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EN
This article aims to investigate in detail to what extent surfactants affect the determination of cadmium by anodic stripping voltammetry. In recent years, the production and use of surfactants have been steadily increasing, so that their concentration in environmental water samples is rising. At the same time, it is known that organic compounds, such as surfactants, often hinder the voltammetric determination of trace elements by stripping. Non-ionic (Triton X-100, Brij 35, Tween 20, Tween 60, Tween 80), cationic (CTAB, CTAC, DTAB, HPC) and anionic (DSS, SDS) compounds were selected to investigate the effect of surfactants on the voltammetric signal of cadmium. At the same time, the extent to which the addition of Amberlite resins to the analysed solution eliminates the interfering effect of surfactants was tested. Three types of Amberlite resins XAD-2, XAD-7 and XAD-16 were selected for the study and the ratio of resin weight to solution volume was determined. Finally, the determination of cadmium in surfactant-enriched environmental samples was carried out. The recoveries obtained between 95.5 and 107%, with RSD between 3.4 and 6.2%, confirm the validity and correctness of the proposed procedure All measurements were carried out by anodic stripping voltammetry using a CNTs/SGC electrode modified with a bismuth film as the working electrode.
EN
Variations in structure and color of the shell of freshwater Ostracoda crustacean genus Cypris were used as a biomarker to detect the impact of heavy metals, i.e. cadmium in the form of CdCl2 as a case of study. Concentrations of element used in experimental were submitted with their levels that were detected in Iraqi aquatic environment and the expected ranges resulting from the accumulation of these metals in aquatic systems. Therefore, salts of CdCl2 were used to prepare the required concentrations 0.1, 0.1.5, 0.2, and 0.3 mg/L, respectively. Individuals of crustacean were taken at the rate of 10 adults (A) and 10 juveniles (J) at three replicates and the exposure time was recorded, at 6, 12, 24, 48 hours, and the tests were conducted under controlled laboratory conditions of light, pH, and temperature. The results showed that all individuals, A and J, were affected after 12 hours of treatment with CdCl2, and observed slight differences in the level of impact, the activity and resistance of Cypris individuals to the impact of element that began with exchanged of color and density of shell, level of the flexibility of shell legator flap muscle within 24 hours, followed by opening and cracking all the shell over 48 hours and exposed the internal structures of the crustacean to direct impact of Cd. When following up on the survival and mortality rate at the level of individuals and comparing the speed of vulnerability of adults and juveniles, differences between both categories of individuals can be noticed, as death rates were recorded after 12 and 24 hours of treatment, amounting to 60 and 70%, respectively, at a concentration of 0.1 mg/L, while with concentrations 0.1.5 and 0.2 mg /L, the percentage increased in J to 80%, but at concentration 0.3, the percentage of mortality rate was equal and became 90% after 24 hours in A and J. The death rate of 100% was recorded with all concentrations used in the experiments after passage 48 hours of treatment with cadmium.
EN
Among a number of climate-related factors, moisture has the greatest impact on crop productivity. In recent years, certain changes have been observed under conditions of the Forest-Steppe of Ukraine with regard to precipitation – from low to in some cases – abnormally high, which requires the study of their impact on the yield and safety of cereal grain for its forecasted production. The article examined the effect of a high level of soil moisture (256.2–272.5 mm) and a low level (47.4–52.3 mm) during the growing season (germination→earing) of spring barley grain on the accumulation of heavy metals in it and its productivity under the conditions of gray forest soils of the Right Bank Forest Steppe of Ukraine. Spring barley varieties Helios and Caesar were selected for the research. A decrease in the accumulation coefficient at a high level of soil moisture (256.6–272.5 mm) in spring barley grain Pb from 8.3% to 11.3%, Cd – from 35.0% to 35.5%, Zn was established – by 15% and Cu – from 11.2% to 16.6% compared to the low level of soil moisture (47.1 mm – 53.3 mm). At the same time, it was found that with a high level of soil moisture, there is a decrease in the yield of Helios and Caesar spring barley by 18.0% and 14.1%, respectively.
