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LONG-TERM stability of arsenic in iron amended contaminated soil
2021
Kumpiene, Jurate | Carabante, Ivan | Kasiuliene, Alfreda | Austruy, Annabelle | Mench, Michel | Luleå University of Technology = Luleå Tekniska Universitet (LUT) | Institut Ecocitoyen pour la Connaissance des Pollutions [Fos-sur-Mer] | Biodiversité, Gènes & Communautés (BioGeCo) ; Université de Bordeaux (UB)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | The La Combe de Saut experiment was funded by ADEME and the LIFE project DIFPOLMINE. The Reppel experiment was set up under the EU FP5 Phytorehab project. Experiments in Sweden were financed by the Swedish Research Council FORMAS and European Union Structural Funds and New Objective 1, North Sweden Soil Remediation Center (MarksaneringsCentrum Norr - MCN). Stanford Synchrotron Radiation Lightsource is acknowledged for granting our beamtime proposal (4663) under which X-Ray absorption measurements presented in this work were performed.
International audience | This study aimed at elucidating the long-term efficiency of soil remediation where chemical stabilization of arsenic (As) contaminated soil using zerovalent iron (Fe) amendments was applied. A combination of chemical extraction and extended X-Ray absorption fine structure (EXAFS) spectroscopy technique was applied on soils collected from five laboratory and field experiments in Sweden and France. All soils were treated with 1 wt% of zerovalent Fe grit 2e15 years prior to the sampling. The results indicate that all studied soils, despite the elapsed time since their amendment with Fe grit, had substantial amounts of ferrihydrite and/or lepidocrocite. These metastable and the most reactive Fe (oxyhydr)oxides (mainly ferrihydrite) were still present in substantial amounts even in the soil that was treated 15 years prior to the sampling and contributed most to the As immobilisation in the amended soils. This increases confidence in the long-term efficiency of As immobilisation using zerovalent Fe amendments. Both applied methods, sequential extraction and EXAFS, were in line for most of the samples in terms of their ability to highlight As immobilisation by poorly crystalline Fe phases.
Mostrar más [+] Menos [-]Immobilization of azo-dyes for optical detection of metal ions in water: reaction with Pd(II) [palladium]
2001
Savic, J. | Vasic, V. (Institut za nuklearne nauke "Vinca", Beograd (Yugoslavia). Laboratorija za fizicku hemiju)
The reaction of Pd(II) with 1,8-dihydroxy-2-(pyrazol-5-ylazo)-naphthalen-3,6-disulphonic acid immobilized by physical sorption onto Dowex 1-X8 ion-exchange resin was investigated with the aim to develop the sorption-spectroscopic test method for the detection of low Pd(II) concentrations in water. The resin phase absorption spectra of the reagent and its Pd(II) complex were followed. The immobilized reagent has the spectral characteristics similar to those in the water and forms with Pd(II) 1:1 complex with the absorption maximum at 650 nm. Parameters, such as pH, wavelength and contact time have been optimized for a given amount of the sorbed reagent. The experimental conditions for the linear dependence of absorbance vs. Pd(II) concentration have been determined.
Mostrar más [+] Menos [-]Development of multifarious carrier materials and impact conditions of immobilised microbial technology for environmental remediation: A review
2022
Gong, You-Zi | Niu, Qiu-Ya | Liu, Yun-Guo | Dong, Jie | Xia, Meng-Meng
Microbial technology is the most sustainable and eco-friendly method of environmental remediation. Immobilised microorganisms were introduced to further advance microbial technology. In immobilisation technology, carrier materials distribute a large number of microorganisms evenly on their surface or inside and protect them from external interference to better treat the targets, thus effectively improving their bioavailability. Although many carrier materials have been developed, there have been relatively few comprehensive reviews. Therefore, this paper summarises the types of carrier materials explored in the last ten years from the perspective of structure, microbial activity, and cost. Among these, carbon materials and biofilms, as environmentally friendly functional materials, have been widely applied for immobilisation because of their abundant sources and favorable growth conditions for microorganisms. The novel covalent organic framework (COF) could also be a new immobilisation material, due to its easy preparation and high performance. Different immobilisation methods were used to determine the relationship between carriers and microorganisms. Co-immobilisation is particularly important because it can compensate for the deficiencies of a single immobilisation method. This paper emphasises that impact conditions also affect the immobilisation effect and function. In addition to temperature and pH, the media conditions during the preparation and reaction of materials also play a role. Additionally, this study mainly reviews the applications and mechanisms of immobilised microorganisms in environmental remediation. Future development of immobilisation technology should focus on the discovery of novel and environmentally friendly carrier materials, as well as the establishment of optimal immobilisation conditions for microorganisms. This review intends to provide references for the development of immobilisation technology in environmental applications and to further the improve understanding of immobilisation technology.
