Size and phase fractionation of water components by membrane filtration Distribution patterns for arsenic, iron and manganese in aqueous effluents of tin ore settling plant

The possibility of on-line membrane size-fractionation of water components and simultaneous separation of particulate and dissolved matter at each filtration stage has been shown. The distribution patterns have been studied for As, Fe and Mn in effluent samples of tin ore tailings (Altenberg, Saxony, Germany). The seepage composition is characterized by high concentrations of Fe and As. The particulate and dissolved components were separated in five fractions between 0.025 and 8 μm. It was suggested that the distribution patterns of As and Fe compounds depend on the chemical conditions at the sampling sites. Manganese exists mainly in solvated forms in the liquid fractions.     

Levels and patterns of polychlorinated biphenyls in water collected from the San Francisco Bay and Estuary, 1993–95

Levels of polychlorinated biphenyls (PCBs) were measured in water (particulate and dissolved fractions) from various locations in the San Francisco Estuary over the years 1993–1995 during six cruises. Geometric mean levels of ΣPCBs (sum of 58 congeners) in the combined dissolved and particulate fractions for the six cruises ranged from 340 ng/L to 1600 ng/L. Comparing this data to previous data from 1975 and 1980 does not reveal any significant temporal trends. The partitioning of PCBs into the dissolved/particulate fraction were correlated with total suspended solids. Using the novel chemometric technique of polytopic vector analysis (PVA) on the data from cruise 8 (April 1995), five separate PCB congener fingerprints were identified in the data. Fingerprint 1 (or end-member 1) represents a slightly degraded source of Aroclor^? 1260 in the northern part of the South Bay; the end-member (EM) 2 fingerprint is related to a predominantly Aroclor^? 1260 source that has been moderately-severely degraded present in the highest proportions in the Pacific Ocean sample; EM-3 is interpreted as a slightly degraded Aroclor^? 1242:1254:1260 mixture in southern San Pablo Bay; end-member 4 is interpreted as a moderately degraded source of multiple Aroclors^? and is present in the river samples; EM-5 is interpreted as a slightly degraded Aroclor^? 1254/1260 mixture present in northern San Pablo Bay and the South Bay. Received: 21 March 1997 / Revised: 23 May 1997 / Accepted: 28 May 1997     

Distributions of major-to-ultratrace elements among the particulate and dissolved fractions in natural water as studied by ICP-AES and ICP-MS after sequential fractionation.

In order to elucidate the distributions of the elements among the particulate and dissolved fractions in pond water, major-to-ultratrace elements in different sizes of particles as well as in the filtrate passed through the 0.05 microm filter were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES) and inductively coupled plasma mass spectrometry (ICP-MS). The different sizes of particle samples (ca. 100-300 microg each) were collected on the membrane filters with pore sizes of 10, 3.0, 1.2, 0.4, 0.2 and 0.05 microm, respectively, by sequential fractionation. As a result, about 40 elements in different sizes of particles could be determined by ICP-AES and ICP-MS, after acid digestion using HNO3/HF/HClO4. Then, the fractional distribution factors of major-to-ultratrace elements among the particulate and dissolved fractions were estimated from the analytical results. The total contents of Al, Fe, Ti, REEs (rare earth elements), Bi, Pb and Ag in the particulate fractions (larger than 0.05 microm) were more than 80-90%, while those of Ca, Sr, Cs, W, Ba, Mn and Co in the dissolved fraction, which corresponded to the filtrate passed through the 0.05 microm membrane filter, were more than 80%. It was further found that the fractional distributions of Cu and Zn in the dissolved fraction were ca. 50%. In addition, the enrichment factors (EFs) of the elements in the particulate fractions with particle sizes of 3.0-10 microm and 0.05-0.2 microm were estimated to elucidate their geochemical characteristics in natural water.     