EN
Using water hyacinth as a phytoremediation agent produces abundant biomass due to periodic harvesting in the system. One of the alternative uses of water hyacinth biomass can be a bio-sorbent to absorb metal contamination in the waters. This study aims to determine the quality of activated water hyacinth bio-sorbent, potentially reducing metal cadmium (Cd). The research was conducted from January to April 2022. The results showed that the parameters of water content, iodine absorption, and methylene blue in water hyacinth bio-sorbent had met the quality standard of activated carbon based on SNI No. 06-3730-1995. In contrast, the ash content still did not. In water, hyacinth stem bio-sorbents (stems + ZnCl2 and stems 300 °C + ZnCl2) obtained higher ash content (25.87 and 73.30%) than the ash content of water hyacinth root and leaf bio-sorbent with the same activation treatment. The optimum adsorption capacity (Qe) for the roots + ZnCl2 occurred at a contact time of 45 minutes which was 8.13 mg/g with an absorption efficiency (Ef) of 34.20%. For the root 300 °C + ZnCl2, the optimum adsorption capacity and absorption efficiency occurred at a contact time of 8 hours, namely 9.08 mg/g and 38.66%, respectively. The optimum adsorption capacity and absorption efficiency of the leaves + ZnCl2 occurred at a contact time of 4 hours, namely 7.63 mg/g and 32.12%, respectively. Meanwhile, at the leaves 300 °C + ZnCl2, the optimum adsorption capacity and absorption efficiency occurred at a contact time of 8 hours with a value of Qe = 11.84 mg/g and Ef = 49.35%.
EN
This study goal to the ability of using low cost materials representing thermestone and aluminum solid wastes in water filtration by using a pilot plant constructed in wastewater treatment plant to remove cadmium ions (Cd(II)). Response Surface Methodology (RSM) used to optimize the optimal parameters that affecting the performance of filter units, these parameters are time, Cd(II) concentration, and filtration rate. These optimized parameters were 9 hr., 5 ppm, 10 l/hr. with removal efficiency of Cd(II) for A-Filter, T-Filter, S-Filter, and A-T-S-Filter was 94%, 95%, 86.8% and 90%, respectively. The result shows that the T-filter has higher cadmium removal efficiency than A-filter, S-filter and S-T-A- filter. While A-filter has a higher removal efficiency of cadmium than the S-filter and S-T-A- filter. While the S-T-A- filter has higher efficiency than S- filter. The result obtained from RSM was good Agreement with the result of experiments. As a result, the optimized process in this paper can be widely utilized with high removal ratio of Cd(II) ions from wastewater samples.
EN
For this study, an electro kinetic method used to eliminate cadmium from the polluted soil. This method is useful at low permeability medium. Several experiments were conducted with variable operating circumstances, using different pH purging solutions. Rice husks were used in this work as an adsorbent medium available and free of charge to counteract the reverse osmosis process that occurs and affects the work efficiency. The final results after the end of the practical experiments of this process showed that the percentages of the removal process began to increase after the pH gradually decreases. The pH of the solution for the three experiments conducted was 3, 6 and 9, respectively. The best removal rate was 68% in this process at pH 3 ; when compared with the second and third tests at pH 6 and 9, the removal ratios were 58% and 51.5%, respectively. It was discovered that the cadmium removal rate began to decrease along with voltage. At 30 volts the removal rates were 68%, whereas 20 volts they were 66%. Rice husks have been shown to be an effective adsorbent for counteracting reverse osmosis. Therefore, it can be successfully used as an adsorbent medium.
