摘要
白钨矿是国家战略性矿产资源。浮选是基于不同矿物表面物理化学性质的差异实现不同矿物之间彼此分离的方法,也是目前高效处理利用白钨矿的最主要方法。基于白钨矿的晶体(表面)结构,研究并总结了表面断裂键性质、解理及暴露面性质、表面(自由)能、润湿性、表面电性、吸附性等白钨矿的表面物理化学性质及其各向异性,归纳了晶体结构特征与表面性质之间的关系,分析了不同表面性质之间的关联,解释了白钨矿的分选原理。研究发现,表面断裂键密度(D_(b))和表面能存在正相关性,(112)、(001)和(101)面是白钨矿最主要的暴露面,具有较小的D_(b)和表面能,其D_(b)大小关系为:(101)面>(112)面>(001)面,所以自然条件下(112)面和(001)面为主要解理和暴露面,(101)面则需要较大外力才能解理。D_(b)越大,矿物亲水性越强,(112)面亲水性比(001)面更强。表面活性氧和钙质点及其断裂键差异可解释表面电性及吸附性的各向异性。表面Ca质点断裂键数多,反应活性高,与药剂结合能高且构型稳定,(001)面具有更高活性氧原子密度,可能通过氢键作用结合更多的OH^(-),导致更高的负表面电势。通过优化磨矿过程中的影响参数,可调控颗粒的高活性晶面暴露情况及颗粒形貌,暴露高活性的(101)面和(112)面,减少(001)面的暴露比例,强化白钨矿的浮选行为。研究结果对于强化白钨矿的浮选分离回收具有重要的指导价值。
Scheelite,a national strategic mineral,is enriched by froth flotation basing on the different physical and chemical properties among scheelite and other gangue minerals.Moreover,flotation is the main method for the efficient recovery of scheelite.Based on the crystal structures of scheelite,the physical and chemical properties and its anisotropy of scheelite such as surface broken bond,cleavage and exposed surface,surface energy,wettability,surface electrokinetic and adsorption properties were studied and summarized.The relationships between different surface properties,as well as with crystal structures were deeply classified.And the separation mechanism of scheelite was explained.Surface broken bond density(D_(b))was positively correlated with surface energy.(112),(001)and(101)are main exposed surfaces of scheelite with smaller D_(b)and surface energy.The values of D_(b)of different scheelite surfaces follows the order(101)>(112)>(001).So,(112)and(001)surfaces are the main cleavage and exposure surfaces in nature.(112)surfaces have higher hydrophilcity than(001)because of the higher D_(b).The anisotropy of surface electrical properties and adsorption could be explained by the differences in the active oxygen,calcium sites and their broken bonds.(112)and(101)surfaces have better reactivity with reagents due to more broken bonds of active Ca.(001)surfaces have higher active oxygen atom density,which promoted the better combinations of OH^(-)by the hydrogen-bond interaction and higher negative surface potential.The exposure of highly active crystal surfaces and shape parameters of scheelite particles can be tuned by optimizing the grinding process,and hence enhancing its flotation.Overall,the research results is of great value for the efficient flotation separation of scheelite.
作者
汪聪
邓建
王建军
孙磊
孙伟
肖庆飞
曹亦俊
高志勇
WANG Cong;DENG Jian;WANG Jianjun;SUN Lei;SUN Wei;XIAO Qingfei;CAO Yijun;GAO Zhiyong(School of Minerals Processing and Bioengineering,Central South University,Changsha 410083,China;Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources,Central South University,Changsha 410083,China;Institute of Multipurpose Utilization of Mineral Resource,Chinese Geological Survey,Chengdu 610041,China;Faculty of Land Resource Engineering,Kunming University of Science of Technology,Kunming 650093,China;Chemical Engineering College,Zhengzhou University,Zhengzhou 450001,China)
出处
《金属矿山》
CAS
北大核心
2021年第6期15-25,共11页
Metal Mine
基金
国家自然科学基金项目(编号:U2067201,51774328)
国家重点研发计划项目(编号:2021YFE0106800,2020YFC1909202)
湖南省杰出青年科学基金项目(编号:2020JJ2044)
湖南省“湖湘青年英才”支持计划(编号:2018RS3011)
国家111创新引智基地项目(编号:B14034)。
关键词
白钨矿
表面断裂键
解理面
表面能
润湿性
表面电性
浮选
磨矿
scheelite
surface broken bond
cleavage surface
surface energy
wettability
surface electrokinetic
flotation
grinding
作者简介
汪聪(1997-),男,硕士研究生;通信作者:高志勇(1985-),男,教授,博士研究生导师。