Levels and patterns of polychlorinated biphenyls in water collected from the San Francisco Bay and Estuary, 1993–95

Levels of polychlorinated biphenyls (PCBs) were measured in water (particulate and dissolved fractions) from various locations in the San Francisco Estuary over the years 1993–1995 during six cruises. Geometric mean levels of ΣPCBs (sum of 58 congeners) in the combined dissolved and particulate fractions for the six cruises ranged from 340?ng/L to 1600?ng/L. Comparing this data to previous data from 1975 and 1980 does not reveal any significant temporal trends. The partitioning of PCBs into the dissolved/particulate fraction were correlated with total suspended solids. Using the novel chemometric technique of polytopic vector analysis (PVA) on the data from cruise 8 (April 1995), five separate PCB congener fingerprints were identified in the data. Fingerprint 1 (or end-member 1) represents a slightly degraded source of Aroclor^® 1260 in the northern part of the South Bay; the end-member (EM) 2 fingerprint is related to a predominantly Aroclor^® 1260 source that has been moderately-severely degraded present in the highest proportions in the Pacific Ocean sample; EM-3 is interpreted as a slightly degraded Aroclor^® 1242:1254:1260 mixture in southern San Pablo Bay; end-member 4 is interpreted as a moderately degraded source of multiple Aroclors^® and is present in the river samples; EM-5 is interpreted as a slightly degraded Aroclor^® 1254/1260 mixture present in northern San Pablo Bay and the South Bay.     

Inter-annual variability in atmospheric input and partitioning of heavy metals in the Lagoon of Venice

Atmospheric bulk deposition of major and trace elements was measured at Venice from November 1995 to October 1997. Collection was carried out using polyethylene bulk passive samplers, samples being collected bi-weekly. In order to highlight the contribution of the atmosphere to water chemistry and particle budgets in the Lagoon of Venice, the geochemical composition (Si, Al, Ca, Mg, K, Na, Mn, Cr, Zn, Pb, Cd, Cu, As) of dissolved and insoluble bulk fractions was determined by AAS + ICP mass spectrometry. Great sample variability was found, with almost two orders of magnitude between maximum and minimum values for several metals. All fluxes in 1995/96 were 30% lower than in 1996/97, ranging from -3% (Ca) to -57% (Li), except for Zn, Cd and As. On the contrary, the solubility of all elements decreased during 1996/97. Partitioning between soluble and insoluble phases shows that Al, Cr, Fe and Si are mainly in the insoluble form, whereas for As, Ca, Cu, Mg, Na, Ni, K, Pb and Zn the dissolved fraction represents 50-90% of total input. The amount of particle load affects partitioning between dissolved and particulate, especially for Al and Pb. Seasonal variability was evident. The lowest pH values (approximately 5.2) were recorded in winter, causing an increase of solubility for all metals except for As, which showed the highest solubility in summer.     

Size distribution and characteristics of chemical components in ambient particulate matter.

Ambient particulate matter and gas in Kyoto were investigated by gravimetric analysis, X-ray fluorescence spectrometry, and ion chromatography in order to clarify their behavior and origin. The size distribution and characteristics of the chemical components in ambient particulates collected on PTFE membrane filters using an Andersen air sampler were examined from August 2001 to April 2004. A four-stage filter pack method was used to sample the atmosphere for the determination of gas (SO2, HNO3, HCl, NH3) and particulate matter (SO42, NO3, Cl-, Na+, K+, Ca2+, Mg2+, NH4+) concentrations from October 2002 to April 2004. The concentration of SPM mass was in the range of 6.7 - 80.2 microg/m3. The size distributions of SPM mass were bimodal, peaking at around 0.65 - 1.1 and 3.3 - 4.7 microm, and 40 - 85% of SPM mass was fine particles (< 2.1 microm). Na, Mg, Al, Si, Ca, Cl, and Fe were mainly present in coarse particles (2.1 to 11.0 microm), while S was present in fine particles. The concentrations of Al, Si, Ca, Mg, and Fe in fine particles increased from March to April in 2002, and those in coarse particulates increased in November 2002 and from March to April in 2004. This may be the effect of the continental yellow sand "Kosa." The differences in the size distributions of Al, Si, Ca, Mg, and Fe in particles may depend on differences in their place of occurrence and course of transport from China to Japan. The concentration of HCl gas was higher than that of particulate chloride ion in summer. Nitric acid gas existed at higher concentrations in summer, but fine particulate nitrate ion was observed in winter. The gaseous-to-fine aerosol nitrate fraction became higher at warmer temperatures. Coarse sulfate was below 10%, and SO2 gas and fine particulate sulfate were above 90%.     