PL
Kadm i jego związki nieorganiczne powodują raka płuc. Wykazano także zależność między narażeniem ludzi na kadm i jego związki a rakiem nerek i prostaty. Szacuje się, że na kadm i jego związki jest narażonych kilka tysięcy osób zatrudnionych w hutnictwie, przy produkcji akumulatorów, stopów, pigmentów, tworzyw sztucznych oraz przy spawaniu. W Polsce wartość najwyższego dopuszczalnego stężenia (NDS) dla kadmu (CAS: 7440-43-9) i jego związków nieorganicznych została zmieniona. Wartość NDS mająca obowiązywać od 2027 roku odnosi się do frakcji wdychalnej i wynosi 0,001 mg/m³ . W okresie przejściowym od lipca 2021 do 2027 roku przyjęto wartość NDS wynoszącą 0,004 mg/m³ . Opracowano metodę oznaczania kadmu i jego nieorganicznych związków umożliwiającą oznaczanie tej substancji w powietrzu na stanowiskach pracy z wykorzystaniem metody absorpcyjnej spektrometrii atomowej z elektrotermiczną atomizacją (ET-AAS), zgodną z wymaganiami zawartymi w normie europejskiej PN-EN 482. Kadm oznaczano w zakresie stężeń: 0,10 ÷ 1,00 i 0,50 ÷ 5,00 µg/l. Uzyskano oznaczalność metody w powietrzu na stanowiskach pracy wynoszącą 0,0001 mg/m³ oraz możliwość oznaczania tej substancji w zakresie stężeń 0,00010 ÷ 0,0104 mg/m³ dla próbki powietrza 480 l. Przedstawiona metoda umożliwia oznaczanie kadmu i jego związków nieorganicznych w powietrzu na stanowiskach pracy w wymaganym zakresie 0,1 ÷ 2 nowych wartości NDS. Zakres tematyczny artykułu obejmuje zagadnienia zdrowia oraz bezpieczeństwa i higieny środowiska pracy będące przedmiotem badań z zakresu nauk o zdrowiu oraz inżynierii środowiska.
EN
Cadmium and its inorganic compounds cause lung cancer. A relationship between human exposure to cadmium and its inorganic compounds and renal and prostate cancer has also been demonstrated. It is estimated that several thousand people employed in metal production are exposed to cadmium and its inorganic compounds; in metallurgy, in the production batteries, alloys, pigments, plastics and welders. The values of the maximum allowable concentration (NDS) for cadmium [7440-43-9] and its inorganic compounds in Poland were changed. The NDS value, which is meant to become obligatory from 2027, refers to the inhalable fraction and amounts to 0.001 mg/m³ . In the transition period from July 2021 to 2027, the NDS value was set at 0.004 mg/m³ . A method for the determination of cadmium and its inorganic compounds was developed, enabling the determination of this substance in the air at workplaces with the use of the atomic absorption spectrometry with electrothermal atomization (ET AAS), in accordance with the requirements of the European standard PN-EN 482. Cadmium was determined in the concentration range: 0.10–1.00 µg/l and 0.50–5.00 µg/l. The method’s determination in the air at workplaces of 0.0001 mg/m³ was obtained for, as well as the possibility of determining this substance in the concentration range of 0.00010–0.0104 mg/m³ for a 480-l air sample. The presented method enables the determination of this substance in the air at workplaces in the required range of 0.1–2 new NDS values. This article discusses the problems of occupational safety and health, which are covered by health sciences and environmental engineering.
EN
Polymer enhanced ultrafiltration (PEUF) technique economically enables separation and/or retention of various heavy metal ions from aqueous solutions for environmental and engineering problems. Polyethylenimine as the water-soluble complexation agent utilized to interact with heavy metal ions of Cd and Ni as cations in ultrafiltration experiments were modeled with protonation data to understand the mechanism. Test runs showed that an enrichment coefficient (the ratio of Cd over Ni in permeate) up to 10 was obtained at pH 4.2 in the temperature range of 20-22oC, whereas full retention of both cations is possible above pH 5.0 and those results are highly compatible with the model developed.
EN
The aim of this research was to study the effects of chemical (CH) and bioproduct (MIC) fertilizers on rice growth (plant height), rice yield (full grains), and the decrease in cadmium (Cd) contents in soil and rice grains. A silty clay loam (SCL) soil for growing rice was prepared in the laboratory, with Cd addition and pH control. The relationship between CH and MIC fertilizer additions in various amounts with the reduction in the Cd contents of soil and rice grains was explored. As a result, the rice growth in the harvest phase and the yield increased from 138.80 ± 5.72 to 888.40 ± 2.38 cm⋅plant-1 and 689 to 888 seeds⋅plant-1, respectively, when the bioproduct was increased from MIC100 (0.625 L⋅ha-1) to MIC500 (3.125 L⋅ha-1). The Cd content in the soil during the harvest phase, 35.53 mg⋅kg-1, which was less than the standard value of 37.00 mg⋅kg-1 defined by the Pollution Control Department (PCD), Thailand, decreased when the bioproduct increased to MIC500. For the Cd contents in polished rice grains, when MIC500 was added, 0.19 mg⋅kg-1 of Cd was accumulated, which is acceptable according to the Codex Committee on Food Additives and Contaminants (CCFAC) threshold of 0.20 mg⋅kg-1 for Cd. Thus, MIC500 was the most effective in reducing the Cd accumulation in soil and rice grains and promoting rice growth among all MIC amounts.
