原位合成LDHs@地聚物复合材料的矿物组成及除磷效果  

Mineral Composition and Phosphorus Removal Effect of In-situ SynthesizedLDHs@Geopolymer Composites

作　　者：宋学锋[1] 王楠 SONG Xuefeng;WANG Nan(School of Materials Science and Engineering,Xi’an University of Architecture and Technology,Xi’an 710055,China)

机构地区：[1]西安建筑科技大学材料科学与工程学院,西安710055

出　　处：《材料导报》2024年第8期107-112,共6页Materials Reports

基　　金：陕西省科研攻关项目(2018SF-367)。

摘　　要：以高铝粉煤灰、粒化高炉矿渣为前驱体,以氢氧化钠-碳酸钠、氢氧化钙-二水硫酸钙为混合激发剂,原位合成了两种富含层状双金属氢氧化物(LDHs)的粉煤灰-矿渣地聚物复合材料(LDHs@地聚物)。采用XRD、SEM-EDS微观测试手段,分析了LDHs@地聚物的主要矿物组成;以LDHs@地聚物复合材料为吸附剂,采用静态吸附试验考察了其除磷效果。研究结果表明:以氢氧化钠-碳酸钠为激发剂、活性氧化镁为调节材料,原位合成了CO_(3)^(2-)-LDHs@地聚物复合材料;以氢氧化钙-二水硫酸钙为激发剂,原位合成了SO_(4)^(2-)-LDHs@地聚物复合材料。在H_2PO_4~-初始浓度为100 mg·L^(-1)、固液比为1∶100的吸附条件下,掺8%的活性MgO制备的CO_(3)^(2-)-LDHs@地聚物复合材料经热处理后对H_(2)PO_(4)^(-)的吸附容量、去除率分别为9.51 mg·g^(-1)和95.1%;以质量比1∶1的氢氧化钙-二水硫酸钙为激发剂制备的SO_(4)^(2-)-LDHs@地聚物复合材料对H_2PO_(4)^(-)的吸附容量、去除率分别为9.99 mg·g^(-1)和99.9%;相同条件下,SO_(4)^(2-)-LDHs@地聚物复合材料比CO_(3)^(2-)-LDHs@地聚物复合材料具有更优异的除磷效果。Two kinds of fly ash-slag geopolymer composites(LDHs@geopolymer)rich in layered double hydroxides(LDHs)were synthesized in-situ using high-alumina fly ash and granulated blast furnace slag as precursors,sodium hydroxide-sodium carbonate and calcium hydroxide-cal-cium sulfate dihydrate as mixed activators.The main mineral composition of LDHs@geopolymer was analyzed by XRD and SEM-EDS.The phosphorus removal effect of LDHs@geopolymer composites was investigated by static adsorption test.The results show that CO_(3)^(2-)-LDHs@geopolymer composites are synthesized in-situ with sodium hydroxide-sodium carbonate as activator and active magnesium oxide as regulating material.SO_(4)^(2-)-LDHs@geopolymer composites are synthesized in situ using calcium hydroxide-calcium sulfate dihydrate as activator.Under the adsorption conditions of initial H_(2)PO_(4)-concentration of 100 mg·L^(-1)and solid-liquid ratio of 1∶100,the adsorption capacity and removal rate of H_(2)PO_(4)-of CO_(3)^(2-)-LDHs@geopolymer composites prepared by doping 8wt%active MgO after heat treatment are 9.51 mg·g^(-1)and 95.1%,respectively.The adsorption capacity and removal rate of H 2PO 4-of SO_(4)^(2-)-LDHs@geopolymer composites prepared with mass ratio of 1∶1 calcium hydroxide-calcium sulfate dihydrate as activator are 9.99 mg·g^(-1)and 99.9%,respectively.Under the same conditions,SO_(4)^(2-)-LDHs@geopolymer composites have better phosphorus removal effect than CO_(3)^(2-)-LDHs@geopolymer composites.

关 键 词：地质聚合物 活性氧化镁 层状双金属氢氧化物 水滑石 磷吸附 

分 类 号：TB321[一般工业技术—材料科学与工程]