氢氧化钠对地质聚合物制备及高温力学性能影响  

Effect of Sodium Hydroxide on Preparation and High Temperature Mechanical Properties of Geopolymers

作　　者：李洁[1] 伊元荣[1,2,3] 刘伟[1] 李春辉 迪娜·加阿拜 佳素然·阿比利米提亚夏尔 LI Jie;YI Yuanrong;LIU Wei;LI Chunhui;DINA Jaabay;JASURA Ablimityaxar(School of Ecology and Environment,Xinjiang University,Urumqi 830046,China;Key Laboratory of Xinjiang Oasis Ecology,Ministry of Education,Urumqi 830046,China;Field Scientific Observatory of the Ministry of Education for Temperate Desert Ecosystems,Urumqi 830046,China)

机构地区：[1]新疆大学生态与环境学院,新疆乌鲁木齐830046 [2]新疆绿洲生态教育部重点实验室,新疆乌鲁木齐830046 [3]新疆精河温带荒漠生态系统教育部野外科学观测研究站,新疆乌鲁木齐830046

出　　处：《环境科学与技术》2024年第5期46-54,共9页Environmental Science & Technology

基　　金：新疆自然科学基金资助项目(2022D01C388)。

摘　　要：该研究旨在探索锂辉石尾矿与精炼渣的资源化利用新途径。通过单因素实验和正交实验,分析了氢氧化钠添加量、水玻璃添加量和锂辉石尾矿与精炼渣掺量比对地质聚合物力学性能的影响。在此基础上,重点分析了氢氧化钠添加量对锂辉石尾矿-精炼渣基地质聚合物制备力学性能的影响,采用XRD、SEM、FT-IR等表征手段分析了氢氧化钠对地质聚合物微观结构的影响。研究结果表明,锂辉石尾矿与精炼渣掺比量为7∶3、水玻璃添加量为15 mL、氢氧化钠添加量为2 g的条件下,制备地质聚合物28 d抗压强度可达26.78 MPa。氢氧化钠添加量对地质聚合物制备的影响最为显著,当锂辉石尾矿的碱度过高时,会减缓或抑制硅氧四面体和铝氧四面体的溶出,从而影响了C-S-H凝胶和N-A-S-H凝胶的合成。XRD和SEM分析显示,随着氢氧化钠含量的增加,生成的凝胶先增多后减少,同时与蓝晶石等物质结合,提高了地质聚合物的致密程度。此外,在800℃下,锂辉石尾矿-精炼渣基地质聚合物的抗压强度损失较小,表明其具有良好的耐高温性能。The aim of this study is to explore new ways of resource utilization of lithium pyroxene tailings and refining slag.The effects of sodium hydroxide addition,water glass addition and the doping ratio of lithium pyroxene tailings and refining slag on the mechanical properties of geopolymers were analyzed through one-way and orthogonal experiments.On this basis,we focused on the influence of the change of sodium hydroxide addition on the preparation of lithium pyroxene tailings-refin-ing slag based geopolymer and its mechanical properties,and analyzed the influence of sodium hydroxide on the microstruc-ture of geopolymer by using the characterization means such as XRD,SEM,FT-IR and so on.The results showed that the 28 d compressive strength of the geopolymer was up to 26.78 MPa when the ratio of lithium pyroxene tailings to refinery slag was 7∶3,the addition of water glass was 15 mL,and the addition of sodium hydroxide was 2 g.The addition of sodium hydroxide had the most significant effect on the preparation of geopolymer among the three influencing factors.When the alkalinity of lithium pyroxene tailings was too high,the dissolution of silica-oxygen tetrahedra and aluminium-oxygen tetra-hedra was slowed down or inhibited,thus affecting the synthesis of C-S-H gels and N-A-S-H gels.XRD and SEM anal-yses showed that,with the increase of the content of sodium hydroxide,the generated gels firstly increased and then decreased,and at the same time,they combined with the substances such as bluestone,which increased the degree of densification of the geopolymer.In addition,the loss of compressive strength of the lithium pyroxene tailings-refinery slag-based geopolymer was small at 800℃,indicating its good high temperature resistance.

关 键 词：锂辉石尾矿 精炼渣 氢氧化钠添加量 凝胶物质 地质聚合物 

分 类 号：X753[环境科学与工程—环境工程]