Mostrar más [+] Menos [-]LONG-TERM stability of arsenic in iron amended contaminated soil
2021
Kumpiene, Jurate | Carabante, Ivan | Kasiuliene, Alfreda | Austruy, Annabelle | Mench, Michel
This study aimed at elucidating the long-term efficiency of soil remediation where chemical stabilization of arsenic (As) contaminated soil using zerovalent iron (Fe) amendments was applied. A combination of chemical extraction and extended X-Ray absorption fine structure (EXAFS) spectroscopy technique was applied on soils collected from five laboratory and field experiments in Sweden and France. All soils were treated with 1 wt% of zerovalent Fe grit 2–15 years prior to the sampling. The results indicate that all studied soils, despite the elapsed time since their amendment with Fe grit, had substantial amounts of ferrihydrite and/or lepidocrocite. These metastable and the most reactive Fe (oxyhydr)oxides (mainly ferrihydrite) were still present in substantial amounts even in the soil that was treated 15 years prior to the sampling and contributed most to the As immobilisation in the amended soils. This increases confidence in the long-term efficiency of As immobilisation using zerovalent Fe amendments. Both applied methods, sequential extraction and EXAFS, were in line for most of the samples in terms of their ability to highlight As immobilisation by poorly crystalline Fe phases.
Mostrar más [+] Menos [-]Evaluation of hydroxyapatite as a metal immobilizing soil additive for the remediation of polluted soils. Part 1. Influence of hydroxyapatite on metal exchangeability in soil, plant growth and plant metal accumulation
1999
Boisson, J. | Ruttens, A. | Mench, M. | Vangronsveld, J. (INRA Bordeaux Aquitaine Research Center, Agronomy Unit, BP 81, F-33883 Villenave d'Ornon (France))
Effects of nitrogen deposition on tree growth and soil nutrients in boreal scots pine stands
1998
Nissinen, A. | Hari, P. (Department of Forest Ecology, P.O. Box 24, University of Helsinki, 00014 Helsinki (Finland))
Reclamation of a bare industrial area contaminated by non-ferrous metals: physico-chemical and biological evaluation of the durability of soil treatment and revegetation
1996
Vangronsveld, J. | Colpaert, J.V. | Tichelen, K.K. van (Limburgs Universitair Centrum, Universitaire Campus, B-3590, Diepenbeek (Belgium))
Reclamation of a bare industrial area contaminated by non-ferrous metals: in situ metal immobilization and revegetation
1995
Vangronsveld, J. | Van Assche, F. | Clijsters, H. (Limbergs Universitair Centrum, Universitaire Campus, 3590 Diepenbeek (Belgium))
Turnover of carbon and nitrogen in coniferous forest soils of different N-status and under different 15NH4-N application rate
1998
Sjoberg, R.M. | Persson, T. (Department of Ecology and Environmental Research, Swedish University of Agricultural Sciences, P.O. Box 7072, S-750 07 Uppsala (Sweden))
Development of bioreactors for denitrification with immobilized cells
1997
Matsumura, M. | Tsubota, H. | Ito, O. | Wang, P.C. | Yasuda, K. (University of Tsukuba, Tsukuba, Ibaraki (Japan). Inst. of Applied Biochemistry)
Macro-porous cellulose carrier (AQUACEL) was applied for immobilization of denitrifying bacteria to develop a practical nitrogen removal system with high performance. When the immobilized cell was applied to denitrification under high nitrogen loading rate, flotation of carriers caused by the evolution of nitrogen gas resulted. To counter the problem of carrier flotation, new reactors using hydrodynamic jet flow and centrifugal force were developed. These new reactors distributed homogeneously the floating carriers, and complete denitrification was obtained even at high loading rate of 20 kg N/cu m-carrier/d. This AQUACEL system was effectively applied to denitrification of wastewater discharged from an eletroplating factory
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