EN
Cadmium (Cd) is toxic for humans, but its effects on the yield and quality of rice under contaminated irrigation conditions remain uncertain. In this study, paddy soils in the Red River Delta (Vietnam) were selected for experiments with the purpose of understanding the effects of Cd contaminated irrigation water on growth, yields, and grain Cd accumulation. In addition, biochar was produced from rice husk (BRH) and rice straw for preventing Cd infiltration into rice was also studied in this experiment. A field experiment was established with applicated BRH and straw into polluted paddy soil, as a result the Cd content in grains reduced significantly. The Cd contaminated soil was added to the BRH and rice straw (RS) with six ratios, including: (1) RS 2.5%, (2) BRH 2.5%, (3) RS-BRH: 1.25–1.25%, (4) RS 5.0%, (5) BRH 5.0%, (6) RS-BRH: 2.5–2.5%, (w:w). Besides, three content levels 0.01–0.05–0.5 mg/L of Cd in irrigation water were applied throughout crop season. The results showed that the Cd accumulation in rice was in the following order: roots > stems > seeds. With 3 contaminated irrigation levels which were applied, the Cd concentrations of 0.05 mg/L and 0.5 mg/L affected plant height and yield. However, the Cd content in grains under contaminated soil condition can be controlled from 82.47–83.94% by applying a BRH ratio from 2.5–5% (w:w).
EN
It was found that date seeds are suitable for biochar production due to their low moisture content 8.92%, low ash yield 1.05%, and high organic matter content 78.3%. The biochar was produced by pyrolysis at 350, 450 and 550°C. The effect of pyrolysis temperature on the physicochemical characteristics of biochar was investigated. It was found that the porosity, water holding capacity, ash content, pH, organic matter, fixed carbon, and the elemental content of Na, K, Ca, Mg, Fe, Mn, P, Zn, Ba, Cr, Cu, Ni, Pb, Ti, and V were increased along with pyrolysis temperature. Meanwhile, the biochar yield, bulk density, and the total content of N and S were decreased. The biochar was tested as a sustainable adsorbent to investigate the adsorption of Cd from contaminated water. The adsorption isotherms of Cd on biochar were determined based on Langmuir equation. The maximum adsorption of Cd at 25°C and pH 7 were 667, 714, and 833 mg/kg for the biochars produced at 350, 450, and 550°C, respectively. On the basis of the physicochemical characteristics of the biochar and the findings from Langmuir equation that showed the biochar produced at 550°C has the highest adsorption capacity for Cd, the desorption/adsorption experiment was carried out using the biochar produced at 550°C. The adsorption of Cd by biochar was directly proportional to the Cd concentrations. It was increased from 0.009 mmol/0.5g at 0.01 mmol Cd to 0.12 mmol/0.5g at 0.2 mmol Cd concentration. The desorption of Cd from biochar was increased proportionally to cadmium concentrations from 0.01 to 0.05 mmol and became constant above 0.05 mmol, regardless of the increment of cadmium concentrations. High retention potential for the cadmium that adsorbed within the biochar was proven in this study with desorption/adsorption percentage of 16%. These findings provide a successful example of date seeds converting into the sustainable adsorbent for Cd removal from aquatic environment to achieve the conception of eco-friendly production, which should be studied further.
