稻谷重金属检测和去除方法的研究进展

现代工业快速发展导致部分稻谷污染了一定程度的重金属,解决稻谷重金属污染问题是保障粮食安全的重要内容。本文基于国内外的研究现状,首先总结比较了重金属检测方法的优缺点,其次总结了重金属在稻谷中的分布及存在形态,最后重点综述了对稻谷加工各个环节产物采取的重金属去除方法,展望了今后的研究方向,为重金属污染稻谷的合理利用提供借鉴。     

微生物法脱除重金属技术的研究进展

工业科技发展带来的负面问题——重金属污染问题日趋突出,严重威胁了生态环境平衡和人体健康,如何缓解重金属污染是目前环保领域关注的焦点问题之一。本文在简介物理、化学和生物法等脱除重金属技术的基础上,综述了生物法中的微生物法,总结了微生物法脱除重金属的显著优势。重点介绍了常见的微生物脱除剂,并分析其作用机理,探讨了国内外利用微生物法处理重金属的应用成果,最后展望了微生物法脱除重金属的未来发展趋势。      

食品中重金属检测与脱除技术研究进展

由于重金属在人体内的累积效应会产生潜在的健康危害,使得食品中的重金属脱除与检测技术越来越受到国内外学者的重视。文章对食品中重金属检测方法的原理及特点进行综述,并介绍几种主要的重金属脱除技术(浸泡法、化学法、吸附法、离子交换法等),同时对食品中重金属脱除技术的未来发展进行展望。     

食品中重金属脱除技术的最新研究进展

食品重金属污染问题屡见不鲜,重金属在人体内积累后,会严重损害人体的神经系统和肝肾功能。如何去除食品重金属污染,已成为当今世界范围内一个重要的食品安全问题。因此,开发食品中重金属脱除技术对于保障食品安全具有重要意义。常见食品中重金属脱除技术根据原理可分为物理处理法、化学浸提法、微生物法和吸附法等。近年来,食品中重金属脱除技术发展较快,尤其是在吸附法中出现了很多高效、绿色和选择性高的吸附材料。本文总结了食品中各类重金属脱除技术,重点介绍各种技术的研究新进展以及其优缺点,为食品中重金属污染物的脱除提供基础参考,同时有助于促进脱除技术的新发展,并为保障食品安全提供新思路。     

大米中重金属污染及其脱除技术研究进展

现代工业的快速发展,致使我国大米重金属污染问题日益严重。针对我国大米的生产和消费情况以及重金属的污染现状,综述了几种行之有效的重金属检测方法,并对目前大米中重金属污染的脱除技术进行了总结和分析,为今后治理大米中的重金属污染指明了研究方向。     

Combined removal of chlorinated ethenes and heavy metals by zerovalent iron in batch and continuous flow column systems

The combined removal of chlorinated ethenes and heavy metals from a simulated groundwater matrix by zerovalent iron (ZVI) was investigated. In batch, Ni (5-100 mg L(-1)) enhanced trichloroethene (TCE, 10 mg L(-1)) reduction by ZVI (100 g L(-1)) due to catalytic hydrodechlorination by bimetallic Fe0/Ni0. Cr(VI) or Zn (5-100 mg L(-1)) lowered TCE degradation rates by a factor of 2 to 13. Cr(VI) (100 mg L(-1)) in combination with Zn or Ni (50-100 mg L(-1)) inhibited TCE degradation. Addition of 20% H2(g) in the headspace, or of Zn (50-100 mg L(-1)), enhanced TCE removal in the presence of Ni and Cr(VI). Sorption of Zn to ZVI alleviated the Cr(VI) induced inhibition of bimetallic Fe0/Ni0 apparently due to release of protons necessary for TCE hydrodechlorination. In continuous ZVI columns treating tetrachloroethene (PCE, 1-2 mg L(-1)) and TCE (10 mg L(-1)), and a mixture of the metals Cr(VI), Zn(II), and Ni(II) (5 mg (L-1)), the PCE removal efficiency decreased from 100% to 90% in columns operated without heavy metals. The PCE degradation efficiency remained above 99% in columns receiving heavy metals as long as Ni was present. The findings of this study indicate the feasibility and limitations of the combined treatment of mixtures of organic and inorganic pollutants by ZVI.     

