Long-term mobility of uranium in the granitic KURT site using isotopic analysis and sequential chemical extraction

2020 ◽  
Vol 326 (2) ◽  
pp. 1173-1183
Author(s):  
Min Hoon Baik ◽  
Jae Kwang Lee
2007 ◽  
pp. 429-438
Author(s):  
Dominica del Mundo Dacera ◽  
Sandhya Babel

Heavy metals in sewage sludge can pose a long term environmental risk due to their toxicity,non-biodegradability and consequent persistence, This study assessed the efficiencies ofvarious organic extractants such as naturally fermented and A�pergillus niger (A. niger)fermented raw liquid from pineapple wastes, in the chemical extraction process, to extract Cr,Cu, Pb, Ni and Zn, from anaerobically digested sewage sludge in Thailand. Pineapple wastesare a good source of sugar and protein and have been utilized experimentally in theproduction of citric acid by fennentation with the fungus A. niger. Comparison of theextraction efficiencies of these extractants with commercial citric acid was also investigated attwo hours leaching time and pH 3 and greater. Results of the study revealed that at pHapproaching 4, A. niger fermented liquid seemed to exhibit the best removal efficiency forpractically all metals studied, attaining as much as 72% removal for Zn, 70% for Ni, 50% forCr and 37% for Cu, although effectivity of removal seemed to be less apparent for Pb. Themost readily solubilized metal seemed to be Zn with the most removal of 92% attained bynaturally fermented raw liquid, The effectivity of removal by A. niger fem1ented liquid maybe due to the presence of citric acid and other carboxylic acids as confirmed by the HPLC andIR studies of the fem1ented liquid, Moreover, variation in metal removal efficiencies may beattributed to the fonns of metals in the sludge, as evidenced by chemical speciation studiesusing sequential chemical extraction procedure, with metals predominantly in theexchangeable and oxidizable phases showing ease of leachability,


2011 ◽  
Vol 2011 ◽  
pp. 1-20 ◽  
Author(s):  
R. Burt ◽  
T. Weber ◽  
S. Park ◽  
S. Yochum ◽  
R. Ferguson

Long-term mining activities in the mountains around Creede, Colorado have resulted in significant contamination in soils and water in the Willow Creek floodplain. Total major and trace were determined for soils and water and sequential chemical extraction for soils. Objectives were to determine concentrations and potential reactivity of trace elements and investigate their relationship with other soil and water properties. Water trace elements showed significant variability among sites, ranging from 347 to 12108 μg/L. Relative trend showed (Zn > Sr > Ba) > (Mn > W > Cd) > (Sn > V≈Ni≈Cu > Co) > (Ag). Soil trace elements showed significant short-range spatial variability, ranging from 2819 to 19274 mg/kg. Relative trend showed (Pb≈Zn > Mn > Ba > P) > (As > Cu > Sr > V > Cd > Sb≈Ag) > (Co≈Cr > Mo≈Sn≈Ni) > (Be≈W > Se≈Hg). Predominant fractions were oxide, specifically-sorbed/carbonate bound, and residual. Water soluble and exchangeable fractions showed (Zn≈Cd) > Pb and Cd > Zn > Pb, respectively. Mobility factors for highly contaminated soils showed Cd≈Zn > Pb > Cu > As.