EN
The chemical composition of surface waters of the Przemsza River flowing through Upper Silesia (in southern Poland) is strongly affected by Zn and Pb ore, and less by Carboniferous hard coal deposits. The chemical type of surface water is Ca-HCO3. In the waters, three groups of metals and metalloids were found that directly interfere with the mineralization of the deposit. Although genetically related to the same deposit, each group exhibits a different fate in the environment. A typical deposit association is Pb-Zn-Ag-As-Sb-Hg. The first group of metals in surface waters is consistent with the typical association of the ore Zn-Pb-Cd-(Tl), the second includes Ag-Sb-Hg, and the third includes the additives in the zinc and lead ore Co-Ni-Mo-Mn: [formula]. Depending on the pH-Eh conditions, metals and metalloids precipitate out of the solution or sorb on solid particles. The concentrations of individual groups of metals are interdependent but show different environmental fates along the river course. The natural process of the enrichment of surface waters with Zn-Pb-Cd-(Tl) is by water circulation in a rock matrix naturally rich in the metals and draining groundwaters by the river. Under oxidizing and slightly alkaline conditions, Ag-Sb-Hg incorporated into the soluted chemical compounds, may, when the physicochemical parameters of the waters change, be adsorbed and/or precipitated. The presence and ratio of concentrations of Co-Ni-Mo-Mn with respect to zinc are almost identical, differing only in concentration.
EN
Water contamination that caused by heavy metals is a very common phenomenon in the industrial age. One of the popular way to treat metal contaminated water is by adsorption process using activated carbon as the adsorbent. This paper works on producing activated carbon by chemical means with impregnation ratios of NaOH:char (w/w) was predetermined at 1:1 (ACT1-1), 2:1 (ACT2-1) and 3:1 (ACT3-1) under activation temperature of 700°C. Considering the Leucaena leucocephala is a wildly, easy and fast grown species, with the availability throught the year, it was chosen to be used as the precursor. The properties of these activated carbons and its potential for cadmium removal from aqueus solution was analyzed. It was found that the highest surface area was recorded at 662.76 m²/g. Four parameters were studied which are contact time, the effect of pH, initial concentration of adsorbate and temperature. The equilibrium time was achieved in 40 min treatment at initial concentrations of 30 mg/l. The adsorbent exhibited good sorption potential for cadmium at pH 8.0 and equilibrium temperature of 30℃. Based on the results, this study had proved that activated carbon from Leucaena leucocephala biomass have the good potential to be used for removal of cadmium from wastewater.
EN
The study presents the possibility of using chlorophyta in the removal of cadmium and lead ions from industrial wastewater produced after the washing of equipment used in the manufacture of battery and batteries. The process was conducted with the use of two algal cultures: Raphidocelis subcapitata produced in laboratory conditions, and a mixed chlorophyta population collected from a natural, eutrophicated water reservoir with heavy metal ions present in the water and sludge. The study showed that the effectiveness of a pure algal culture is comparable to that of a mixed chlorophyta population, characterized by greater diversity of functional groups at binding sites and higher resistance to stress that may occur in the wastewater environment. The maximum effectiveness of ions sorption was 64% for cadmium (mixed algal population) and 60% for lead (Raphidocelis subcapitata).
EN
The heavy metal pollution in seawater and sediment can damage mangrove ecosystems and accumulate in mudskipper (Periophthalmus spp.) that lives in mangrove forests. The accumulation of heavy metal in mudskipper can affect the structure of its gill tissue, liver, and muscles. This research aims at (1) analyzing the levels of lead, cadmium and cuprum heavy metals in mudskipper, sediment, and seawater and (2) analyzing the damage to the gill, liver, and muscle tissue of mudskipper due to the exposure to heavy metals. The mudskipper samples were collected from the mangrove forests of Poka, Waai, and Rutong from May to June in 2019. The heavy metal analysis was conducted using the AAS method, while the gill, liver and muscle tissue staining was carried out with the HE (Hematoxylin Eosin) staining method with 40x magnification. The data were analyzed using descriptive analysis and correlational analysis. The results of the analysis showed that based on the mangrove locations, the order of Pb and Cu accumulation in mudskipper was Rutong> Poka> Waai; while the order of the Cd accumulation was Rutong> Waai> Poka. The changes in the gill tissue structure due to the exposure to heavy metals were in the form of teleangiectasia, secondary lamellar edema, hyperplasia, epithelial desquamation, clubbing, and primary lamellar edema. The changes in the liver tissue structure due to the exposure to heavy metals involved hemorrhage and fat degeneration. The changes in the muscle tissue structure due to the exposure to heavy metals include changes in muscle fibers, edema, and necrosis. The highest accumulation of Pb and Cd was found in gills and muscles from seawater, while low level of heavy metal Cu was found in the liver.
