改性锯屑对钙镁离子的吸附特性研究

研究用改性锯屑处理废水中钙锾离子的新方法,通过静态实验研究改性锯屑的吸附容量;通过动态试验研究了进水速度和浓度等因素对Ca2+、Mg2+吸附过程的影响以及探讨改性锯屑的吸附再生.实验表明,低流速和高浓度废水溶液对改性锯屑提高Ca2+、Mg2+吸附容量有利;用NaCl溶液可时吸附饱和的改性锯屑进行再生.     

重金属处理技术研究进展

重金属是水环境中的主要污染物之一,随着社会的进步和工业的发展,含重金属离子废水的排放量在逐渐增多,主要来自电镀、采矿、冶金、化工等工业,具有潜在的危害性.近些年来,处理重金属废水的技术发展迅速,吸附法因为速度快、操作简单、吸附材料来源广等优点被人们广泛应用,尤其是金属离子印迹技术.目前为止,已经成功制备出了以Ni2＋、Cu2＋、Cd2＋、Zn2＋等多种金属离子为模板离子的金属离子印迹聚合物,并在环境分析和医药领域有着广泛的应用.     

负载纳米氧化铁活性炭去除水中重金属铜实验研究

采用两种制备方法(M1、M2),分别对三种活性炭(AC1、AC2、AC3)进行负载纳米氧化铁实验研究.通过不同材料对Cu(Ⅱ)吸附量的筛选实验,得出AC2-M2对Cu(Ⅱ)吸附量最大.对AC2-M2进行的静态吸附实验研究结果表明:pH值在1~6范围内,AC2-M2对Cu(Ⅱ)的吸附量随pH值增大而增加;AC2-M2对Cu(Ⅱ)的吸附规律符合Langmuir吸附等温模型和准二级动力学模型,与AC2相比,其最大吸附量提升了约113%,其吸附过程分为快速吸附、慢速吸附、动态平衡三个阶段;AC2-M2对Cu(Ⅱ)的吸附是自发吸热过程,吸附机理主要以物理吸附为主,并同时存在化学吸附.     

谈生物淋滤去除污泥中重金属的方法

随着社会经济的不断发展,太原市污水排放量迅速增加,污泥产量也随之增加。土地利用是目前最有潜力的污泥处置方法,但是受到重金属的限制。针对太原市污泥中重金属的特性,摸索用生物淋滤去除重金属的方法。     

对燃煤重金属研究的文献综述

对煤中重金属的分布、在煤燃烧过程中的行为及利用吸附剂吸附单一重金属蒸汽进行了论述。综合分析了国内外研究热点，并在此基础上提出了尚待进一步研究的问题及实验解决方法。     

人工湿地生态系统去除污染物机理概述

人工构造湿地主要利用湿地中植物、微生物和基质之间的物理、化学和生物作用共同达到污水净化的目的。其主要机理为:植物根系形成网络,传递和释放氧,吸收一部分营养物质,为微生物提供生长场所,并提供好氧、厌氧条件。好氧微生物分解有机物成CO2和H2O,硝化细菌和反硝化细菌去除氮,聚磷菌去除磷。主要是生化反应,但各自需要一定的条件。同时还有吸附沉淀作用,但存在吸附饱和度。     

蛋壳碳酸钙的应用研究进展

蛋壳废料在世界范围内大量产生,我国废弃蛋壳的年产量在3.0×109kg以上,废蛋壳中含有丰富的钙质资源,是重要的生物基碳酸钙和氧化钙原料,具有安全、环保等优点,以其为原料可以制备系列精细化工产品。蛋壳作为一种重要的生物碳酸钙和氧化钙来源,是多种有机精细化学品和无机精细化学品的重要原料,可以用作催化剂、吸附剂、添加剂等。通过综述蛋壳碳酸钙在制备醋酸钙、丙酸钙、乳酸钙、葡萄糖酸钙、柠檬酸钙、丙酮酸钙、苹果酸钙、果汁钙、硫酸钙及过氧化钙等制备上的应用,对蛋壳的利用提出建议：一是加强规模化利用,将蛋壳资源集中起来,形成规模效应;二是加强系列化应用,形成以蛋壳为原料的系列深加工产业链,变废为宝;三是加强资源化研究,不断开拓蛋壳利用新领域和新途径,提高蛋壳利用的经济效益和社会效益。     