Distribution of Heavy Metals in Water and Soil Solutions Based on Colloid-Size Fractionation

The distribution of heavy metals Cr, Ni, Zn, Cu, Cd, and Pb among the truly dissolved (molecular weight cutoff <1 kD), colloidal (1 kD-0.20 µm and 0.20-0.45 µm) and particulate (>0.45 µm) fractions was investigated in the soil solution and surface water. In 15 soil solutions heavy metals were mainly present in the truly dissolved fraction (<1 kD) with occasional exceptions. And a good correlation was also found between the concentrations of metals in the truly dissolved fractions and the cation exchange capacity of soils. As for the surface water samples, the distribution pattern was more complicated one depending on metal properties and sampling sites.     

Chemiluminescence flow system for the determination of Fe(II) and Fe(III) in water

A novel chemiluminescence (CL) flow system has been developed for the sequential determination of Fe(II) and Fe(III) in water. Fe(II) was detected by its catalytic effect on the CL reaction between luminol immobilized on an anion exchange resin column and dissolved oxygen; Fe(III) was determined by difference measurement after on-line conversion to Fe(II) in a reducing mini-column packed with Cu plated Zn granules. For both ions, the calibration graph was linear in the range 1 × 10^–9 to 1 × 10^–6 g/mL, and the detection limit was 4 × 10^–10 g/mL. A complete analysis could be performed in 1.5 min with a relative standard deviation of less than 5%. The system could be reused for over 200 times and has been applied successfully to the determination of Fe(II) and Fe(III) in natural water samples. Received: 13 March 1997 / Revised: 3 June 1997 / Accepted: 6 June 1997     

Chemical characterization of selected metals by X-ray fluorescence method in particulate matter collected in the area of Krakow, Poland

This study presents the results of year long (2007–2008) particulate matter collecting campaigns. The three particle size fractions of particulate matter were collected in Krakow, Poland. Fine fraction consists of particles of a diameter below 2.5 µm, medium is between 2.5 and 8 µm and coarse fraction contains particles above 8 µm. Elemental concentrations were evaluated for each sample. Following elements were measured by EDXRF method: K, Ca, Ti, Cr, Mn, Fe, Cu, Zn, Br, and Pb. During each sampling campaign meteorological parameters such as temperature, wind speed, wind direction, humidity were taken from the same place. The highest values of mass particulate matter showed results from January 2008 and April 2008. These were about 14 µg/m³ for fine fraction, 8 µg/m³ for medium and 16 µg/m³ for coarse fraction. The lowest values were observed in May 2007, they were 4, 6, 6 µg/m³, respectively. During the winter season the wind speed was low and particulate matter remained in the air in high concentrations. In May 2007 the speed of wind was higher, reaching 2–3 m/s. PM was blown away from the city from the direction of N–W. Measured concentrations of elements were low, they were below permissible values specified by EU. The coarse fraction concentrations of Ca, Mn, and Fe were higher and characterized by the same trend. These samples were collected when the wind speed was low and its direction was from south-east. As concentrations of Cr, Cu, and Zn were low, these elements did not come from the south-east direction of Krakow. Concentration of Br correlates to the concentration of Pb. It suggests that they came from the same source (vehicles fuels burning).     