EN
A hydroponic trial was conducted to study the effect of chloride salinity in simulated effluent on Cd accumulation by tobacco. Leaf surface area (LSA) and root surface area (RSA) measurements were incorporated as possible determinants of Cd uptake rate by plants. Results showed that individual plant differences in Cd content were normalized when including RSA to express Cd uptake rates by plants but not including LSA. A biotic ligand model (BLM) fitted to predict Cd uptake, estimated active and almost linear uptake of the free Cd2+ ion by tobacco plants, while virtually no changes in the chloride complex (CdCl+) uptake were predicted, presumably due to a rapid saturation of the hypothetical root sorption sites at the concentrations used in this trial. Nicotiana tabacum var. K326 is evidenced to be a species potentially suitable for biological wastewater treatment using rhizofiltration at concentrations commonly found in salt-affected wastewater, with high Cd accumulation (185 to 280 mg/kgdm) regardless of water salinity and tolerance up to 80 mmol/L NaCl.
PL
Żywność oprócz składników odżywczych może zawierać także substancje, które stanowią zagrożenie dla zdrowia. Przykładem takiego zagrożenia jest obecność w produktach spożywczych metali ciężkich. Zanieczyszczenia te należy zaliczyć do skażeń chemicznych powstałych w wyniku różnych procesów naturalnych, przetwórczych, migracji oraz przypadkowych skażeń. Metale ciężkie uznaje się obecnie za jedne z najgroźniejszych zanieczyszczeń środowiska człowieka. Do najbardziej toksycznych należy kadm, ołów, rtęć oraz arsen. Pierwiastki te odznaczają się najwyższym współczynnikiem kumulacji. W artykule przedstawiono dane literaturowe na temat zawartości metali ciężkich w niektórych podstawowych produktach spożywczych (warzywach i owocach, artykułach pochodzenia zwierzęcego: mleku, mięsie oraz rybach). Dodatkowo na podstawie raportów RASFF dokonano analizy występowania zagrożeń chemicznych w żywności z uwzględnieniem tendencji oraz częstotliwości ich zgłaszania w analizowanym okresie.
EN
In addition to nutrients, food also contains substances that can pose health risk. Heavy metals are one such threat. These impurities should be classified as chemical contamination resulting from various natural, processing and migration processes as well as accidental contamination. Heavy metals are currently one of the most dangerous environmental pollutants. The most toxic include cadmium, lead, mercury and arsenic. These elements have the highest accumulation coefficient. The article presents results of heavy metal content in some basic food products (vegetables and fruits, products of animal origin - milk, meat, fish). Additionally, based on RASFF reports, an analysis of the occurrence of chemical hazards in food was made taking into account trends and the frequency of reporting them in the analyzed period.
EN
Heavy metals like cadmium (Cd) and lead (Pb) are pollutants that are toxic, difficult to decompose and accumulate in biota. One of the biota that lives in the waters is mullet fish. This fish is demersal, has a relatively long life period, has a specific tolerance to the aquatic environment and highly consumable in Indonesia. Therefore need to know the metal content of Cd and Pb in water, sediments and mullet fish and their relationship in Indonesia. The study used a survey method with purposive random sampling at four stations, three replications. The study was conducted from June to November 2019. Analysis of data was descriptive, F-test and correlation. The results showed that the heavy metal content of Cd and Pb between stations in the water media, sediment and in mullet fish there was a significant difference. The highest Cd and Pb were showed in station III, coming from the oil industry, domestic waste and transportation activities. The heavy metal content of Cd and Pb in water, sediment and mullet fish (Planiliza subviridis) in the Donan River, Cilacap shows results exceeding the allowed threshold and danger to human health.
EN
This paper examines the process and methodological aspects of implementing online X-ray fluorescence monitoring of ore in terms of its silver, cadmium, zinc, lead, molybdenum, and iron grade at the process conveyors at Balkhash and Karagaily Concentrators and the main conveyor of the Nurkazgan underground mine operated by Kazakhmys Corporation LLC. The research was complicated by the need to: a) ensure reliable measurement of silver and cadmium in the range of 1+ ppm, molybdenum in the range of 10+ ppm, as well as copper, zinc, lead, and iron in the ore size class –300 mm; b) implement monitoring of the grade of these elements (except molybdenum) at Balkhash Concentrator in the waste slag of Balkhash Copper Smelter, characterized by a very complex elemental matrix. A modification of the ore monitoring station RLP-21T (by Aspap Geo LLC, Alma-Ata) was developed, implemented, and thoroughly tested for online monitoring of low-grade silver ore flows. Energy dispersive X-ray fluorescence method was adopted for ore assays. Instrument spectra were measured every second. Silver, cadmium, and molybdenum grade was calculated based on 40 measurements, copper, zinc, lead, and iron grade – based on 20 measurements.