吸附剂对垃圾焚烧中重金属分布规律影响的热力学模拟研究

通过吉布斯自由能最小热力学平衡法模拟研究了垃圾焚烧过程中重金属As,Cr,Cd和Pb的迁移和转化规律;考察了焚烧温度、空气过量系数、吸附剂(CaO,Al2O3和SiO2)的添加等主要焚烧工艺参数对重金属迁移和转化的影响。研究结果表明,焚烧温度对As,Cr,Cd和Pb的迁移转化有较大的影响,当温度高于800℃,重金属主要以CrAsO4,AsO(g),CrO2,CdO,CdCl2(g)和PbCl2(g)等形态存在。空气过量系数对重金属迁移转化影响较小。吸附剂的添加对重金属有一定的捕集作用。CaO的添加有利于降低As,Cr,Cd的挥发性;Al2O3的添加对As的捕集有很好的效果,但对Cr,Cd和Pb的挥发性影响较小;SiO2的添加对Pb的捕集有很好的效果,但对As,Cr和Cd的挥发性影响较小。     

Langmuir方程Γ∞在被吸附的重金属量测定中的应用

为研究吸附剂吸附的原理和影响因素,采用数学建模和模拟方法对Langmuir方程的常量Γ∞进行了定量分析,发现吸附剂总表面积是影响吸附能力的主要因素,吸附剂吸附能力随总表面积增大而增大,随粒径减小而急剧增大,悬浮物颗粒的几何形态影响甚小。天然状态下,单位水体悬浮物含量的不同将导致总表面积的不同,进而影响被吸附重金属的量。总之,改变悬浮物颗粒表面都会影响试验精度。     

沼肥中重金属含量初步研究

采用青饲料和配合饲料饲喂生猪,对所产生的猪粪进行沼气发酵,测试和分析沼肥中主要重金属的含量,初步探索出沼肥中重金属含量的变化趋势.分析数据表明:配合饲料沼渣中砷、镉、铬的含量远高于青饲料沼渣,两者沼液中汞、铅的含量呈显著性差异.     

Immobilization of Heavy Metals and Phenol on Altered Bituminous Coals

Abstract

This article evaluates adsorption ability of the altered bituminous coals to remove heavy metals and/or phenol from aqueous solutions. As for heavy metals, copper (II), cadmium (II) and lead (II) cations were used. In addition to phenol, cyclohexanol and 2-cyclohexen-1-ol were also examined. Adsorption experiments were conducted in the batch mode at room temperature and at pH 3 and 5. To characterize the texture of coal samples, adsorption isotherms of nitrogen at ?196°C, enthalpies of the immersion in water, and pH values in aqueous dispersions were measured. Coal hydrogen aromaticities were evaluated from the infrared spectrometric examinations (DRIFTS). Based on the investigations performed, cation exchange was confirmed as the principal mechanism to immobilize heavy metallic ions on coals. However, apart from carboxylic groups, other functionalities (hydroxyl groups) were found to be involved in the adsorption process. During adsorption of phenol, π-π interactions between π-electrons of phenol and aromatic rings of coal proved to play the important role; however, no distinct correlation between adsorption capacities for phenol and hydrogen aromaticities of the coal was found. Probable involvement of oxygenated surface groups in the immobilization of phenol on coal was deduced. As a result, for waste water treatment, oxidative altered bituminous coal can be recommended as a suitable precursor, with the largest immobilization capacities both for metallic ions and phenol, as found in the studied samples.     

焚烧过程中氯对重金属形态的影响及脱氯特性研究

目前我国国内还普遍缺乏对危险废弃物焚烧处理的机理研究，尤其是焚烧过程中关于氯、重金属排放及二者之间关系的基础研究。从这一点出发，着重研究了典型危险废弃物之一染料残渣在小型管式炉中焚烧过程中氯化氢的排放特性；并利用化学热力学平衡方法计算了焚烧过程中氯元素对多种常见重金属的排放影响；初步研究了在利用回转窑处理危险废弃物时，两种脱氯剂对烟气中氯的脱除效果。     

采用螯合剂稳定垃圾焚烧飞灰中的重金属

介绍了螯合剂的结构特点、合成方式以及稳定重金属的原理,并分析了螯合剂在稳定焚烧飞灰等废渣方面的应用现状和我国目前螯合剂制备方面的技术现状,指出利用螯合剂稳定焚烧飞灰等废渣中重金属所存在的问题、障碍和解决的途径。     