Field method for the micro-quantitative determination of tetracycline in human urine

A simple, fast and sensitive titrimetric method has been developed for the determination of tetracycline hydrochloride in human urine using m-dinitrobenzene as color agent and Dowex 1 × 8 as detection medium. Received: 26 February 1997 / Revised: 23 April 1997 / Accepted: 29. April 1997     

Assessment of Organic Source Contributions in Coastal Waters by Principal Component and Factor Analysis of the Dissolved and Particulate Hydrocarbon and Fatty Acid Contents

Abstract

Principal component (PCA) and factor analysis (FA) are evaluated for the interpretation of the information contained in large datasets resulting from the study of environmental samples by gas chromatography (GC) and GC coupled to mass spectrometry (GC-MS). A case involving the identification and quantitation of 64 variables (hydrocarbons and fatty acids) in 87 water samples (dissolved and particulate fractions) of a coastal system (Ebre Delta) has been selected for examination.

PCA has evidenced important differences between the dissolved and particulate materials, as well as between the particulates collected in the bays and those obtained in the river and channels. PCA has also allowed the identification of outlier samples in the dissolved fraction. Independent application of FA to each of these groups has provided a useful method for the characterization of diverse algal, terrestrial, microbial and anthropogenic inputs. Direct correspondences between these source inputs and factor loadings have provided a selection of representative components of each contribution in the coastal system.     

Chemical fractionation of a fly ash sample by a sequential leaching method

A five-stage sequential leaching procedure was optimized for the analysis of the fly ash sample, CW6, as a candidate reference material. The distribution of particulate elements was achieved for Cd, Cr, Cu, Pb, Zn, and V into different fractions: (1) exchangeable, (2) bound to carbonate, (3) bound to Fe/Mn oxides, (4) bound to sulfide compounds, and (5) acid soluble, residual fraction. The leachability of the metals proved to be different, so various distribution patterns have been achieved. The results of the total elemental analysis and the sequential leaching method were compared and a good agreement was found. The uncertainty of the leaching method is reasonable, even when experimental parameters are strictly fixed and the analysis is quite tedious. The ratio of environmentally mobile fractions was compared to that from the conventional test method and a reasonable conformity has been found. This characterization method can be used to interpret the leaching behavior of element species and mode of binding to the matrix. Using the optimized sequential procedure, a new aspect can be interpreted to understand the behavior of toxic elements released from fly ashes into nature.     

Elemental analysis of airborne dust samples with TXRF: Comparison of oxygen-plasma ashing on sapphire carriers and acid digestion for sample preparation

The concentrations of 13 elements (As, Ca, Co, Cd, Cr, Fe, Ga, Ni, Pb, Pt, Ti, V and Zn) were determined in air particulate matter using total reflection X-ray fluorescence spectrometry (TXRF). For silicon analysis synthetic sapphire was chosen as a new sample carrier material – it is silicon-free, resistant to oxygen-plasma, microwaves and concentrated acids. The dust samples were collected on cellulose acetate filters. The decomposition of the filters was carried out by oxidation in a microwave-generated low-pressure oxygen-plasma directly on the TXRF sample carriers. The recovery of the investigated elements was verified with the standard reference material SRM 1648 (urban particulate matter) and ranged from 90 to 97%. The oxygen-plasma method was compared with conventional sample preparation by acid digestion. Received: 9 April 1999 / Revised: 18 May 1999 / Accepted: 3 June 1999     

Elemental analysis of airborne dust samples with TXRF: Comparison of oxygen-plasma ashing on sapphire carriers and acid digestion for sample preparation

The concentrations of 13 elements (As, Ca, Co, Cd, Cr, Fe, Ga, Ni, Pb, Pt, Ti, V and Zn) were determined in air particulate matter using total reflection X-ray fluorescence spectrometry (TXRF). For silicon analysis synthetic sapphire was chosen as a new sample carrier material – it is silicon-free, resistant to oxygen-plasma, microwaves and concentrated acids. The dust samples were collected on cellulose acetate filters. The decomposition of the filters was carried out by oxidation in a microwave-generated low-pressure oxygen-plasma directly on the TXRF sample carriers. The recovery of the investigated elements was verified with the standard reference material SRM 1648 (urban particulate matter) and ranged from 90 to 97%. The oxygen-plasma method was compared with conventional sample preparation by acid digestion. Received: 9 April 1999 / Revised: 18 May 1999 / Accepted: 3 June 1999     

