农林废弃物吸附水体中重金属的研究进展

含有重金属的废水对环境、水生生物和人体健康等都产生了严重的影响。废水中重金属的处理方法有很多,用农林废弃物吸附水体中的重金属离子实现了“变废为宝、以废治废”的目的,有广泛的应用前景。介绍了农林废弃物吸附水体中重金属的机理及研究进展。     

生物吸附在含重金属废水处理中的研究进展

生物吸附法是目前处理含重金属废水最有前途的方法之一,尤其在处理含1~100mg/L的重金属废水时特别有效。详细介绍了生物吸附的机理、不同种类微生物对重金属的吸附特性,并对影响生物吸附过程的各种因素进行了讨论,最后对生物吸附重金属的发展方向进行了预测。     

吸附法处理重金属废水污染的研究进展

重金属在环境中只能迁移和转化,不能够被降解,因此重金属被排入到环境中以后,会严重破坏生态环境,对动植物和人体健康造成威胁。目前,重金属废水处理已成为急需解决的问题之一,为此需要合理应用现代化技术手段使其能够做到无害化排放,常见技术方法包括沉淀法、吸附法、电化学法、膜分离法等,其中吸附法因其耗资更少、操作简单,为此被广泛应用于重金属废水污染处理中,以此为后续领域发展提供帮助。通过吸附法处理重金属废水,最为关键的是得到高性能、低成本的吸附剂,本文对吸附法处理重金属废水的原理进行了分析,并且对吸附剂在处理重金属废水的研究进展进行了介绍,探讨吸附法处理重金属废水的机理,包括物理吸附、化学吸附和生物吸附三个部分,随后分析了重金属废水所用吸附剂,包括碳基吸附剂、纳米材料吸附剂、矿物吸附剂、高分子吸附剂以及生物吸附剂,切实提高重金属水污染的处理效果,以期能够为相关人员提供参考和借鉴。     

啤酒酵母对重金属离子生物吸附的研究进展

文章简要介绍了目前国内采用啤酒酵母生物吸附处理废水中重金属离子的研究状况,探讨了pH、温度、吸附时间、溶液初始浓度、共存离子等因素对啤酒酵母吸附重金属离子的影响。展望了啤酒酵母生物吸附重金属离子的发展趋势和应用前景。     

生物法处理重金属废水研究状况

在生物处理层面上介绍了3种治理重金属废水的方法,即生物吸附法、生物絮凝法、植物修复法,体现出了它在处理重金属废水中的重要性和应用前景。     

啤酒酵母在重金属废水处理中的应用

生物吸附法是一种新兴的水处理方法,具有处理效果好、资金投入少、适用范围广及可回收利用废水中的重金属等特点。啤酒酵母是一种廉价易得的生物吸附剂,目前在废水处理中已有应用。本文简单介绍了啤酒酵母在含镉废水、含铜废水、含铀废水及含铅废水处理中的应用情况。     

生物炭净化废水中重金属机理

生物质热解转化为生物炭用以去除废水中的重金属,可以同时起到固废资源化和废水处理的双重环境效益。文中阐述了生物炭净化废水中常见重金属(铅、镉、锌、铜、铬以及砷)的主要机制。生物炭可以通过离子交换、表面吸附、官能团络合以及形成沉淀等多种机制去除重金属,并对铅、镉、锌、铜以及铬都表现出一定的去除效果,而对重金属砷则去除效果较差,需通过改性处理提高对砷的作用。因此,文中同时介绍并总结了常见复合生物炭的设计原理,及其对重金属去除的强化效果。包括:(1)铁复合生物炭固定砷;(2)还原性铁复合生物炭还原稳定铬;(3)纳米颗粒复合生物炭吸附固定铅、镉、铜。生物炭以及复合生物炭用以去除废水重金属具有很好的效果与应用前景。最后,文中提出了生物炭净化废水在实际应用中面临的问题,未来的研究可以聚焦生物炭的标准化制备工艺,以及复合生物炭对重金属去除的实际应用。     

衣藻对重金属生物吸附的实验研究

以衣藻为生物吸附材料,研究了它对重金属钴、铜、锌的生物吸附,并用Freundlich等温吸附方程对实验数据进行处理。结果表明衣藻对这三种金属吸附能力大小顺序为锌钴铜;农藻对重金属的吸附能力很强,可用衣藻来处理含重金属的废水。     

生物吸附剂处理含重金属废水研究进展

如何消除重金属的危害并有效地回收废水中的贵重金属是环境保护工作面临的突出问题.生物吸附技术作为新兴的重金属去除技术,愈来愈受到人们的关注.介绍了生物吸附剂的种类特征,综述了生物吸附剂在处理方法、吸附机理、应用等方面的研究进展,同时阐述了生物吸附剂处理含重金属废水研究的发展趋势和应用前景.     