PL
W artykule przeanalizowano proces i aspekty metodologiczne wdrażania zdalnego monitorowania zawartości srebra, kadmu, cynku, ołowiu, molibdenu i żelaza w zakładach wzbogacania Balkhash i Karagaily oraz na głównym przenośniku w kopalni podziemnej Nurkazgan obsługiwana przez Kazakhmys Corporation LLC. Badania były skomplikowane ze względu na konieczność: a) zapewnienia niezawodnego pomiaru srebra i kadmu w zakresie 1+ ppm, molibdenu w zakresie 10+ ppm, a także miedzi, cynku, ołowiu i żelaza w klasie –300 mm; b) wdrożyć monitorowanie tych pierwiastków (z wyjątkiem molibdenu) w koncentracie Balkhash ,w żużlu odpadowym Huty Miedzi Balkhash, charakteryzującym się bardzo złożoną matrycą elementarną. Opracowano, wdrożono i dokładnie przetestowano modyfikację stacji monitorowania rudy RLP-21T (firmy Aspap Geo LLC, Alma-Ata) do monitorowania online przepływów rudy srebra o niskiej jakości. Do fluorescencji rentgenowskiej zastosowano dyspersyjną metodę rentgenowską. Widma mierzono co sekundę. Zawartość srebra, kadmu i molibdenu obliczono na podstawie 40 pomiarów, a miedzi, cynku, ołowiu i żelaza – na podstawie 20 pomiarów.
EN
Polychlorinated substances, polyaromatic hydrocarbons, heavy metals and pesticides are among the priority even at low concentrations. The problem, however, is that such low concentrations are impossible to measure using most available methods. This research focused on the determination of selected priority substances – heavy metals, namely lead and cadmium, in which the determination of Pb and Cd in wastewater by Inductively Coupled Plasma Mass Spectrometry (ICP-MS) was preceded by water sample pre-treatment. The paper deals with the influence of the pre-treatment on the resulting measured values. Two processes were selected as pre-treatment processes. The first pre-treatment procedure was a simple filtration using a filter paper for moderate filtration. As the second procedure, we applied decomposition of the sample by nitric acid in the open system. The pre-treated wastewater samples were subsequently examined using ICP-MS. Based on the obtained results, we can conclude that decomposition of the sample by nitric acid in the open system is a more suitable pre-treatment method for water samples.
PL
Zawartość substancje polichlorowanych, węglowodorów poliaromatycznych, metali ciężkich i pestycydów ma ogromne znaczenie nawet przy niskich stężeniach. Problem polega na tym, że niskich stężeń nie można zmierzyć przy użyciu większości dostępnych metod. Badania koncentrowały się na oznaczeniu wybranych substancji priorytetowych – metali ciężkich, a mianowicie ołowiu i kadmu, w których oznaczanie Pb i Cd w ściekach metodą indukcyjnie sprzężonej plazmowej spektrometrii masowej (ICP-MS) poprzedziło wstępne uzdatnianie próbki wody. Artykuł dotyczy wpływu obróbki wstępnej na uzyskane wartości pomiarowe. Dwa procesy wybrano jako procesy obróbki wstępnej. Pierwszą procedurą wstępnej obróbki była prosta filtracja z użyciem bibuły filtracyjnej do umiarkowanej filtracji. W drugiej procedurze zastosowano rozkład próbki kwasem azotowym w układzie otwartym. Wstępnie oczyszczone próbki ścieków zostały następnie zbadane przy użyciu ICP-MS. Na podstawie uzyskanych wyników stwierdzono, że rozkład próbki kwasem azotowym w układzie otwartym jest bardziej odpowiednią metodą wstępnej obróbki próbek wody.
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