摘要
将农业废弃物资源化利用与废水处理相结合,研制对水中重金属具有优异选择性吸附和深度去除能力的生物质功能材料。采用简单、绿色的浸渍-原位沉淀法将水合氧化铁(HFO)以纳米颗粒的形式稳定负载在向日葵茎髓表面,制得纳米复合材料SSP-HFO。比表面积分析(BET)和带能谱的扫描电镜(SEM-EDS)测定结果表明,SSP-HFO比表面积为110m^(2)/g,是原材料的50倍,分布在葵杆茎髓表面的HFO纳米颗粒纳直径为50~100nm。在50mL 10mg/L铜溶液中,0.03g SSP-HFO复合材料对Cu^(2+)的去除率达到100%。pH偏酸性时吸附能力下降,pH接近中性时吸附效果最佳。溶液中共存的Na^(+)、Mg^(2+)和Ca^(2+)等竞争离子对Cu^(2+)的吸附去除影响不大,表明SSP-HFO对重金属具有良好的吸附选择性。吸附等温线符合Langmuir方程,吸附动力学遵循准一级和二级动力学模型描述。SSP-HFO固定床柱吸附在竞争离子共存时能够将5mg/L Cu^(2+)降低至0.1mg/L以下,处理水体积约为4250mL,吸附饱和后用NaCl和NH_(3)·H_(2)O混合溶液脱附再生,脱附率接近100%。SSP-HFO纳米复合材料在pH>2的酸、碱、盐溶液中未见Fe的流失,具备优异的稳定性,且重复利用性能好,6次吸附脱附循环后对Cu(Ⅱ)的去除率保持在90%以上。
This paper combined the resource utilization of agricultural waste with wastewater treatment to develop biomass functional materials with excellent selective adsorption and deep removal capabilities for heavy metals in water.A simple and green impregnation in-situ precipitation method was used to stably load hydrated iron oxide(HFO)in the form of nanoparticles on the surface of sunflower stem pith,and a nanocomposite material SSP-HFO was prepared.The BET and SEM-EDS results showed that the specific surface area of SSP-HFO was 110m^(2)/g,which was 50 times higher than that of the raw material.The HFO nanoparticles distributed on the surface of sunflower stem pith had a diameter of 50~100nm.In 50mL of copper solution at a concentration of 10mg/L,the removal rate of Cu^(2+)by 0.03g SSP-HFO composite material reached 100%.When the pH was slightly acidic,the adsorption capacity decreased,and when the pH was close to neutral,the adsorption effect was best.The coexisting competitive ions such as Na^(+)Mg^(2+)and Ca^(2+)in the solution had little effect on the adsorption and removal of Cu^(2+),indicating that SSP-HFO had good adsorption selectivity for heavy metals.The adsorption isotherm was in accordance with the Langmuir equation,and the adsorption kinetics followed the description of quasi first and second order kinetic models.SSP-HFO fixed bed column adsorption could reduce the Cu^(2+)content from 5mg/L to below 0.1mg/L when competing ions coexisted.The treated water volume was about 4250mL,and after adsorption saturation,it was desorbed and regenerated using a mixed solution of NaCl and NH_(3)·H_(2)O,with a desorption rate of close to 100%.The SSP-HFO nanocomposite material showed no loss of Fe in acid,alkali,or salt solutions with pH>2,exhibiting excellent stability and good reusability.After six adsorption and desorption cycles,the removal rate of Cu(Ⅱ)remained above 90%.
作者
陈权
陈一良
宋文旭
张磊
丁大虎
阮宏华
Chen Quan;Chen Yiliang;Song Wenxu;Zhang Lei;Ding Dahu;Ruan Honghua(College of Ecology and Environment,Nanjing Forestry University,Nanjing 210037;College of Resources and Environmental Sciences,Nanjing Agricultural University,Nanjing 210095)
出处
《化工新型材料》
CAS
CSCD
北大核心
2024年第12期220-227,共8页
New Chemical Materials
基金
国家重点研发计划(2021YFD2200403)
中国博士后科学基金项目(2017M621755)。
关键词
向日葵茎髓
水合氧化铁
纳米复合材料
吸附
重金属
sunflower stem pith
hydrated iron oxides
nanocomposites
adsorption
heavy metal
