酸处理对蒙脱石结构及理化性能的影响  

The effect of sulfuric acid treatment on the structure and physical&chemical properties of montmorillonite

作　　者：田景斐 孙红娟[1,2,3] 彭同江 Tian Jingfei;Sun Hongjuan;Peng Tongjiang(Key Laboratory of Solid Waste Treatment and Recycling of Ministry of Education,Southwest University of Science and Technology,Mianyang Sichuan 621010,China;Institute of Mineral Materials and Applications,Southwest University of Science and Technology,Mianyang Sichuan 621010,China;Sichuan Nonmetallic Mineral Powder Modification and High Qualitative Utilization Technology Engineering Laboratory,Mianyang Sichuan 621010,China)

机构地区：[1]西南科技大学固体废物处理与资源化教育部重点实验室,四川绵阳621010 [2]西南科技大学矿物材料及应用研究所,四川绵阳621010 [3]四川省非金属矿粉体改性与高质化利用技术工程实验室,四川绵阳621010

出　　处：《化工矿物与加工》2022年第1期12-17,共6页Industrial Minerals & Processing

基　　金：国家自然科学基金(41972042)。

摘　　要：膨润土原矿经不同浓度的硫酸处理后得到一系列成分、结构及物化性能有差异的样品,通过对各阶段反应产物的物相结构、化学成分、显微形貌等的分析研究,以及对硫酸处理前后样品的阳离子交换容量、吸蓝量、膨胀容等性能的测定发现:硫酸用量少时,不会破坏蒙脱石的铝氧八面体结构;但随着硫酸用量的增加,溶液中的H^(+)会不断侵蚀并破坏蒙脱石的双八面体结构,使其中的铝、镁、铁的金属氧化物不同程度地溶出;阳离子交换容量、吸蓝量、膨胀容等均随着硫酸用量的增加出现不同程度的下降,其下降程度与对应酸化产物的d_(001)特征峰的半高宽的增加成负相关,与相对结晶度成正相关。酸活化后的蒙脱石成分、结构以及理化性能发生变化的主要原因是酸化过程中溶液体系中的氢离子与蒙脱石层间阳离子发生了置换,且破坏了蒙脱石的层状结构。Bentonite ore was treated with different concentrations of sulfuric acid to obtain a series of samples with different composition,structure and physical&chemical properties.Upon the analysis and study on the phase structure,chemical composition and microscopic morphology of the reaction products at each stage,and determination of the cation exchange capacity(CEC),blue absorption volume and swelling capacity of the samples before and after the acid treatment,it was found that:little sulfuric acid consumption will not lead to damage of the alumino octahedron structure of montmorillonite.With the increased addition of sulfuric acid,the dioctahedron structure of montmorillo-nite was rapidly destroyed with the constant corrosion due to the presence of H^(+) ion in the solution,which facilitated the oxides of aluminum,magnesium and iron to dissolve out of the structure at different rates.CEC,blue absorption volume,and swelling properties will drop at different rates that was negatively correlated with the increased FWHM of the characteristic peak of the acidification product d_(001),and positively correlated with the relative crystallinity.Any changes of the composition,structure and physical&chemical properties of the montmorillonite after acid activation were mainly owing to the replacement of the cations between the montmorillonite layers by the hydrogen ions in the solution during the acidification process and due to the destruction of the layered structure of montmorillonite.

关 键 词：膨润土 蒙脱石 酸活化 晶体结构 阳离子交换容量 吸蓝量 膨胀容 

分 类 号：TQ926.1[轻工技术与工程—发酵工程]