the flotation of ultra-fine diaspore with the addition of NaOl. The results of flotation tests show that the addition of a small amount of Al3+into the pulp is helpful for flotation, however, after Al3+concentration is higher than 1×10-5 mol/L, the addition of Al3+has a detrimental effect on flotation. A short time of pre-agitation can improve the recovery of diaspore, while the recovery decreases gradually when the miners are agitated more than 10 min. ICP measurements, adsorption capacity measurements, contact angle measurements and the analysis results of flotation solution chemistry show that Al3+exists mainly as a form of hydroxy complexes in solution with a small additive quantity, which promotes the adsorption of NaOl on the mineral surface and enhances the hydrophobicity of diaspore. With a big additive quantity, the amount of hydrophilic hydroxide precipitation increases gradually, and the hydrophobicity of minerals becomes worse so that the floatability is decreased. Zeta potential measurements and particle size measurements show that the electronegativity of particles decreases and the particle size increases after pre-agitation, the results indicate the formation of flocculation.Compared with the direct addition of Al3+, an appropriate pre-agitation is beneficial to the formation of hydrophobic flocculation in pre-agitation, which is also an important reason for the higher recovery.
作者
朱仔成
欧乐明
周伟光
ZHU Zi-cheng;OU Le-ming;ZHOU Wei-guang(School of Minerals Processing and Bioengineering,Central South University,Changsha 410083,China)
出处
《中国有色金属学报》
EI
CAS
CSCD
北大核心
2019年第2期415-421,共7页
The Chinese Journal of Nonferrous Metals
基金
国家重点基础研究发展规划资助项目(2014CB643402)
国家自然科学基金资助项目(51674291)
战略金属矿产资源清洁高效利用协同创新中心(湖南省2011计划)资助项目~~
关键词
搅拌预处理
一水硬铝石
微细粒浮选
离子溶出
疏水聚团
pre-agitation
diaspore
ultra-fine particle flotation
ions dissolution
hydrophobic flocculation