Author(s):  
Khaled D. Alotaibi ◽  
Melissa Arcand ◽  
Noura Ziadi

Abstract Background Continuous application of phosphorus (P) nutrient in association with its low recovery results in large amounts of P being accumulated in soil in different forms. Use of biochar can be a possible means to mobilize soil legacy P and increase its bioavailability. Therefore, the aim of this study was to identify the potential impact of a range of biochar types on P fractions in a long-term cultivated arid soil with high legacy P content. Methodology The soil was treated with biochar produced from four feedstock sources (BFS): sewage sludge (SSB), olive mill pomace (OPB), chicken manure (CMB), and date palm residues (DRB) pyrolyzed at 300, 500, or 700 °C in addition to an untreated control. The soil biochar mixture was incubated for 1 month followed by soil P fractionations using sequential chemical extraction to separate soil P into: labile (Resin-Pi, NaHCO3-Pi, NaHCO3-Po), moderately labile (NaOH-Pi, NaOH-Po), and non-labile (HCl-Pi and Residual-P) pools. Results Biochar addition clearly influenced most of the soil P fractions; however, the extent of this effect greatly varied depending on BFS and pyrolysis temperature (PT). The most evident biochar impact was observed with labile P pool, with the greatest increase being observed in NaHCO3-Pi fraction in most biochar treatments. Irrespective of PT, SSB and CMB were the most effective biochar type in increasing labile inorganic P; the SSB and CMB increased Resin-Pi by 77 and 206% and NaHCO3-Pi by 200 and 188%, respectively. In contrast, DRB made no changes in any P fraction. Differences in effects of biochar types on labile P is presumably related to the higher content of P in biowaste-based biochar compared to plant-based biochar which have much lower P content. The SSB, CMB, and OPB produced at low temperature reduced HCl-Pi content, indicating that these biochars may have stimulated organic matter decomposition and thereby dissolution of non-labile Ca-associated P to labile P forms. Conclusion Overall, biochar addition appeared to be an effective approach in enhancing legacy P availability in arid soil. However, further studies are necessary to verify these findings in the presence of plant and for a longer period. Graphic abstract


Energies ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2361
Author(s):  
Yinjiao Su ◽  
Xuan Liu ◽  
Yang Teng ◽  
Kai Zhang

Coal combustion is an anthropogenic source of mercury (Hg) emissions to the atmosphere. The strong toxicity and bioaccumulation potential have prompted attention to the control of mercury emissions. Pyrolysis has been regarded as an efficient Hg removal technology before coal combustion and other utilization processes. In this work, the Hg speciation in coal and its thermal stability were investigated by combined sequential chemical extraction and temperature programmed decomposition methods; the effect of coal rank on Hg speciation distribution and Hg release characteristics were clarified based on the weight loss of coal; the amount of Hg released; and the emission of sulfur-containing gases during coal pyrolysis. Five species of mercury were determined in this study: exchangeable Hg (F1), carbonate + sulfate + oxide bound Hg (F2), silicate + aluminosilicate bound Hg (F3), sulfide bound Hg (F4), and residual Hg (F5), which are quite distinct in different rank coals. Generally, Hg enriched in carbonates, sulfates, and oxides might migrate to sulfides with the transformation of minerals during the coalification process. The order of thermal stability of different Hg speciation in coal is F1 < F5 < F2 < F4 < F3. Meanwhile, the release of Hg is accompanied with sulfur gases during coal pyrolysis, which is heavily dependent on the coal rank.


Molecules ◽  
2021 ◽  
Vol 26 (9) ◽  
pp. 2651
Author(s):  
Magdalena Jabłońska-Czapla ◽  
Katarzyna Grygoyć

The optimization and validation of a methodology for determining and extracting inorganic ionic Te(VI) and Te(IV) forms in easily-leached fractions of soil by Ion Chromatography-Inductively Coupled Plasma-Mass Spectrometry (IC-ICP-MS) were studied. In this paper, the total concentration of Te, pH, and red-ox potential were determined. Ions were successfully separated in 4 min on a Hamilton PRPX100 column with 0.002 mg/kg and 0.004 mg/kg limits of detection for Te(VI) and Te(IV), respectively. Soil samples were collected from areas subjected to the influence of an electrowaste processing and sorting plant. Sequential chemical extraction of soils showed that tellurium was bound mainly with sulphides, organic matter, and silicates. Optimization of soil extraction allowed 20% average extraction efficiency to be obtained, using 100 mM citric acid as the extractant. In the tested soil samples, both tellurium species were present. In most cases, the soils contained a reduced Te form, or the concentrations of both species were similar.


