Identification of chlorinated sulfur compounds in pulp mill effluents by GC-MS and GC-AED

Summary Three chlorinated dimethyl sulfones and five chlorinated thiophenes have been identified in the alkaline extraction liquor from a bleach plant by gas chromatography with atomic emission detection (GC-AED) and with mass spectrometry (GC-MS). The information on elemental content obtained by GC-AED enabled a rapid screening of the sulfur compounds and provided important structural information complementary to the mass spectral data. Quantitation was accomplished by GC-AED based on universal calibration.     

Flotation-spectrophotometric method for the determination of mercury using iodide and brilliant green

This paper describes a sensitive spectrophotometric method for the determination of mercury, based on the flotation of a mercury iodide-brilliant green complex with cyclohexane at pH 5 and dissolution of the complex in acetone. The absorbance of the complex is measured at 625 nm. Beer's law is obeyed from 4–500 g/l of mercury. The method is highly sensitive ( = 5.96 × 10⁵ 1 mol^–1 cm^–1) and selective, as it is free from interferences by almost all cations and anions in the presence of EDTA. Furthermore, a two-level orthogonal array design as a chemometric method has been used for optimization of the various parameters involved. The method has been successfully applied to paper industry effluents.     

Chemical Characterization of Silage Effluents and their Influence on Soil Bound Heavy Metals

Abstract

Silage effluents, generated during silaging of various crops, are produced in high amounts in cattle breeding farms. Due to their acidity and high content of dissolved organic matter, they are causing disposal problems. On the other hand, their ability to mobilise soil bound trace elements (i.e. heavy metals) might be useful for the decontamination of polluted soils.

With an aim to perform metal leaching studies, silage effluents from various ensiled crops (maize, rape, grass, clover, sugar-beet leaves) were collected from Bavarian farms and analysed for their main inorganic and organic constituents. Important TOC sources (TOC concentrations from 13.9 to 53.6 gl^?1) are short chain aliphatic acids (concentrations between 235 and 638 mM·D1^?1; predominant compound: lactic acid), amino acids (ranging from 22.8 to 151 mM·D1^?1) and polypeptides (concentrations from 3.8 to 20.0 g·D1^?1).

The release of heavy metals from two adsorbents (bentonite and peat) and from a polluted soil under the influence of silage effluents was studied in batch tests. The leaching efficiencies for the soil bound metals increase following the order: sugar-beet leaves < clover < maize < rape < grass. The extraction rates obtained with grass silage juice are: Cd 74.7%, Zn 55.7%, Cu 53.5%, Ni 38.9%, Cr 12.7% and Pb 8.9%. After neutralisation the leaching rates dropped, with the exception of copper.     

Third Order Derivative Spectrophotometry Determination of Mercury (II) as the Ternary Complex with Iodide and Pyronine G

Abstract

This paper describes a third order derivative mole cular absorption spectrophotometric procedure for the deter mination of traces of mercury based on the formation of ternary ion-association complex by reaction of mercury with pyronine G in the presence of iodide. The pink coloured ternary ion-association complex is readily formed in the pH range 1–7 and remained stable for 24 h. after stabilization with gelatin. The influence of various instru mental parameters and reaction conditions for maximum color development are discussed. The few interfering ions can be masked by the addition of appropriate reagent solutions.     

Environmental Determination of Alkylphenol Polyethoxylate Refractory Residues Using Mass Spectrometric Techniques

Abstract

The use of methane chemical ionisation GC/MS gave satisfactory results when applied to environmental analysis of halogenated octylphenol polyethoxylates residues. In addition the selected ion monitoring GC/MS technique has been successfully applied for simulataneous qualitative and quantitative determination of some refractory metabolites of nonylphenol polyethoxylates in secondary sewage effluent and surface waters.     

Remediation of azo-dyes based toxicity by agro-waste cotton boll peels mediated palladium nanoparticles

The present study reports an environmental benign route for the synthesis of palladium nanoparticles (Pd NPs) using agro-waste empty cotton boll peels aqueous extract for the first time. Surface Plasmon Resonance (SPR) band in absorption spectrum of Pd NPs at 275 nm confirmed the formation of Pd NPs by using UV–Vis spectroscopy. Crystalline nature of Pd NPs was confirmed by powder XRD analysis. Size and morphology was studied by transmission electron microscopy (TEM). The cotton peels extract acted as a source of phytochemicals which primarily reduced Pd⁺² to Pd⁰ nanoparticles (Pd NPs) and imparted stability of Pd NPs by surface capping. The characteristic functional groups of phytochemicals in extract and capped Pd NPs surfaces were identified by FT-IR analysis. Catalytic activity of the synthesised Pd NPs was checked against reduction of hazardous azo-dyes such as Congo red, Methyl orange, Sunset yellow and Tartrazine with NaBH₄ as electron donors. Pd NPs catalysed reduction of all azo-dyes by NaBH₄ in aqueous medium was monitored by UV–visible spectroscopy where Pd NPs mediated transfer of electrons from NaBH₄ to azo-dyes as carrier. The synthesized Pd NPs acted as a good catalyst and could be a promising material in degrading toxic azo-dyes from industrial effluents and wastewater.     