壳聚糖及其衍生物脱除贝类中重金属的机理及应用研究进展

海洋重金属污染问题已成为全球关注的热点。因具有较强的重金属富集能力,水产贝类鲜食及其加工产品的重金属超标问题亟待解决。壳聚糖是天然的碱性多糖,具有很强的重金属螯合能力,蕴含量也非常丰富。文章分析壳聚糖及其衍生物用于吸附及脱除重金属的分子结构特征与吸附作用机制;综述其在牡蛎、扇贝等主要经济贝类中的相关研究及应用,强调以生物吸附剂脱除并净化贝类重金属的重要性;对贝类重金属脱除研究提出建议,并展望其应用前景。     

石墨消解-电感耦合等离子体质谱法测定烟用香精中的重金属

[目的]优化和建立石墨消解-电感耦合等离子体质谱联用的方法测定烟用香精中的重金属.[方法]选择自主设计的新型消解罐,研究不同消化温度、不同消解液用量对样品消化的影响,将优化结果与微波消解-电感耦合等离子体质谱联用法对比检出限、定量限、加标回收率、RSD.并依据GB/T 27417—2017《合格评定化学分析方法确认和验...     

ICP-MS法测定纺织助剂中的重金属含量

以锑(Sb)、镉(cd)、铅(Pb)、铬(Cr)、钻(Co)、铜(Cu)、镍(Ni)、铁(Fe)、砷(As)重金属元素为对象,采用微波消解-电感耦合等离子体质谱(ICP-MS)法测定纺织助剂中的重金属含量.介绍了微波消解样品的程序和优化的ICP-MS工作参数.结果表明,微波消解-ICP-MS法适用于纺织助剂中多种重金属元素的快速测定,操作简便,准确度、灵敏度和回收率高,相对标准偏差<10%,加标回收率为88.2%～102.9%.     

核酸适配体检测食品中的重金属研究进展

近些年食品中重金属超标引发很多问题, 严重危害人民群众的生命健康和社会稳定。传统重金属检测方法有原子吸收光谱法, 原子荧光光谱法和X射线荧光光谱法等, 其具有检测灵敏度高, 选择性好, 检测方法成熟等优点, 但是也存在着检测仪器昂贵, 前处理复杂, 检测所需时间长, 不易携带, 不能满足快速、简单、现场测定的实际需要等不足。科研工作者一直在不断探索能够快速, 灵敏, 高效的检测重金属的技术。适配体具有特异性强, 灵敏度高, 稳定性好等优点, 已经成为一种新型识别分子, 被广泛应用于食品中重金属的检测。本文综述了近年来适配体在镉、汞、铅、砷等重金属检测领域的研究, 并对核酸技术在重金属检测方面进行展望。     

ELISA法快速检测食品中重金属含量的研究进展

重金属超标会对人体健康产生极大危害,世界各国日渐重视食品中重金属的限量标准,同时对重金属分析检测方法的研究也越来越多。传统的重金属检测方法比较成熟,灵敏度高,但操作繁琐、费用高昂、依赖大型仪器设备以及需要专业技术人员操作等。酶联免疫(enzyme-linked immune sorbent assay,ELISA)法是一种特异性强、灵敏度高的检测方法,并能用于现场快速检测,故得以迅速发展。ELISA法检测重金属主要包括四大关键步骤:样品前处理、人工抗原的合成、特异性抗体的制备、ELISA方法的选择。该文主要综述了ELISA法在检测重金属方面的最新研究成果,并对该检测技术的研究方向进行了展望。     

Application of beech sawdust for removal of heavy metals from water: biosorption and desorption studies

In this work the efficiency of applying non-modified beech sawdust for the removal of Cu²⁺ and Cr³⁺ heavy metal ions from water solutions was examined. Parameters taken into consideration in the analysis of environment conditions were influence of sorbent concentration, initial concentration of metal ions, temperature effect, presence of additional substances in solution (NaCl and MgCl₂ inorganic salts and anionic and cationic surface-active compounds). Results of kinetic experiments were described by two models: pseudo-first-order and pseudo-second-order; equilibrium results were approximated with five non-linear isotherm models. Maximum sorption capacity at a temperature of 20 °C and pH 5.0 was 30.22 mg g^?1 for Cu²⁺ ions and 41.86 mg g^?1 for Cr³⁺ ions. The positive value of the thermodynamic parameter ΔH° indicates the endothermic nature of the process. Application of 0.1 M HCl as the eluent enables effective desorption of precious metals and reuse of sorbent for purifying water solutions of Cu²⁺ and Cr³⁺ ions.     

微波消解原子吸收法测定蛤蜊重金属

优化出最佳测定务件及基体改进剂,测定蛤蜊中重金属元素.以微波消解样品,石墨炉原子吸收法测定Pb、Cd,火焰原子吸收法测定Mn、Cr,并进行了方法的准确性和精密度考察.结果表明:在试验浓度范围内,各元素的线性关系良好(r:0.9990～0.9999),方法的加标回收率(n=3)在93.6%～115.6%之间,RSD小于5%.该方法的精密度和准确性良好,可以用来进行海产品的质量控制和安全评价.     

