摘要
为研究地聚物的弱碱性激发技术,以湖北某地的页岩提钒尾渣为原料,进行了地聚物碱激发研究。主要研究了不同偏高岭土掺量、激发剂模数和激发剂用量对地聚物抗压强度的影响。最终确定在m(提钒尾渣)∶m(偏高岭土)=9∶1,弱碱性激发剂Na2SiO3的模数为3. 0,Na2SiO3的掺量为14%的激发制度下,地聚物试样3 d的抗压强度即可达到27. 55 MPa,极大地提高了地聚物的抗压性能。对不同模数的硅酸钠下制备的地聚物进行物相转变、化学键变化和微观形貌分析,发现在液体硅酸钠的作用下,页岩提钒尾渣中的石英被进一步溶解;溶解的无定形硅铝物质与液体硅酸钠中的硅酸根反应逐渐生成硅铝凝胶相;液体硅酸钠中的硅酸根起一个诱导作用,液体硅酸钠的模数越高,其硅酸根含量越高,与页岩提钒尾渣中的无定形硅铝物质反应也越迅速,从而生成更多的硅铝凝胶相,促进了地聚物抗压强度的提高,实现了地聚物的安全制备。
In order to study the weak alkaline activation technology of geopolymer,alkali activation of geopolymer was studied using the shale vanadium tailings in Hubei Province as raw materials.The effects of different addition of metakaolin,modulus of activator and dosage of activator on the compressive strength of geopolymer were studied. Finally,the compressive strength of the geopolymer sample can reach 27. 55 MPa in 3 days under the activation system of m( shale vanadium tailings) ∶m( metakaolin) is 9 ∶1,the modulus of weak alkaline activator Na2SiO3 is 3. 0 and the dosage of activator is 14%,which greatly improves the compressive performance of the geopolymer.The phase transition,chemical bond change and micro-morphology of the geopolymers prepared under different modulus sodium silicate were analyzed. It was found that the quartz in the vanadium tailings is further dissolved under the action of liquid sodium silicate. The dissolved amorphous silicon and aluminum compounds react with silicates in liquid sodium silicate to form silica-alumina gel phases. Silicates in the liquid sodium silicate acts as an inducer,the higher the modulus of the liquid sodium silicate is,the higher the content of silicates is,and the faster the reaction between the liquid sodium silicate and amorphous silicon and aluminum compounds in vanadium tailings is.Thus,more silica-alumina gel phases are formed and the compressive strength of geopolymer is improved,and the safe preparation of geopolymer has been realized.
作者
孟锐
刘涛
张一敏
MENG Rui;LIU Tao;ZHANG Yimin(State Environmental Protection Key Laboratory of Mineral Metallurgical Resources Utilization and Pollution Control,Wuhan University of Science and Technology,Wuhan 430081,Hubei Provience,China;Hubei Collaborative Innovation Center for High Efficient Utilization of Vanadium Resources,Wuhan University of Science and Technology,Wuhan 430081,Hubei Provience,China;Hubei Provincial Engineering Technology Research Center of High efficient Cleaning Utilization for Shale Vanadium Resource,Wuhan University of Science and Technology,Wuhan 430081,Hubei Provience,China)
出处
《矿产保护与利用》
2019年第3期63-68,共6页
Conservation and Utilization of Mineral Resources
基金
国家重点研发计划项目(2018YFC1900602)
关键词
钒尾渣
地聚物
激发剂
胶凝材料
vanadium tailings
geopolymers
activators
cementitious materials