Energies ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3119
Author(s):  
Yinjiao Su ◽  
Xuan Liu ◽  
Yang Teng ◽  
Kai Zhang

Mercury (Hg) is a toxic trace element emitted from coal conversion and utilization. Samples with different coal ranks and gangue from Ningwu Coalfield are selected and investigated in this study. For understanding dependence of mercury distribution characteristics on coalification degree, Pearson regression analysis coupled with Spearman rank correlation is employed to explore the relationship between mercury and sulfur, mercury and ash in coal, and sequential chemical extraction method is adopted to recognize the Hg speciation in the samples of coal and gangue. The measured results show that Hg is positively related to total sulfur content in coal and the affinity of Hg to different sulfur forms varies with the coalification degree. Organic sulfur has the biggest impact on Hg in peat, which becomes weak with increasing the coalification degree from lignite to bituminous coal. Sulfate sulfur is only related to Hg in peat or lignite as little content in coal. However, the Pearson linear correlation coefficients of Hg and pyritic sulfur are relatively high with 0.479 for lignite, 0.709 for sub-bituminous coal and 0.887 for bituminous coal. Hg is also related to ash content in coal, whose Pearson linear correlation coefficients are 0.504, 0.774 and 0.827 respectively, in lignite, sub-bituminous coal and bituminous coal. Furthermore, Hg distribution is directly depended on own speciation in coal. The total proportion of F2 + F3 + F4 is increased from 41.5% in peat to 87.4% in bituminous coal, but the average proportion of F5 is decreased from 56.8% in peat to 12.4% in bituminous coal. The above findings imply that both Hg and sulfur enrich in coal largely due to the migration from organic state to inorganic state with the increase of coalification degree in Ningwu Coalfield.


Polar Record ◽  
2021 ◽  
Vol 57 ◽  
Author(s):  
Frigga Kruse ◽  
Gary R. Nobles ◽  
Martha de Jong ◽  
Rosanne M. K. van Bodegom ◽  
G. J. M. (Gert) van Oortmerssen ◽  
...  

Abstract Arctic mining has a bad reputation because the extractive industry is often responsible for a suite of environmental problems. Yet, few studies explore the gap between untouched tundra and messy megaproject from a historical perspective. Our paper focuses on Advent City as a case study of the emergence of coal mining in Svalbard (Norway) coupled with the onset of mining-related environmental change. After short but intensive human activity (1904–1908), the ecosystem had a century to respond, and we observe a lasting impact on the flora in particular. With interdisciplinary contributions from historical archaeology, archaeozoology, archaeobotany and botany, supplemented by stable isotope analysis, we examine 1) which human activities initially asserted pressure on the Arctic environment, 2) whether the miners at Advent City were “eco-conscious,” for example whether they showed concern for the environment and 3) how the local ecosystem reacted after mine closure and site abandonment. Among the remains of typical mining infrastructure, we prioritised localities that revealed the subtleties of long-term anthropogenic impact. Significant pressure resulted from landscape modifications, the import of non-native animals and plants, hunting and fowling, and the indiscriminate disposal of waste material. Where it was possible to identify individual inhabitants, these shared an economic attitude of waste not, want not, but they did not hold the environment in high regard. Ground clearances, animal dung and waste dumps continue to have an effect after a hundred years. The anthropogenic interference with the fell field led to habitat creation, especially for vascular plants. The vegetation cover and biodiversity were high, but we recorded no exotic or threatened plant species. Impacted localities generally showed a reduction of the natural patchiness of plant communities, and highly eutrophic conditions were unsuitable for liverworts and lichens. Supplementary isotopic analysis of animal bones added data to the marine reservoir offset in Svalbard underlining the far-reaching potential of our multi-proxy approach. We conclude that although damaging human–environment interactions formerly took place at Advent City, these were limited and primarily left the visual impact of the ruins. The fell field is such a dynamic area that the subtle anthropogenic effects on the local tundra may soon be lost. The fauna and flora may not recover to what they were before the miners arrived, but they will continue to respond to new post-industrial circumstances.


Minerals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 121
Author(s):  
Noriko Yamaguchi ◽  
Toshiaki Ohkura ◽  
Atsuko Hikono ◽  
Yohey Hashimoto ◽  
Aomi Suda ◽  
...  