Removal of heavy metals from mine waters by natural zeolites

In this study, we investigated the removal of Fe, Pb, Cd, and Zn from synthetic mine waters by a natural zeolite. The emphasis was given to the zeolite's behavior toward a few cations in competition with each other. Pb was removed efficiently from neutral as well as from acidic solutions, whereas the uptake of Zn and Cd decreased with low pH and high iron concentrations. With increasing Ca concentrations in solution, elimination of Zn and Cd became poorer while removal of Pb remained virtually unchanged. The zeolite was stable in acidic solutions. Disintegration was only observed below pH 2.0. Forward- and back-titration of synthetic acidic mine water were carried out in the presence and absence of zeolite to simulate the effects of a pH increase by addition of neutralizing agents and a re-acidification which can be caused by subsequent mixing with acidic water. The pH increase during neutralization causes precipitation of hydrous ferric oxides and decreased dissolved metal concentrations. Zeolite addition further diminished Pb concentrations but did not have an effect on Zn and Cd concentrations in solution. During re-acidification of the solution, remobilization of Pb was weaker in the presence than in the absence of zeolite. No substantial differences were observed for Fe, Cd, and Zn immobilization. The immobilization of the metals during pH increase and the subsequent remobilization caused by re-acidification can be well described by a geochemical equilibrium speciation model that accounts for metal complexation at hydrous ferric oxides, for ion exchange on the zeolite surfaces, as well as for dissolution and precipitation processes.     

荧光光度法测定汞及其它重金属离子研究进展

从汞的分离富集出发，按测定方法分类，对近来国内外有关汞的形态分析方法特别是荧光分析法的研究进展进行了综述。     

Coating Fe3O4 magnetic nanoparticles with humic acid for high efficient removal of heavy metals in water

Humic acid (HA) coated Fe3O4 nanoparticles (Fe3O4/HA) were developed for the removal of toxic Hg(II), Pb(II), Cd(II), and Cu(II) from water. Fe3O4/HA were prepared by a coprecipitation procedure with cheap and environmentally friendly iron salts and HA. TOC and XPS analysis showed the as-prepared Fe3O4/HA contains approximately 11% (w/w) of HA which are fractions abundant in O and N-based functional groups. TEM images and laser particle size analysis revealed the Fe3O4/HA (with approximately 10 nm Fe3O4 cores) aggregated in aqueous suspensions to form aggregates with an average hydrodynamic size of approximately 140 nm. With a saturation magnetization of 79.6 emu/g, the Fe3O4/HA can be simply recovered from water with magnetic separations at low magnetic field gradients within a few minutes. Sorption of the heavy metals to Fe3O4/HA reached equilibrium in less than 15 min, and agreed well to the Langmuir adsorption model with maximum adsorption capacities from 46.3 to 97.7 mg/g. The Fe3O4/HA was stable in tap water, natural waters, and acidic/ basic solutions ranging from 0.1 M HCl to 2 M NaOH with low leaching of Fe (< or = 3.7%) and HA (< or = 5.3%). The Fe3O4/HA was able to remove over 99% of Hg(ll) and Pb(ll) and over 95% of Cu(II) and Cd(II) in natural and tap water at optimized pH. Leaching back of the Fe3O4/HA sorbed heavy metals in water was found to be negligible.     

流动注射与火焰原子吸收联用测定食品中重金属的研究进展

流动注射分析法与火焰原子吸收光谱法联用测定食品中痕量重金属是一种快速、高效、简便的方法,现已被广泛应用在各种化学检测实验中。文中主要综述了近年来利用流动注射分析法与火焰原子吸收光谱法联用检测食品中重金属的研究进展,对各种方法的原理、应用范围、优缺点等进行了归纳和分析比较,并且探讨了流动注射分析法与火焰原子吸收光谱法联用测定食品中重金属的应用前景。     

微波萃取-ICP-AES测定纺织品中的重金属元素

为降低检测成本和缩短检测时间,以微波萃取法提取纺织品中的可萃取重金属元素,并结合ICP-AES测定重金属元素的含量.结果表明,在样品质量为1.0 g,汗液体积20 mL,40℃微波萃取20 min的条件下,各重金属元素的线性相关系数为0.9949～0.9999,方法检出限在0.01～0.17 mg/kg,加标回收率为8...     

脱除重金属的技术方法

人类对重金属的开采、冶炼、加工日益增多,造成不少重金属如铅、汞、镉、钴等进入大气、水、土壤中,引起严重的环境污染,进而对生物体造成巨大危害。因此,利用各种技术方法脱除其中的重金属是各行业都要解决的问题。文章主要介绍了用以处理污水、污泥、瓜果蔬菜、中药、水产品、果汁、植物等的重金属脱除法,包括化学沉淀法、吸附法、离子交换法等。此类方法在水产品的研发有着极其重要的作用,也为海洋食品加工利用中重金属的脱除提供了有用的参考。