危险废弃物焚烧中重金属迁移特性研究现状

针对我国的危险废弃物研究处于起步阶段,从危险废弃物的定义出发,对危险废弃物中重金属的来源、用焚烧法处理危险废弃物时重金属的迁移和转变特性及其影响因素等方面进行了详细介绍和分析,为帮助人们加深对危险废弃物处理和处置正确性和重要性的认识,进一步研究在焚烧中如何控制重金属的迁移问题提供参考。     

A review on sediment microbial fuel cells as a new source of sustainable energy and heavy metal remediation: mechanisms and future prospective

Sediment microbial fuel cells (SMFCs) are different from microbial fuel cells because they are completely anoxic and lack a membrane. SMFCs are a novel technology for the simultaneous production of renewable energy and bioremediation of heavy metals. Recently, SMFCs have attracted the attention of many researchers because of their moderate functioning parameters and ability to use a range of biodegradable substrates like glucose, glutamic acid, river water, cysteine, acetate, and starch. The inocula used in SMFCs include river sediment, marine sediment, and wastewater. For power generation, many exoelectrogens in SMFCs have the ability to transfer electrons from electrodes by using natural electron shuttles. Exoelectrogens use four primary pathways to transfer electrons to the electrodes, including short‐range electron transfer through redox‐active proteins, soluble electron shuttling molecules, long‐range electron transport by conductive pili, and direct interspecies electron transfer. The most dominant mechanism is long‐range electron transfer via conductive pili because pili have metal‐like conductivity. The powering by microbes is an emerging technique for the remediation of heavy metals from sediments. The pathways for transferring electrons in electrotrophs operate in the opposite direction from those in exoelectrogens. To further upgrade SMFC technology, this review targets the prototype, operating factors, working mechanisms, applications, and future perspectives of SMFCs. Copyright © 2017 John Wiley & Sons, Ltd.     

巯基功能化介孔硅的孔径调节及其吸附性能研究

叙述了以F127和CTMABr为模板剂,添加扩孔剂1,3,5三甲苯（TMB）经水热法合成不同孔径的巯基（-SH）修饰的新型介孔吸附剂。指出,以Cu＋2和Pb＋2为处理对象,根据不同孔径的介孔吸附剂对重金属离子的吸附性能,确定扩孔剂TMB投加量为TMB和表面活性剂摩尔比为1.5时,可得到重金属吸附的适用吸附剂的扩孔功能化硅基介孔材料,其BET孔径为6.554 nm,BET孔容为0.6134 cm3/g。     

Impact of heavy metals in Indian fly ashes on its application as soil ameliorant

Coal contains various organic and inorganic substances including trace quantities of the heavy metals. Therefore, the combustion of coals releases some of the ultimately to the environment of some heavy metals elements in the form of their oxides and in a redistribution of these heavy metals in the surface soil and water bodies, particularly in the vicinity of coal-fired power plants. The fly ash and pond ash of different thermal power stations of India were mixed with soil at different doses separately to compare their impact on crop produce and soil. The present study deals with the presence of the heavy metals in the coal ash and its movement through the amendment of coal ash to the soil and crop produce.     

土壤重金属污染治理的化学固化研究

伴随着我国社会经济的快速发展,我国的工业化进程也在不断的加快。当前,我国工业发展过程中大多数工厂都会排放大量含有重金属的污染物进入到自然环境之中,对我国自然环境中的土壤以及水源等造成很严重的危害。为了更好地解决工厂废弃物排放对环境的危害,对土壤重金属污染治理的化学固化研究方法进行了简要的分析。     

Hydrogen sorption in transition metal modified mesoporous materials

Ni, Rh and Pd incorporated mesoporous MCM-41, MCM-48, HMS and SBA-15 samples were synthesized and were characterized using XRD, ICP/EDX and N₂ adsorption–desorption at 77.4 K. The hydrogen adsorption studies in the synthesized materials were performed at 77.4 K (up to 112 kPa) and 303 K (up to 4000 kPa). The hydrogen adsorption isotherms of pristine and transition metals incorporated mesoporous materials at 77.4 K were completely reversible reflecting physisorption of hydrogen in these materials. The hydrogen adsorption isotherms at 303 K were not reversible showing the chemisorption of hydrogen in these materials at 303 K. Hydrogen sorption studies showed that transition metal modification improved the hydrogen storage capacity of mesoporous materials at 303 K. The desorption of the adsorbed hydrogen by heating up to 500 K from the mesoporous materials were also carried out for studying the recovery of adsorbed hydrogen from transition metal incorporated mesoporous materials.