Global concerns for the sustainability of agriculture have emphasized the need to reduce the use of mineral fertilizer. Although phosphorus (P) is accumulated in farmland soils due to the long-term application of fertilizer, most soil P is not readily available to plants. The chemical speciation of P in soils, which comprise heterogeneous microenvironments, cannot be evaluated with a high degree of specificity using only macroscopic analyses. In this study, we investigated the distribution and speciation of P accumulated in soils by using both macro- and microscopic techniques including chemical extraction, solution and solid-state 31P NMR, bulk- and micro- P K-edge X-ray absorption near edge structure (XANES), and electron probe microanalysis (EPMA). Soil samples were collected from a field in which cabbage was cultivated under three amendment treatments: i) mineral fertilizer (NPK), ii) mineral fertilizer and compost (NPK + compost), and iii) mineral fertilizer plus compost but without nitrogen fertilizer (PK + compost). Macro-scale analyses suggested that accumulated P was predominantly inorganic P and associated with Al-bearing minerals. The repeated application of compost to the soils increased the proportion of P associated with Ca which accounted for 17% in the NPK + compost plot and 40% in the PK + compost plot. At the microscale, hot spots of P were heterogeneously distributed, and P was associated with Fe and Ca in hot spots of the NPK + compost (pH 6) and PK + compost (pH 7) treated samples, respectively. Our results indicate that application of compost contributed to creating diverse microenvironments hosting P in these soils.


1974 ◽  
Vol 22 (2) ◽  
pp. 88-103 ◽  
Author(s):  
MARSHALL R. URIST ◽  
HISASHI IWATA ◽  
STUART D. BOYD ◽  
PETER L. CECCOTTI ◽  
MARLYS OKADA ◽  
...  

Data on physicochemical conditions leading to loss of the bone morphogenetic property of bone matrix in neutral buffer solutions support the concept of an enzymic control mechanism better than a chemical blocking reaction or denaturation. The loss is associated with release of 35S-labeled constituents and not prevented by ε-amino caproic acid, an inhibitor of cathepsins. The loss is also associated with release of 35S-cysteine-labeled protein; about 60% of the yield is sustained by the addition of only 3 mmoles/liter of iodoacetic acid. A latent period of about 12 hr, decreased by extraction of bone matrix with CaCl2, is characterized by release of protein polysaccharide and other noncollagenous proteins. Release of sialic acid from the bone matrix by neuraminidase at pH 7.4 has no effect upon bone yield. At 2°C, Tris-HCl buffer or ethylenediaminetetraacetic acid extracts noncollagenous proteins without loss of bone yield; at 37°C, pH 7.4, these solutions also activate endogenous enzymes and reduce bone yield. The component of bone matrix responsible for reduction in bone yield is separable from bone matrix by extraction with phosphate buffer, by catheptic digestion of bone matrix in acidic buffer solutions, by sequential chemical extraction of noncollagenous proteins with cold slightly acidic salt solutions or by extraction-denaturation with chloroform-methanol. Detergents neither extinguish nor denature the morphogenetic property but some solubilize or extract degradative enzymes; hexodecyl trimethyl ammonium bromide, at pH 5.0, is positively charged and extracts hydrophobic proteins, including part of the bone morphogenetic property. A special selection of sulfhydryl chemical inhibitors remarkably different from the selection inhibiting known enzymes preserves the bone morphogenetic property of bone matrix; p-chloromercuribenzoate preservation is reversible by chemical reactions with cysteine. Reduction in bone yield in phosphate buffer is not attributable to a chemical block because chloroform-methanol extraction of the agent does not restore bone yield and is not attributable to denaturation because bone yield sustained by p-chloromercuribenzoate is lost by chemical reactions with cysteine. An hypothetical insoluble bone morphogenetic protein (BMP) firmly bound to collagen is degraded by a soluble neutral proteinase (BMPase). Digestion of the hypothetical BMP occurs without loss of the 640-A electron micrographic image of bone collagen, resembles tryptic digestion and is more selective as well as physiologic in action.


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