碳酸钠改性水葫芦生物炭及其对离子型稀土矿地表水中Pb^(2+)和Ni^(2+)的吸附  

Modification of water hyacinth biochar with sodium carbonate and removal of Pb^(2+)and Ni^(2+)from surface water of ionic rare earth mines

作　　者：叶成宇 马星宇 束鑫 张华林[2] 彭正壮 李庭刚 袁文静 YE Chengyu;MA Xingyu;SHU Xin;ZHANG Hualin;PENG Zhengzhuang;LI Tinggang;YUAN Wenjing(School of Rare Earths,University of Science and Technology of China,Hefei,230026,China;Key Laboratory of Rare Earths,Jiangxi Institute of Rare Earths,Ganjiang Innovation Academy,Chinese Academy of Sciences,Ganzhou,341119,China;CAS Key Laboratory of Green Process and Engineering,Innovation Academy for Green Manufacture,National Engineering Research Center of Green Recycling for Strategic Metal Resources,Beijing Engineering Research Centre of Process Pollution Control,Institute of Process Engineering,Chinese Academy of Sciences,Beijing,100190,China;Key Laboratory of Biopharmaceutical Preparation and Delivery,State Key Laboratory of Biochemical Engineering,Institute of Process Engineering,Chinese Academy of Sciences,Beijing,100190,China;University of Chinese Academy of Sciences,Beijing,100049,China)

机构地区：[1]中国科学技术大学稀土学院,合肥230026 [2]中国科学院稀土重点实验室,江西省稀土清洁生产重点实验室,中国科学院赣江创新研究院,赣州341119 [3]中国科学院绿色过程与工程重点实验室,中国科学院绿色过程制造创新研究院,战略金属资源绿色循环利用国家工程研究中心,北京市过程污染控制工程技术研究中心,中国科学院过程工程研究所,北京100190 [4]生物药制备与递送重点实验室(中国科学院),生化工程国家重点实验室,中国科学院过程工程研究所,北京100190 [5]中国科学院大学,北京100049

出　　处：《环境化学》2025年第3期991-1005,共15页Environmental Chemistry

基　　金：江西省技术创新引导类计划项目(20212BDH81029);鄂尔多斯市科技重大专项(2022EEDSKJZDZX014-1);稀土产业基金(IAGM2020DB06);中国科学院重点部署项目(ZDRW-CN-2021-3-3);中国科学院赣江创新研究院自主部署项目(E055A001)资助.

摘　　要：水葫芦制备的生物炭(WHBC)因其多孔结构、丰富的化学表面基团和矿物组成而被认为具有较大的环境修复潜力.为更大程度提升WHBC对重金属离子的吸附能力,本研究以水葫芦为原料,碳酸钠为化学活化剂,采用浸渍法并在高温下热解得到碳酸钠改性水葫芦生物炭(SWHBC),并以Pb^(2+)和Ni^(2+)的吸附性能为考察对象,在单因素实验的基础上,采用响应曲面法-Box-Behnken Design(BBD)设计对改性生物炭材料的加热时间、加热温度和浸渍质量比(Na2CO_(3)/WH,g·g^(−1))等3种基本制备条件进行优化.结果表明,最佳制备条件是浸渍质量比为1.41、温度为421.79℃和加热时间为2.90 h.最优条件下所制备的SWHBC对Pb^(2+)和Ni^(2+)的实际吸附量分别为758.42 mg·g^(−1)和118.19 mg·g^(−1).用拟二级动力学模型和Langmuir模型能更好地拟合吸附过程,获得的SWHBC对Pb^(2+)和Ni^(2+)最大理论吸附能力分别为1247.085 mg·g^(−1)和147.091 mg·g^(−1).采用SEM、BET、EA、XRD以及FTIR对WHBC和SWHBC的形貌、比表面积、元素组成、矿物类型和官能团进行表征.结果表明,碳酸钠在热解过程中产生化学活化促进生物炭比表面积、极性和含氧官能团的增加,通过极性官能团和含氧官能团与重金属的络合作用以及孔隙扩散吸附重金属.并且碳酸钠和水葫芦中的KCl和CaCO_(3)反应生成的Nyerereite矿物在吸附过程中参与了离子交换和共沉淀作用.因此SWHBC吸附重金属离子的主要机理包括离子交换、共沉淀、表面络合作用和孔隙扩散.SWHBC对离子型稀土矿山受污染地表水中多种金属离子具有显著去除效果,其中对Pb^(2+)和Ni^(2+)的去除率达到了99.98%和88.77%,处理后Pb^(2+)的浓度达到了《地表水环境质量标准》(GB3838—2002)Ⅰ类水标准,表明本研究所制备材料是一种去除受污染水体中Pb^(2+)和Ni^(2+)的有效吸附剂.Biochar prepared from water hyacinth(WHBC)is considered to have significant environmental remediation potential due to its porous structure,abundant chemical surface groups and mineral composition.In order to further enhance the adsorption capacity of WHBC on heavy metal ions,water hyacinth was used as the raw material and sodium carbonate as a chemical activator in this study.The sodium carbonate-modified water hyacinth biochar(SWHBC)was obtained through impregnation and pyrolysis under high temperatures.The adsorption performance of SWHBC on Pb^(2+)and Ni^(2+)were further investigated and optimized by response surface methodology-Box-Behnken Design(BBD),based on one-way experiment under three basic preparation conditions including heating time,heating temperature and impregnation mass ratio(Na2CO_(3)/WH,g·g^(−1)).The results showed that the optimal preparation conditions were an impregnation mass ratio of 1.41 and heating at 421.79℃for 2.90 hours.The actual adsorption capacities of Pb^(2+)and Ni^(2+)by SWHBC prepared under the optimal conditions were 758.42 mg·g^(−1)and 118.19 mg·g^(−1),respectively.The adsorption process was better fitted by pseudo-second-order kinetic and Langmuir models,and the maximum theoretical adsorption capacities of SWHBC for Pb^(2+)and Ni^(2+)were 1247.085 mg·g^(−1)and 147.091 mg·g^(−1),respectively.In addition,the morphology,specific surface area,elemental composition,mineral type and functional groups of WHBC and SWHBC were characterized by SEM,BET,EA,XRD and FTIR.The results showed that the chemical activation of sodium carbonate during the pyrolysis process promoted the increase of specific surface area,polarity and oxygenated functional groups of the biochar,which led to the adsorption of heavy metals through complexation with heavy metals and pore diffusion of the polar and oxygenated functional groups.In addition,Nyerereite minerals generated by the reaction between sodium carbonate and KCl and CaCO_(3)in the water hyacinth were involved in ion exchange and co-

关 键 词：水葫芦 碳酸钠 生物炭 重金属 吸附机理 响应面法 

分 类 号：X-1[环境科学与工程] O6[理学—化学]