表面纳米修饰白云石的反应动力学及其性能表征  

Reaction kinetics and characterization of surface nanometer modified dolomite

作　　者：吴成宝[1,2] 杨玉芬[2] 盖国胜[2] 林列书[1] WU Chengbao;YANG Yufen;GAI Guosheng;LIN Lie(School of Aircraft Maintenance Engineering,Guangzhou Civil Aviation Vocational and Technical College,Guangzhou Guangdong 510470,China;School of Materials Science and Engineering,Tsinghua University,Beijing 100084,China)

机构地区：[1]广州民航职业技术学院飞机维修工程学院,广东广州510470 [2]清华大学材料科学与工程学院,北京100084

出　　处：《化工矿物与加工》2019年第6期43-47,共5页Industrial Minerals & Processing

基　　金：国家自然科学基金项目(50974079)

摘　　要：为减少白云石表面的锐利棱角和在粉碎过程中形成的晶体解理面,采用化学沉积法在Ca(OH)2-CO2-H2O体系中制备了表面纳米修饰白云石粉体,探索了其反应机理,表征了表面修饰前后的白云石的物理性能。研究表明:随着反应的进行,反应体系的pH值在相对较长的时间内保持不变,然后急剧降低,下降到最小值后保持不变;电导率先保持不变,然后急剧降低到一定值,接着有所上升,最后保持在一定值;体系温度先上升,达到一定值后下降。经表面纳米修饰后,白云石颗粒的表面棱角被钝化,晶体解理面减少,形貌得到改善,粉体的平均粒径减小,白度降低,松装密度和振实密度增加,流动性增强,飞扬性上升,比表面积增大。In order to reduce the sharp edges on the surface of dolomite and the crystal cleavage surface formed in the crushing process,the nano-modified dolomite powders were prepared by chemical deposition method in the Ca(OH)2-CO_2-H2 O system,and the reaction mechanism was explored to characterize the physical properties of dolomite before and after surface modification.The study show that as the reaction progresses,the pH value of the reaction system remains unchanged for a relatively long time,and then decreases sharply,remaining unchanged after dropping to the minimum value.Conductance first stays the same,then drops sharply to a certain value,then rises,and finally stays at a certain value.The temperature of the system rises first and then decreases after reaching a certain value.After nanometer surface is modified,the surface edges and corners of dolomite particles were passivated,the cleavage surface is reduced,and the morphology is improved.The average particle size of powder decreases,whiteness decreases,loose packing density and vibration density increase,the fluidity is improved,the flying ability is enhanced,and the specific surface area is increased.

关 键 词：反应机理 纳米表面修饰 白云石 制备 

分 类 号：TB332[一般工业技术—材料科学与工程]