废棉纺织物制备生物炭材料及其对印染废水的应用

以废棉纺织物为研究对象,对其进行改性处理,分析原样和改性样的元素组成和表面形态,确定出废棉纺织物制备生物炭材料的方法,研究生物炭材料对亚甲基蓝印染废水的吸附特性。实验表明,棉纺织废物经改性后,表面形态呈现粗糙且疏松的结构;改性样生物炭的pH值为9.51时,生物炭中碳质量分数为67.5%,生物炭得率为43.2%,生物炭碘吸附值为2 493 mg/g,生物炭材料表面官能团非常丰富,具有吸附能力;当亚甲基蓝印染废水初始质量浓度为300、400 mg/L时,平衡吸附量为112.1、119.4 mg/g,吸附过程是快速吸附,吸附量大,有较好的吸附作用。废棉纺织物改性后可以促进生物炭孔结构的形成,具有吸附能力,为废纺织物的资源化利用、吸附剂的制备和印染废水的处理提供了一种新方法。     

用海藻类生物吸附剂去除废水中的重金属离子——一种经济型新技术

Heavy metal pollution from industrial wastewater is a worldwide environmental issue. Biosorption of heavy metals by using biosorbents derived from various types of biomass has been shown to be effective for the uptake of heavy metal ions. In this study, biosorbents derived from the biomass of a group of marine macroalgae were used for the removal and recovery of heavy metal ions from aqueous solutions. Results indicated that the biosorbents have high uptake capacities and affinities for a number of heavy metal ions. The uptake capacities of the biosorbents were in the range of 1.0 to 1.5mmol·g-1 for divalent heavy metal ions. The kinetics of the uptake process was fast and the process can be used in both batch and fixed-bed operations. It appears that the biosorption process by using biosorbents from marine macroalgae can be an efficient and cost effective technology for the treatment of heavy metal containing wastewater.     

Contribution of agro‐waste material main components (hemicelluloses,cellulose, and lignin) to the removal of chromium (III) from aqueous solution

BACKGROUND: Agro‐waste materials can be used as biosorbents of heavy metals in aqueous solution. However, it is necessary to further study the contribution of agro‐waste materials components (i.e. hemicelluloses, cellulose, and lignin) to the heavy metal ions removal from aqueous solution to better understand the biosorption mechanism, and also based on the biosorbents main components, to predict their potential to remove heavy metals. RESULTS: Cellulose is contained in major proportion (greater than 46%) in the agro‐waste materials reported herein compared with hemicelluloses (from 12% to 26%), lignin (varying from 3% to 10%), and other compounds (22% to 30%) that were removed after the neutral detergent fiber procedure. The identified functional groups in agro‐waste materials and their fractions included hydroxyl, carboxyl, and nitrogen‐containing compounds. Lignin contributed in higher proportion than hemicelluloses to Cr (III) adsorption capacity in both sorghum straw and oats straw. On the other hand lignin was the main fraction responsible for Cr (III) adsorption in agave bagasse. CONCLUSION: Hemicelluloses and lignin were the main contributors to Cr (III) removal from aqueous solution, and cellulose contained in the agro‐waste adsorbents studied did not seem to participate. Copyright © 2009 Society of Chemical Industry     

重金属的生物吸附

本文介绍了生物吸附重金属的原理及其应用研究现状。总结了生物吸附剂的来源及其预处理方法;对影响生物吸附过程的各种因素进行了讨论     

市政污泥生物质炭在废水吸附处理中的应用

随着经济全球化的飞速发展,城市污水处理中排放的污泥量日益增加,预计到2025年我国市政污泥年产量将超过9000万吨。市政污泥中含有的病原微生物、有机物及重金属,会对环境和人体健康造成严重危害。污泥衍生的生物炭材料因其较大的比表面积、优良的孔隙结构以及丰富的含氧基团,被广泛应用于废水吸附处理领域,实现了固体废物再利用和去除污染的双重目的,做到以废治废,达到生态与发展的双赢。本文系统总结了污泥生物质炭的制备及改性方法、综述了其对废水中重金属、染料、无机盐、抗生素、酚类等的应用及其吸附机理,指出未来污泥生物炭的发展方向和需攻克的难题,努力形成绿色低碳的资源化处理体系。     

反渗透技术在重金属废水处理与回用中的应用

许多工业生产过程中产生并排放大量的含重金属废水,这不仅严重污染环境,还造成资源浪费.采用反渗透技术处理重金属废水,设备紧凑,操作简单,特别是能够实现重金属的回收,符合清洁生产的原则,应用前景广阔.介绍了反渗透技术的原理、反渗透技术在重金属废水处理及回用中应用需注意的问题以及近年来的最新研究成果和应用实例,并展望了进一步研究的方向和发展趋势.     

