ZVI/nZVI凭借其优异的污染物去除性能以及在环境修复中的其他优点,引起了国内外研究人员的极大关注。基于中国知网和Web of Science核心合集数据库中英文文献数据,对国内外微生物协同零价铁(ZVI)/纳米零价铁(nZVI)的相关文献进行年代分...ZVI/nZVI凭借其优异的污染物去除性能以及在环境修复中的其他优点,引起了国内外研究人员的极大关注。基于中国知网和Web of Science核心合集数据库中英文文献数据,对国内外微生物协同零价铁(ZVI)/纳米零价铁(nZVI)的相关文献进行年代分布、期刊分布、关键词共现、时间演进及突现等方面的文献计量分析。结果显示,年度论文总数的增长趋势可分为3个阶段。中国是这一领域最活跃的国家,Journal of Hazardous Materials是出版物数量最多的期刊。有关ZVI与微生物的研究重点是甲烷生产、厌氧消化、脱氯作用;微生物协同nZVI的研究集中于微生物群落、修复、生物毒性、生物炭。关键词的时间演进图谱将其分为9种聚类,关键词的突现分析表明细胞分子水平的机理研究和零价铁生物毒性的创新可能是未来的研究方向。展开更多
以辉钼矿(MoS_(2))、褐铁矿和无烟煤为原料,通过碳热还原法制备了MoS_(x)@ZVI复合材料。研究了MoS_(2)用量、焙烧温度、无烟煤用量和焙烧时间对MoS_(x)@ZVI去除酸性橙G(OG)的影响,并确定了制备MoS_(x)@ZVI的较优制备条件为焙烧温度1000...以辉钼矿(MoS_(2))、褐铁矿和无烟煤为原料,通过碳热还原法制备了MoS_(x)@ZVI复合材料。研究了MoS_(2)用量、焙烧温度、无烟煤用量和焙烧时间对MoS_(x)@ZVI去除酸性橙G(OG)的影响,并确定了制备MoS_(x)@ZVI的较优制备条件为焙烧温度1000℃、MoS_(2)用量6%、焙烧时间60 min和无烟煤用量25%。通过X射线衍射、扫描电子显微镜和能谱仪对较优条件制备的MoS_(x)@ZVI进行表征,结果表明,材料中生成了大量核壳结构的硫化零价铁,内核为Fe-Mo-C合金,外壳可能由硫化钼、FeS、C、钼氧化物和铁氧化物组成。降解实验结果表明,将较优条件制备的MoS_(x)@ZVI碎磨至粒径<0.1 mm,用0.6 g MoS_(x)@ZVI处理400 mL 200 mg/L OG模拟废水,在初始pH=3.0~10.0范围处理150 min,OG的去除率均在90%以上。展开更多
为研究ZVI/Cu(铁/铜)双金属体系的降解能力,制备了不同理论Cu质量载荷(0.05、0.11、0.24、0.41和1.26 g Cu/g ZVI)的ZVI/Cu双金属颗粒。利用制备所得的ZVI/Cu双金属颗粒活化过硫酸钠(PDS)产生的硫酸根自由基(SO^-4·)作为氧化剂降...为研究ZVI/Cu(铁/铜)双金属体系的降解能力,制备了不同理论Cu质量载荷(0.05、0.11、0.24、0.41和1.26 g Cu/g ZVI)的ZVI/Cu双金属颗粒。利用制备所得的ZVI/Cu双金属颗粒活化过硫酸钠(PDS)产生的硫酸根自由基(SO^-4·)作为氧化剂降解偶氮染料甲基橙(MO)。研究了不同因素对目标产物降解效率的影响,包括有Cu质量载荷、ZVI/Cu双金属颗粒的加入量、过硫酸钠的浓度、pH值、温度。实验结果表明ZVI/Cu双金属相对于单纯的Cu和ZVI具有更加优异的催化降解能力,因此可以得出结论在零价铁上沉积一层过渡金属Cu可以有效提高活化能力,以达到提升降解能力的效果;在MO初始浓度为50 mg/L、PDS加入量为5.0 mmol/L、ZVI/Cu双金属颗粒加入量为0.15 g/L、初始pH值为4.0、温度为30℃的条件下,反应进行60 min MO降解率达到86.4%。展开更多
Although widely used in permeation reaction barrier(PRB)for strengthening the removal of various heavy metals,zero-valent iron(ZVI)is limited by various inherent drawbacks,such as easy passivation and poor electron tr...Although widely used in permeation reaction barrier(PRB)for strengthening the removal of various heavy metals,zero-valent iron(ZVI)is limited by various inherent drawbacks,such as easy passivation and poor electron transfer.As a solution,a synergistic system with PRB and electrokinetics(PRB-EK)was established and applied for the efficient removal of Cr(Ⅵ)-contaminated groundwater.As the filling material of PRB,ZVI/Fe_(3)O_(4)/activated carbon(ZVI/Fe_(3)O_(4)/AC)composites were synthesized by ball milling and thermal treatment.A series of continuous flow column experiments and batch tests was conducted to evaluate the removal efficiency of Cr(Ⅵ).Results showed that the removal efficiency of Cr(Ⅵ)remained above 93%even when the bed volume(BV)reached 2000 under the operational parameters(iron/AC mass ratio,2:1;current,5 m A).The mechanism of Cr(Ⅵ)removal by the PRB-EK system was revealed through field emission scanning electron microscopy images,X-ray diffraction,X-ray photoelectron spectroscopy,Fe^(2+) concentration,and redox potential(E h)values.The key in Cr(Ⅵ)reduction was the Fe^(2+)/Fe^(3+) cycle driven by the surface microelectrolysis of the composites.The application of an externally supplied weak direct current maintained the redox process by enhancing the electron transfer capability of the system,thereby prolonging the column lifetime.Cr(Ⅵ)chemical speciation was determined through sequential extraction,verifying the stability and safety of the system.These findings provide a scientific basis for PRB design and the in-situ remediation of Cr(Ⅵ)-contaminated groundwater.展开更多
