HBP-NH_(2)的制备及其对尾矿中重金属的淋洗效果  

Preparation of Amino-terminal Hyperbranched Polymer and Its Effectiveness of Leaching Heavy Metal in Tailings

作　　者：李美兰 张富莹[1] 王丽文 张兴隆 罗娜 龚伟 刘白玲 LI Meilan;ZHANG Fuying;WANG Liwen;ZHANG Xinglong;LUO Na;GONG Wei;LIU Bailing(Key Lab of Comprehensive Utilization of Tailings Resources in Shaanxi Province,Shangluo University,Shangluo 726000,China;Chengdu Institute of Organic Chemistry,CAS,Chengdu 610041,China)

机构地区：[1]商洛学院,陕西省尾矿资源综合利用重点实验室,陕西商洛726000 [2]中国科学院成都有机化学研究所,四川成都610041

出　　处：《环境科学与技术》2021年第8期30-38,共9页Environmental Science & Technology

基　　金：陕西省科技厅项目(2019JQ-908);陕西省大学生创新创业训练计划项目(S202011396027);商洛市科技局重点项目(2020-Z-0032);商洛学院人才引进计划项目(16SKY026)。

摘　　要：文章将丙烯酸甲酯与二乙烯三胺进行迈克尔加成及酰胺化反应,制备出了端氨基超支化聚酰胺(HBP-NH_(2)),采用FTIR表征了其化学结构,并研究了所制备的HBP-NH_(2)在不同因素影响下对尾矿中重金属Cd、Pb和Zn的淋洗修复效果。实验结果表明,相较于柠檬酸(CA),HBP-NH_(2)对尾矿中Cd、Pb和Zn具有更好的淋洗效果,当淋洗时间t=120 min,pH=6.5,CHBP-NH_(2)=2.0%及液固比为20∶1时,HBP-NH_(2)对尾矿中Cd、Pb和Zn的去除率分别为79.3%、75.2%和57.9%。另外,HBP-NH_(2)对尾矿中不同重金属的淋洗顺序为Cd>Pb>Zn。使用HBP-NH_(2)淋洗后,有利于尾矿表层颗粒在风蚀作用下更加稳定,促进矿区生态修复。在淋洗废液中添加Ca(OH)_(2)可实现Cd的沉淀而达到有效去除,且Ca(OH)_(2)添加浓度为25 g/L时,淋洗废液中Cd的去除效果最佳,可达96.3%,此时基本满足《污水综合排放标准》(GB 8978-1996)的排放要求。因此,HBP-NH_(2)可以作为环境友好型化学淋洗剂用于矿区污染控制与生态修复。This paper reported on preparation of amino-terminated hyperbranched polyamide(HBP-NH_(2))in the laboratory by means of Michael addition and amidation with diethylenetriamine and methyl acrylate as reaction monomers,and the structure of HBP-NH_(2) was characterized by FTIR.Thereafter,the remediation effects of HBP-NH_(2) to leach out heavy metals including Cd,Pb and Zn in tailings under different conditions were investigated.The experimental results showed that compared with citric acid(CA),HBP-NH_(2) has better leaching effects in terms of Cd,Pb and Zn in tailing.When t=120 min,pH=6.5,CHBP-NH_(2)=2.0%and liquid-solid ratio was 20∶1,the removal rates of Cd,Pb and Zn in tailing by HBP-NH_(2) were79.3%,75.2%and 57.9%,respectively.Moreover,the leaching effectiveness by HBP-NH_(2) with respect of the three kinds of heavy metal was Cd>Pb>Zn;and application of HBP-NH_(2) leaching could improve stability strength against wind erosion of the tailing particles of surface layer in the tailing pond,conducive to ecological restoration of mining area.Besides,Cd could be effectively removed of the leaching wastewater by addition of Ca(OH)_(2),and Ca(OH)_(2) concentration of 25 g/L was proved the best for Cd removal from leaching wastewater,with the effectiveness up to 96.3%,which basically could meet the discharge requirements of the related national standard,i.e.,Comprehensive Sewage Discharge Standard(GB 8978-1996).Therefore,this study suggested that HBP-NH_(2) as an environmental friendly chemical leaching agent could be used for pollution control and ecological restoration in mining area.

关 键 词：端氨基超支化聚酰胺 生态修复 淋洗 重金属 绿色淋洗剂 

分 类 号：X75[环境科学与工程—环境工程]