以钢渣为原料合成层状双氢氧化物及其结构表征  

Synthesis and structural characterization of layered double hydroxide using steel slag as raw material

作　　者：陈艳[1,2] 王丽秋[1] 王晨晔[2] 李会泉[2] 

机构地区：[1]燕山大学环境与化学工程学院,河北秦皇岛066004 [2]中国科学院过程工程研究所绿色过程与工程重点实验室,湿法冶金清洁生产技术国家工程实验室,北京100190

出　　处：《化工学报》2015年第12期5149-5156,共8页CIESC Journal

基　　金：国家科技支撑计划(2013BAC12B04)~~

摘　　要：以钢渣为原料,醋酸为浸出介质,在一定条件下得到浸出液,利用共沉淀法合成了Ca-Mg-Al-Fe四元层状双金属氢氧化物（LDHs）,探讨了pH、晶化温度和晶化时间对Ca-Mg-Al-Fe四元LDHs层状材料合成的影响,采用XRD、XRF、SEM、FT-IR、TEM、DTA/TG和BET对样品进行了表征。研究表明,pH对层状材料合成的影响最大,pH在10.5~11.8可形成纯相水滑石;晶化温度和晶化时间是影响晶格参数和层间距的重要因素,随温度及时间的增加,其晶格参数a、c及层间距均先减小后增大;LDHs的晶粒尺寸沿a轴方向比沿c轴方向大。当pH=11.8,晶化温度150℃,晶化时间16 h时,合成的LDHs层状材料结构规整、晶型良好、层状结构明显、孔径较大且热稳定性良好。Ca-Mg-Al-Fe quaternary layered double hydroxide（LDHs） was successfully synthesized using the abundant and cheap steel slag as raw material via a convenient chemical process： acetic acid-leaching and coprecipitation. The influences of pH value, crystallization temperature and time on the synthesis of Ca-Mg-Al-Fe quaternary LDHs were investigated. The samples were characterized by XRD, XRF, SEM, FT-IR, TEM, DTA/TG and BET. The results showed that pH was the dominant factor for the synthesis of LDHs, and pure LDHs could be synthesized when pH value was controlled in the range of 10.5 — 11.8 during coprecipitation process. Crystallization temperature and time were important factors influencing the crystal cell parameters and layer spacing. As the crystallization temperature and time increased, lattice parameters a, c and the spacing of layer first reduced and then increased. Crystal grain size of LDHs along the axis of a was larger than that along the axis of c. When LDHs was synthesized at the conditions of pH of 11.8, crystallization temperature of 150 ℃ and crystallization time of 16 h, it presented well-defined structure and crystal shape, clear layered structure, large aperture and well thermal stability.

关 键 词：钢渣 LDHS 合成 结晶 纯化 

分 类 号：X705[环境科学与工程—环境工程]