文摘ZVI/nZVI凭借其优异的污染物去除性能以及在环境修复中的其他优点,引起了国内外研究人员的极大关注。基于中国知网和Web of Science核心合集数据库中英文文献数据,对国内外微生物协同零价铁(ZVI)/纳米零价铁(nZVI)的相关文献进行年代分布、期刊分布、关键词共现、时间演进及突现等方面的文献计量分析。结果显示,年度论文总数的增长趋势可分为3个阶段。中国是这一领域最活跃的国家,Journal of Hazardous Materials是出版物数量最多的期刊。有关ZVI与微生物的研究重点是甲烷生产、厌氧消化、脱氯作用;微生物协同nZVI的研究集中于微生物群落、修复、生物毒性、生物炭。关键词的时间演进图谱将其分为9种聚类,关键词的突现分析表明细胞分子水平的机理研究和零价铁生物毒性的创新可能是未来的研究方向。
文摘以辉钼矿(MoS_(2))、褐铁矿和无烟煤为原料,通过碳热还原法制备了MoS_(x)@ZVI复合材料。研究了MoS_(2)用量、焙烧温度、无烟煤用量和焙烧时间对MoS_(x)@ZVI去除酸性橙G(OG)的影响,并确定了制备MoS_(x)@ZVI的较优制备条件为焙烧温度1000℃、MoS_(2)用量6%、焙烧时间60 min和无烟煤用量25%。通过X射线衍射、扫描电子显微镜和能谱仪对较优条件制备的MoS_(x)@ZVI进行表征,结果表明,材料中生成了大量核壳结构的硫化零价铁,内核为Fe-Mo-C合金,外壳可能由硫化钼、FeS、C、钼氧化物和铁氧化物组成。降解实验结果表明,将较优条件制备的MoS_(x)@ZVI碎磨至粒径<0.1 mm,用0.6 g MoS_(x)@ZVI处理400 mL 200 mg/L OG模拟废水,在初始pH=3.0~10.0范围处理150 min,OG的去除率均在90%以上。
文摘为研究ZVI/Cu(铁/铜)双金属体系的降解能力,制备了不同理论Cu质量载荷(0.05、0.11、0.24、0.41和1.26 g Cu/g ZVI)的ZVI/Cu双金属颗粒。利用制备所得的ZVI/Cu双金属颗粒活化过硫酸钠(PDS)产生的硫酸根自由基(SO^-4·)作为氧化剂降解偶氮染料甲基橙(MO)。研究了不同因素对目标产物降解效率的影响,包括有Cu质量载荷、ZVI/Cu双金属颗粒的加入量、过硫酸钠的浓度、pH值、温度。实验结果表明ZVI/Cu双金属相对于单纯的Cu和ZVI具有更加优异的催化降解能力,因此可以得出结论在零价铁上沉积一层过渡金属Cu可以有效提高活化能力,以达到提升降解能力的效果;在MO初始浓度为50 mg/L、PDS加入量为5.0 mmol/L、ZVI/Cu双金属颗粒加入量为0.15 g/L、初始pH值为4.0、温度为30℃的条件下,反应进行60 min MO降解率达到86.4%。
基金financial support from the National Natural Science Foundation of China(Nos.21906044 and 21477034)the Key Science and Technology Program of Henan Province,China(No.132102210129)+3 种基金the Basic Scientific and Technological Frontier Project of Henan Province(No.162300410046)the Innovation Scientists and Technicians Troop Construction Projects of Henan Province,the Scientific Research Foundation from Soochow University(No.Q416000117)the Technology Department of the Henan Science and Technology Fund Project(No.202102310603)the Cultivating National Scientific Research Project Funds,Henan Normal University(No.5101219170804)。
文摘Although widely used in permeation reaction barrier(PRB)for strengthening the removal of various heavy metals,zero-valent iron(ZVI)is limited by various inherent drawbacks,such as easy passivation and poor electron transfer.As a solution,a synergistic system with PRB and electrokinetics(PRB-EK)was established and applied for the efficient removal of Cr(Ⅵ)-contaminated groundwater.As the filling material of PRB,ZVI/Fe_(3)O_(4)/activated carbon(ZVI/Fe_(3)O_(4)/AC)composites were synthesized by ball milling and thermal treatment.A series of continuous flow column experiments and batch tests was conducted to evaluate the removal efficiency of Cr(Ⅵ).Results showed that the removal efficiency of Cr(Ⅵ)remained above 93%even when the bed volume(BV)reached 2000 under the operational parameters(iron/AC mass ratio,2:1;current,5 m A).The mechanism of Cr(Ⅵ)removal by the PRB-EK system was revealed through field emission scanning electron microscopy images,X-ray diffraction,X-ray photoelectron spectroscopy,Fe^(2+) concentration,and redox potential(E h)values.The key in Cr(Ⅵ)reduction was the Fe^(2+)/Fe^(3+) cycle driven by the surface microelectrolysis of the composites.The application of an externally supplied weak direct current maintained the redox process by enhancing the electron transfer capability of the system,thereby prolonging the column lifetime.Cr(Ⅵ)chemical speciation was determined through sequential extraction,verifying the stability and safety of the system.These findings provide a scientific basis for PRB design and the in-situ remediation of Cr(Ⅵ)-contaminated groundwater.
