蛇纹石表面特性研究

Surface Property of Serpentine

通过溶解试验、扫描电镜、Zeta电位测试及XPS多种手段,对蛇纹石表面特性进行了分析.试验结果表明,在水溶液中,蛇纹石表面易发生溶解,使矿浆p H值呈碱性,并表现出较强的缓冲能力.溶解后蛇纹石的表面形貌发生很大变化,出现较多凸起状、絮状结构,并且其表面元素含量也较溶解前有较大差异.此外,从蛇纹石晶体结构上对其机理进行了讨论.结果表明,经磨碎后蛇纹石表面易暴露出大量Mg2+,—OH,并进入溶液中使得溶液中Mg含量及p H值显著升高.同时,细粒级蛇纹石表面暴露的—OH越多,使得矿浆p H值变化越快,p H值也越高.

Dissolution experiments,SEM,Zeta potential tests and XPS are used to analyse the surface property of serpentine.The results showed that the surface of serpentine is prone to dissolve in aqueous solution and make pulp pH alkaline,which reveals strong buffer ability.Compared with undissolved serpentine,embossment and flocculent structure are observed on the surface topography of dissolved serpentine.Besides,the surface elements content also has a big diffrence.The crystal structure of serpentine was discussed to understand the dissolution mechanism.The result indicated that large amounts of Mg 2+and-OH expose on serpentine surface after grinding and transfer to aqueous solution which leading to a high pH value and high content of Mg 2+of pulp.Furthermore,because of more-OH exposed on fine-grained serpentine surface,the rise of pH value is more remarkable and higher pH value is obtained.