Quenchofluorimetric Determination of Mercury Trace with Murexide

 A sensitive and fairly selective quenchofluorimetric method for the determination of mercury ultra-trace with murexide (ammonium purpurate) has been developed. The method is based on the instantaneous quenching action of the metal-ion upon the native fluorescence of murexide [λ_ex(max) = 360 nm; λ_em(max) = 445 nm] in the optimum pH range of 5.8 to 6.6 at room temperature (25±0.5) °C. The fluorescence quenching is collinear in the range of 5 μg/L to 100 μg/L mercury. The developed method is very precise and accurate (RSD = 2.2% for 11 determination of 50 μg/L Hg(II). Large excesses of more than 50 cations, anions and complexing agents were found to have no interference. The developed method was successfully tested over synthetic mixtures of various compositions, certified reference materials and factory effluents. Received November 16, 1999. Revision March 30, 2001.     

Rapid automated screening, identification and quantification of organic micro-contaminants and their main transformation products in wastewater and river waters using liquid chromatography-quadrupole-time-of-flight mass spectrometry with an accurate-mass database

In this study we have developed and evaluated an analytical method for a rapid automated screening and confirmation of a large number of organic micro-contaminants (almost 400) and also the quantification of the positive findings in water samples of different types (surface and wastewaters) using liquid chromatography-electrospray quadrupole-time-of-flight mass spectrometry (LC-QTOFMS) based on the use of an accurate-mass database. The created database includes data not only on the accurate masses of the target ions but also on the characteristic in-source fragment ions, isotopic pattern and retention time data. This customized database was linked to commercially available software which extracted all the potential compounds of interest from the LC-QTOFMS raw data of each sample and matched them against the database to search for targeted compounds in the sample. The detailed fragmentation information has also been used as a powerful tool for the automatic identification of unknown compounds and/or transformation products with similar structures to those of known organic contaminants included in the database. The database can be continually enlarged. To confirm identification of compounds which have no fragment ions (or fragments with low intensity/relative abundance) from in-source CID fragmentation or isomers which are not distinguished within full single mass spectra, a "Targeted MS/MS" method is developed. Thereafter, these compounds can be further analyzed using the collision energy (CE) in QTOF-MS/MS mode. Linearity and limits of detection were studied. Method detection limits (MDLs) in effluent wastewater and river waters were, in most cases, lowers or equal to 5 and 2 ng/L, respectively. Only 15 compounds had MDLs between 5 and 50 ng/L in effluent wastewater matrix. We obtained a linearity of the calibration curves over two orders of magnitude. The method has been applied to real samples and the results obtained reveal that most of the pharmaceutically active compounds contained in the created database were present in the water samples with concentrations in the range of ng/L and μg/L levels and in most of the samples between 2 and 15 pesticides of the 300 contained in the database were also detected. In addition to the compounds included in the database, some degradation products were found, thus revealing the method as a useful tool for the analysis of organic micro-contaminants in waters.     

应用FTIR和~(13)C NMR表征制革废水处理过程的溶解性有机物特性

制革业是我国重要的工业门类,年废水排放量2亿t以上。制革废水中油脂、皮屑、胶原蛋白等大分子有机物含量较高,同时兼具高盐、高碱、高负荷的特点,已被相关部门列为重点监控的工业污染源。在制革废水的处理方面,不仅要关注进出水的水质参数,同时也要监测废水处理过程污染物的转化规律,以便为废水处理工艺的优化和废水处理设备的研发提供基本数据。溶解性有机物(DOM)广泛存在于各类水体中,是表征废水理化性质和净化程度的重要参数。目前,对于制革废水处理过程DOM性质的研究尚很欠缺。以此为切入点,采用元素分析、热重分析、红外光谱和核磁共振表征制革废水不同处理工段的DOM样品。研究发现:制革废水处理时间的延长导致DOM中C元素含量升高,H/C原子比先增加后降低,说明大分子有机物首先被分解为小分子链状结构,最终存在于水体的是极难降解的终极结构组分。DOM脂肪族化合物和蛋白组分的热解发生在第二阶段(110~530℃),第三阶段(530~800℃)主要完成芳环的降解或C—C键的断裂。废水原水DOM主要含有—OH,—NH2,CO等官能团,FTIR图谱证明了废水处理中后期高聚合度芳香族物质的存在,这是微生物新陈代谢作用的结果。DOM中烷基C含量先增加后减少,含量最大值(25.25%)出现在二级生化池;芳香C含量的最小值(28.28%)出现在二级生化池,而后迅速上升,暗示了废水处理过程含C官能团种类和数量的交替变化规律。对制革废水DOM性质的跟踪识别有助于从总体上推断污染物的净化机制。     

Removal of Radionuclides from Fukushima Daiichi Waste Effluents

This paper describes the processes used at the Fukushima Daiichi plant, Japan, to purify the waste effluents generated in the cooling of damaged reactors. These include primary cesium removal with the Kurion zeolite system and the SARRY system utilizing silicotitanate to remove radiocesium from water recirculated to reactors for cooling. Another process is the ALPS system to purify the retentates of the reverse osmosis plant to further purify the water from radionuclides after primary cesium separation. In ALPS, a major role is played by the transition metal hexacyanoferrate product CsTreat and sodium titanate SrTreat in the removal of radiocesium and radiostrontium, respectively. The performance of these four exchangers (zeolite, silicotitanate, hexacyanoferrate, and sodium titanate) is critically analyzed with respect to processing capacities and the decontamination factors obtained in the processes. Furthermore, general information on preparation, structure and ion exchange of these ion-exchanger categories is given with additional information on their use in nuclear waste effluent treatment processes. Finally, the importance of selectivity and associated factors are discussed.