Optimization of an urban particulate matter multi-element analysis method by inductively coupled plasma--atomic emission spectrometry (ICP-AES)

In the present work a method for simultaneous metals determination, in urban air particulate matter by ICP-AES has been set up. A large number of elements (18) has been analyzed, including major (Al, Fe, K, and Mg), minor (Na, Pb and Zn) and trace (As, Cd, Co, Cr, Cu, Hg, Mn, Ni, Sb, Sr and V) elements. The procedure consists of microwave sample acidic total digestion by HNO3/HF mixture and subsequent analysis by ICP-AES, using different assemblies depending on sample treatment procedure: a quartz Meinhard nebulizer/cyclonic chamber, if HF excess was eliminated, or a cross-flow nebulizer/plastic Scott chamber, suitable for application with HF. A cyclonic chamber for hydride generation was used for As, Sb and Hg determination. The procedure was tested with Standard Reference Materials 1648 NIST Urban Particulate Matter and Certified Reference Material No8 NIES "Vehicle Exhaust Particulates". Two sampling supports, quartz fibre and polycarbonate filters, have been examined in order to find the most suitable i.e. the one characterized by less interference. Some real samples of urban air particulate matter, TSP, PM10 and PM2.5 fractions, collected during an intercomparison campaign promoted by Regione Lombardia, have been analyzed with the procedure developed.     

Comparison of hexamethylenedithiocarbamate and tetramethylenedithiocarbamate as flotation reagents for the concentration of zinc

A procedure for zinc flotation separation from fresh water prior to its determination by atomic absorption spectrometry (AAS) has been developed. Hexamethyleneammonium hexamethylenedithiocarbamate (HMA-HMDTC) added to the first precipitate collector of hydrated Fe(III) oxide (Fe₂O₃· xH₂O) gives the second precipitate collector of Fe(HMDTC)₃. After addition of a surfactant, the precipitate of collectors is separated from the water phase by a stream of air bubbles, dissolved by strong acid and the solution then tested by AAS. The experimental parameters (amount of collector used, pH, ionic strength, type of foaming reagent, ζ potential, induction time etc.) affecting the flotation efficiency were optimized. At a pH of 6, Zn is separated quantitatively (98.5%) by addition of 5 mg Fe(III) and 3 mL 0.1 mol/L HMA-HMDTC to the sample. Results are compared with those obtained by ammonium tetramethylenedithiocarbamate. Received: 21 August 1997 /Revised: 19 November 1997 / Accepted: 23 November 1997     

Association of uranium with colloidal and suspended particulate matter in Arabian sea near the west coast of Maharashtra (India)

The purpose of the present study is the association of natural uranium in seawater with colloidal and suspended-particulate matter was determined. The separation of suspended particulate material (>0.45 µm) and colloidal fraction (as dissolved fractions) in seawater were done by suction and ultra filtration techniques. Seawater samples were collected at 1 km away from the shore and subjected to sequential fractionation in nine stages ranging from 2.7 µm to 1.1 nm. Suspended particulate matter were separated in three different size groups namely >2.7 µm, <2.7–>0.45 µm and <0.45–>0.22 µm by suction filtration using cellulose acetate and nitrate membranes filters. To concentrate the solution with colloidal particles <0.22 µm–1.1 nm (0.5 k Nominal Molecular Weight cut-off Limit {NMWL}), the solution obtained from filtration through <0.22 µm was passed through stirred ultra-filtration cell. The pH and conductivity at different stages of fractionation (dissolved) showed minor variations. The concentration of uranium was measured in suspended and dissolved fractions by using a pulsed nitrogen laser at 337.1 nm. In order to evaluate the role of mineral colloids in various stages of filtration, concentration of calcium, magnesium, potassium were measured by using ion chromatography and atomic absorption spectrometry. The clay mineral at seawater pH (approximately 8) behave as negative ions and provides binding site for the positively charge species of uranium. Among the dissolved fraction, the maximum concentrations of colloidal uranium was observed about 4 times higher than that compared to average concentration of 6.93±3.10 ppb in other fractions. In the case of suspended particulate matter, the concentration of uranium was below detection limits (<1 ppb). The maximum concentration of Ca, Mg and K in the dissolved fraction were in the <1.1 nm fraction, while for suspended particulate matter, the concentration of Ca, Mg and K decreased with the decrease in size and it is highest in the fraction of 0.22 –0.45 µm.This revised version was published online in November 2005 with corrections to the Cover Date.     

