粉煤灰基多孔材料负载纳米铁的制备及其对龙胆紫的去除效果

为制备新型可再生吸附反应材料,以工业废弃物粉煤灰、棕榈壳等为主要原料,烧结制备FAP（粉煤灰基多孔材料）,并以FAP为载体负载纳米零价铁,制备FAP/nZVI（粉煤灰基纳米零价铁多孔材料）,以散失率、龙胆紫去除率、纳米零价铁负载量等为指标,确定FAP及FAP/nZVI的最佳制备条件,并考察二者对染料龙胆紫的去除特性.结果表明:① FAP的最佳制备条件为m（粉煤灰）:m（膨润土）:m（棕榈壳）=190:95:15,升温速率10℃/min,烧结温度800℃,保温时间30 min.② FAP/nZVI最佳制备条件为m（Fe）/m（FAP）1:3,振荡时间1 h,选用抗坏血酸为稳定剂,过程中无需使用惰性气体;SEM结果表明纳米零价铁被成功负载于FAP上.③ FAP/nZVI对200 mg/L龙胆紫的去除率为94.8%,FAP同条件下的去除率仅为26.2%,FAP/nZVI对龙胆紫的去除同时存在物理吸附和化学还原作用,并且纳米零价铁的还原占主导作用.④ FAP/nZVI再生10次后30 min内对100 mg/L龙胆紫去除率高达97.6%.研究显示,FAP可将纳米零价铁氧化产物Fe2+固定在表面,经还原后可再生为纳米零价铁,具有良好的再生性能.      

零价铁脱氯还原多氯联苯的研究进展

多氯联苯(PCBs)是环境中广泛存在的一种典型的持久性有毒有机污染物,对人类和环境产生了许多不利影响。近年来,零价铁技术作为化学修复PCBs污染介质的一种有效方法,具有较好的应用前景。文章综述了国内外应用零价铁技术对环境介质中PCBs污染物脱氯还原的研究进展,介绍了铁粉、纳米铁、铁钯双金属降解PCBs的反应以及影响因素的研究,指出了目前利用零价铁技术降解PCBs研究存在的问题,并对今后零价铁脱氯还原技术治理土壤或沉积物中PCBs污染物的实际应用提出了展望。     

零价铁/TiO_2去除水中三氯甲烷的实验研究

通过实验研究了零价铁(高碳铁屑)与TiO2对水中三氯甲烷去除率的共同作用规律。实验采用氯离子选择电极、气相色谱和扫描电镜分析方法,研究了相关材料及零价铁与TiO2比例,pH等条件对水中三氯甲烷去除率的影响规律:当铁屑与TiO2质量比为97:3、pH值为6.0时,水中三氯甲烷去除率最高;并采用相应的动力学模型进行了拟合分析以及对实验结果进行了分析和讨论。     

基于正交试验法的零价铁降解水环境中的氯代烃

氯代烃的生产和应用给环境水体带来的污染日益严重,可利用零价铁零价铁对其进行还原脱氯以达到去除的目的。本文采用正交试验法,将零价铁对氯代烃的去除率作为考察指标,研究pH值、零价铁粒径和振荡速率3个因素对氯代烃去除率的影响,结果表明:3个影响因素的重要性表现为pH值零价铁粒径振荡速率,且pH值具有极显著影响;最优水平下的零价铁对氯代烃具有较好的降解效果,且零价铁对TCE和PCE的降解符合准一级反应。     

零价铁用于水中氯代有机物还原脱氯的现状与发展

综述了零价铁作为氯代有机物的发展状况,零价铁、纳米零价铁、含铁双金属体系及固定态双金属体系还原脱氯机理、应用现状、存在问题及其未来发展趋势。     

微生态制剂使养殖零污染不再是梦

随着畜牧业的快速发展,畜禽养殖已经成为了我国农业领域第一污染大户,治理畜禽养殖污染业已迫在眉睫．     

冰川积雪融水补给为主河流水库蓄水期起始时间的判定

如何科学合理地确定水库蓄水期起始时间对保证水库正常运行、下游灌溉、供水、河道生态需水等方面有重要的作用,尤其是以冰川积雪融水补给为主的河流水库。而目前在实际水库运行中也没有一个较好的合理确定标准和方法,只能根据流域特性水库运行管理人员主观确定,受人为因素影响较大,增加了水库正常运行的不确定性,不能充分发挥水库各方面的效益。因此提出在以MOD IS积雪监测数据基础上结合零度层高度监测数据即雪线高度合理确定水库蓄水期起始时间的方法,更具有说服力及合理性,对水库运行管理提供了一定的指导依据,有利于当地水资源的合理利用,并通过实际应用说明方法是可行的。     

Treatment of simulated wastewater containing Reactive Red 195 by zero-valent iron/activated carbon combined with microwave discharge electrodeless lamp/sodium hypochlorite

A comparative study of treatment of simulated wastewater containing Reactive Red 195 using zero-valent iron/activated carbon (ZVI/AC), microwave discharge electrodeless lamp/sodium hypochlorite (MDEL/NaClO) and the combination of ZVI/ACMDEL/ NaClO was conducted. The preliminary results showed the two steps method of ZVI/AC-MDEL/NaClO had much higher degradation e ciency than both single steps. The final color removal percentage was nearly up to 100% and the chemical oxygen demand reduction percentage was up to approximately 82%. The e ects of operational parameters, including initial pH value of simulated wastewater, ZVI/AC ratio and particle size of ZVI were also investigated. In addition, from the discussion of synergistic e ect between ZVI/AC and MEDL/NaClO, we found that in the ZVI/AC-MEDL/NaClO process, ZVI/AC could break the azo bond firstly and then MEDL/NaClO degraded the aromatic amine products e ectively. Reversing the order would reduce the degradation e ciency.     

废弃线路板有价金属回收的物理处理工艺

线路板是绝大多数电子产品达到电路互连的不可缺少的主要组成部件,其中蕴合许多有价金属,如铜、铁、铝、锡、铅、金、银等,其回收方法以物理法为主。介绍了目前占主导地位的几种物理法回收技术及工艺流程,并且提出自己的湿法处理工艺。     

Coupling of zero valent iron and biobarriers for remediation of trichloroethylene in groundwater

This study attempted to construct a three series barrier system to treat high concentrations of trichloroethylene (TCE; 500 mg/L) in synthetic groundwater. The system consisted of three reactive barriers using iron fillings as an iron-based barrier in the first column, sugarcane bagasse mixed with anaerobic sludge as an anaerobic barrier in the second column, and a biofilm coated on oxygen carbon inducer releasing material as an aerobic barrier in the third column. In order to evaluate the extent of removal of TCE and its metabolites in the aquifer down gradient of the barrier system, a fourth column filled with sand was applied. Residence time of the system was investigated by a bromide tracer test. The results showed that residence time in the column system of the control set and experimental set were 23.62 and 29.99 days, respectively. The e ciency of the three series barrier system in removing TCE was approximately 84% in which the removal e ciency of TCE by the iron filling barrier, anaerobic barrier and aerobic barrier were 42%, 16% and 25%, respectively. cis-Dichloroethylene (cis-DCE), vinyl chloride (VC), ethylene and chloride ions were observed as metabolites following TCE degradation. The presence of chloride ions in the e uent from the column system indicated the degradation of TCE. However, cis-DCE and VC were not fully degraded by the proposed barrier system which suggested that another remediation technology after the barrier treatment such as air sparging and adsorption by activated carbon should be conducted.