摘要
以含钙聚合铝(PACCa)作为导向剂与铝源,在常温常压下合成了微/纳结构(微米/纳米尺度)的弗雷德盐。当水溶液中的ρ(Cu2+)为4.406 mg/L时,每升含铜溶液投入0.45 g弗雷德盐对Cu2+的去除率为99.02%。背散射(BEI)与二次电子(SEI)的SEM研究表明:微/纳结构的弗雷德盐在水处理中经历了溶解-结晶过程,XRD鉴定证实弗雷德盐分解后形成方解石晶体与无定形氧化铝。微/纳结构的弗雷德盐去除Cu2+的絮凝沉淀机理与吸附反应模式有所不同,弗雷德盐在絮凝过程中与水中CO2作用转变成方解石与无定形氧化铝,同时Cu2+在碱性环境下生成氢氧化物,新生成的无定型氢氧化铝迅速吸附铜的氢氧化物并裹挟方解石沉淀。
Micro/nano structural Friedel＇s salts was synthesized by using calcium-containing polyaluminum chloride （PACCa） as nucleation gel and row material of aluminum source, at room temperature and under atmospheric pressure. Friedel＇s salts also named chlorinated lamellar double hydroxide （LDHs） of composition 3CaO.Al2O3·CaC12-10H20. It was firstly used as flocculant-adsorbent for removing copper from waste water. 0.45 g/L of Friedel＇s salts could remove 99.02% of copper from aqueous solution of p（Cu2＋）=4.406 mg/L. Backscattered （BEI） and secondary electron （SEI） SEM study show dissolving-recrystallization process in water treatment by using micro/nano structural Friedel＇s salts. XRD identification Confirms entire decomposition of Friedel＇s salts and crystallization of rhombohedron calcite and amorphous alumina. This study indicates that the machanism of removing Cu2＋ by micro/nano structural Friedel＇s salts with flocculation is different from that of adsorption. In flocculating progress, micro/nano structural Friedel＇s salts react with CO2 and reform rhombohedron calcite and amorphous alumina. At the same time, Cu2＋ is oxidized in alkaline environment and forms metal hydroxides, and is rapidly adsorbed by amorphous aluminum hydroxide, and involves crystal of rhombohedron calcite to be co-precipitation.
出处
《矿物学报》
CAS
CSCD
北大核心
2012年第4期548-554,共7页
Acta Mineralogica Sinica
基金
贵州省省长专项资金项目(编号:[2009]04)
贵州省高层次人才特助经费资助(TZJF[2009]18号)
关键词
弗雷德盐
除铜
BEI-SEI
溶解-结晶
絮凝-吸附
Friedel＇s salts
2＋ Cu , removal
BEI-SEI
dissolve-crystallization
flocculation-adsorption