Plutonium-239+240 selectivity for pseudo-colloids of iron in subsurface aquatic environment having elevated level of dissolved organic carbon

Laboratory simulated experiments have been conducted to study the association of ^239,240Pu with pseudo-colloids of iron in groundwater samples having dissolved organic carbon (DOC) in the range of 10–60 mg L⁻¹. Ultra-filtration membranes have been used to partition colloidal components into seven different size range of <0.45 μm-1.1 nm. Elevated levels of Fe, DOC and ^239,240Pu were observed in the fractions concentrated with 1.6 nm (10,000 NMWL) and 1.1 nm (500 NMWL) compared to the other dissolved fractions. To ascertain the fact that, the formation of pseudo-colloids of Fe in the size range 1.6 nm and 1.1 nm was assisted by the presence of DOC, experiments have been conducted under similar experimental conditions with uniform Fe concentration and varying the DOC in the range of 10–60 mg L⁻¹. Seven to eight times higher concentration of Fe was observed in fractions concentrated with 1.6 nm and 1.1 nm having DOC ≥30 mg L⁻¹, whereas Fe was equally distributed in all the fractions in groundwater having DOC ≥10 mg L⁻¹. The surface morphology and composition of the residue left on the ultra-filtration membranes was examined using scanning electron microscope (SEM) coupled with energy dispersive X-ray spectrometer (EDS). The EDS results validate the observation that the residue left on filter paper membrane of 10000 and 500 NMWL with pore size 1.6 and 1.1 nm respectively, shows elevated levels of carbon and Fe contents as compared to other fractions. Understanding the association of ^239,240Pu with Fe and DOC will facilitate in predicating the long term integrity of underground waste storage facilities of alpha emitting radioactive material.     

A flow system for calibration of dissolved oxygen sensors

Well-defined oxygen standard solutions were obtained by the electrolysis of water in a coulometric oxygen generator. The generator was integrated into a flow system that includes the degassing of the carrier electrolyte, the generation of dissolved oxygen and the temperature control of the carrier electrolyte. The current efficiency of oxygen generation was found to be 100% by the Winkler titration method. Calibrations of a home made laboratory sensor and a WTW CellOx dissolved oxygen sensor have been made in a concentration range of 0.02 to 8 mg/L at temperatures from 5°C to 30°C. The calibration of the WTW sensor on water vapour saturated air was compared with the electrochemical calibration method. Both methods gave reliable results provided that the temperature equilibration between the sensor and the ambient air was successful. Received: 24 March 1997 / Revised: 15 May 1997 / Accepted: 15 May 1997     

Sources of 137Cs fluvial export from a forest catchment evaluated by stable carbon and nitrogen isotopic characterization of organic matter

Fluvial export of particulate and dissolved ¹³⁷Cs was investigated to reveal its sources and transfer mechanisms in a broadleaved forest catchment using a continuous collection system. The finest size fraction (<75 µm), consisting of decomposed litter and surface mineral soil, was the dominant fraction in the particulate ¹³⁷Cs load, although the contribution of coarser size fractions increased during high water discharge in 2014. The dissolved ¹³⁷Cs originated from the decomposition of ¹³⁷Cs-contaminated litter. Temporal changes in ¹³⁷Cs distribution in the litter–mineral soil system indicated that the dissolved ¹³⁷Cs load will be moderated in several years, while particulate ¹³⁷Cs load has the potential to continue for a long time.