啤酒酵母吸附去除水中Cd~(2+)的影响因素

生物吸附法是一种经济有效的处理大规模低浓度重金属废水的生物技术,其中啤酒酵母(Saccharomyces cerevisiae)是具有实用潜力的生物吸附剂。本文研究了啤酒酵母对Cd2+吸附效果的主要影响因素,结果表明pH值对Cd2+会产生较大的影响,非固定化和固定化啤酒酵母对Cd2+吸附的最佳pH值都为4,过高和过低均不利于吸附的进行。水中常见的K+、Ca2+、Na+、Mg2+四种离子在低浓度时对Cd2+的吸附无显著影响,但当其浓度高于5mg/L时会影响吸附,其影响顺序为K+Na+Ca2+Mg2+;Zn2+、Fe2+、Cu2+、Pb2+对Cd2+的吸附效果影响顺序为Pb2+Zn2+Fe2+Cu2+;当Cu2+浓度≥50mg/L时,啤酒酵母对Cd2+不产生性吸附,而对Cu2+产生专性吸附。     

Patent abstracts

This paper gives an overview of the feasibility of the application of biotechnology to nuclear waste treatment. The contents are based on a report which PA Technology carried out for the Department of the Environment (DoE Reference: DoE/RW/88.008 Sector No 2.3). Many living and dead organisms accumulate heavy metals and radionuclides. The controlled use of this phenomenon forms the basis for the application of biotechnology to the removal of radionuclides from nuclear waste streams. Indeed, biotechnology offers a series of new opportunities for removal of radionuclides from dilute aqueous process effluents. Such technology is already used for heavy metal removal on a commercial basis and could be optimised for radionuclide removal. An overview of biotechnology areas, namely the use of biopolymers and biosorption using biomass applicable to the removal of radionuclides from industrial nuclear effluents is given. The potential of biomagnetic separation technology, genetic engineering and monoclonal antibody technology is also to be examined. The most appropriate technologies to develop for radionuclide removal in the short term appear to be those based on biosorption of radionuclides by biomass and the use of modified and unmodified biopolymers in the medium term.     

The biosorption of Cr(VI) ions by dried biomass obtained from a chromium-resistant bacterium

The biosorption potential of many different kinds of biomaterials has been widely studied. However, there is little data on the biosorption mechanism of Cr(VI) by dried biomass. So the bio-removal of Cr(VI) ions from aqueous solutions was investigated using dried biomass from a chromium-resistant bacterium. The bacterium was isolated from dewatered sludge samples that were obtained from a sewage treatment plant. Equilibrium and kinetic experiments were performed at different metal concentrations, pH values, and biosorbents dosages. The biomass was characterized using scanning electron microscopy and energy-dispersive X-ray spectroscopy. The functional groups in the Bacillus cereus biomass which may play a role in the biosorption process were identified by Fourier transform infrared spectroscopy. The biosorption process was found to be highly pH dependent and the optimum pH for the adsorption of Cr(VI) was 2.0±0.3 at 30±2 °C. The experimental data fit well with Langmuir and Freundlich models as well as a pseudo-second order kinetic model. The mechanism for the biosorption was also studied by fitting the kinetic data with an intra-particle diffusion model and a Boyd plot. External mass transfer was found to be the rate-determining step for the adsorption process. Biosorption could be an alternative mechanism besides bio-oxidation and bio-reduction for the bioremediation of heavy metals.     

生物吸附剂及其在重金属废水处理中的应用进展

重金属离子严重危害人体健康,因此在废水处理中必须将其去除。传统去除重金属离子的方法很多,但都存在某些不足,近年发展起来的生物吸附技术,在水处理领域具有很好的应用前景。综述了近年来生物吸附剂在重金属废水处理中的应用情况,同时探讨了今后生物吸附法去除重金属的发展趋势。