Study of iron-based metal–organic framework for selenite removal …
The whitish–yellow obtained product, i.e., MIL-53 (Fe) was then recovered and used for carrying out all selenium removal experimentation. Selenium removal study Adsorption experiment. About 0.1-mg/mL adsorbent dosage, i.e., 20 mg of MIL-53 (Fe) was ultrasonicated in 200-mL solution with different selenite concentrations. About 7 mL of …
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Methods for selenium removal from contaminated …
Here, we review methods for selenium removal from water, wastewater, and industrial effluents. Technologies are based on zero-valent iron, iron-oxy-hydroxides, supported materials, nanofiltration ...
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Review on environmental selenium: Occurrence, public …
A follow-up pilot-scale study done by Cantafio et al. (1996) used a packed-bed bioreactor inoculated with the bacterium Thauera selenatis for the removal of selenium from the drainage wastewater and achieved a removal rate and performed a complete conversion of selenate to elemental selenium. The removal of selenium was …
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Selenium: environmental significance, pollution, and biological
Selenium (Se 79 34) is an essential element in living organisms.It is the 30th most abundant naturally occurring metalloid element on the Earth's crust. Selenium is present in the earth's crust at an estimated amount of 0.05–0.5 mg Se kg − 1 (Lemly, 2004), with total selenium concentrations in rocks amounting to 40% of the total earth's crust …
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Selenium Removal Using a Moving Bed Biofilm Reactor
An MBBR is a biological method to remove selenium that can operate with the same support material for over 20 years, while granulated activated carbon in other biological methods may need to be replaced regularly. The MBBR does not require back-washing; it can tolerate high suspended solids concentrations in the feed and is not …
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Selenium removal from petroleum refinery wastewater …
Selenium removal efficiency vs time for a current density of 153.4 A m −2. Other authors have reported selenium removal efficiencies of about 90% the treatment of wastewater from copper industry by EC with an initial concentration of selenium of 5 mg L −1 using a treatment time of 20 min and a current density 50% lower than that used ...
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Phillips 66's Selenium Removal Technology
Existing technologies for selenium removal are complex, costly and usually inadequate, especially considering the likelihood that regulations controlling selenium discharge will continue to tighten. Phillips 66's SeRT ® technology is a simple, fixed-bed process that looks and runs like many other refinery processes, SeRT ® technology is not ...
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Dissolved‑selenium removal using magnetic nanoparticles: …
Adsorbents as magnetic nanomaterials used for dissolved‑selenium removal were summarized in this review. Section snippets Magnetic nanoparticles. Nanotechnology is a highly concerned technology with fast development [33]. MNPs are nano-scale particles having magnetic properties that facilitate the reuse of the sorbents, which have been ...
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Electrochemical Evaluation of Selenium (IV) Removal from …
The removal of selenium from superficial and waste water is a worldwide problem. The maximum limit according to the World Health Organization (WHO) for the selenium in the water is set at a concentration of 10 μg/L. Carbon based adsorbents have attracted much attention and recently demonstrated promising performance in removal …
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A Non-Biological Process for Selenium Removal from …
A Non-Biological Process for Selenium Removal from Industrial Wastewater. Posted by ChemTreat On 07/27/2020. One of the primary, and heretofore costly-to-remove, contaminants in coal-fired power plant wastewater streams is selenium. Concerns now abound regarding selenium toxicity in other streams, including mine …
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A critical review on selenium removal capacity from water …
Anthropogenic-driven selenium (Se) contamination of natural waters has emerged as severe health and environmental concern. Lowering Se levels to safe limits of 40 μg-L −1 (recommended by WHO) presents a critical challenge for the scientific community, necessitating reliable and effective methods for Se removal. The primary …
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A critical review on Selenium removal capacity from water …
Here, we review methods for selenium removal from water, wastewater, and industrial effluents. Technologies are based on zero-valent iron, iron-oxy-hydroxides, supported materials, nanofiltration ...
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Selenium removal from water using adsorbents: A critical …
Selenium (Se) has become an increasingly serious water contamination concern worldwide. It is an essential micronutrient for humans and animals, however, can be extremely toxic if taken in excess. Sorption can be an effective treatment for Se removal from a wide range of water matrices. However, des …
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Selenium Water Treatment
In selenium water treatment, selenite and selenate are reduced to insoluble selenium that is removed along with biomass and feed suspended solids by downstream liquid/solids separation. This process is effectively used for selenium removal from mining wastewater and other difficult industrial applications.
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Selenium Removal from Wastewater by Microbial …
Selenium removal from wastewater mainly involves microbial reduction of water-soluble Se oxyanions (SeO 3 2− and SeO 4 2−) to water-insoluble elemental selenium (Se 0). The microbial reduction can be enhanced with additional sources of electron donors such as sugar, organic acids, humic substances, or alcohol [ 10 ].
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Kinetics study of selenium removal from copper …
The solution to the removal circuit has a typical composition of 100 g/L copper sulfate, 125 g/L sulfuric acid and, reporting at most 100 mg/L of selenium. It was reported by Qin (2005) that 20 to 40% of the selenium to …
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Selenium Removal Key to Water Reuse
USBR investigated selenium removal technologies from 2003 to 2006. Investigations included laboratory bench-testing and field pilot-testing to reduce selenium concentrations in local agricultural drainage water near Firebaugh, California. USBR issued a Record of Decision in 2007, which selected a drainage alternative based upon a reverse ...
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Selenium Removal by SMI | Prima Environmental
The wastewaters were used "as received" or pre-treated. Tests ran for about 120 bed volumes with an empty bed contact time (EBCT) of 10-20 minutes. Selenium removal efficiency was highly dependent on the wastewater, ranging from poor removal to removal (see Table). Based on the results of the screening level tests, field pilot tests ...
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Treatment technologies for selenium contaminated water: A …
A comprehensive literature review is conducted to analyze various studies that have explored the use of modified biochars, iron oxides, and other non-conventional biosorbents for selenium removal. The assessed biosorbents include biomass, microalgae-based, alginate compounds, peats, chitosan, and biochar/modified biochar …
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Selenium contaminated waters: An overview of analytical …
Selenium removal from aqueous medium can also be achieved using biological methods. In a first approach, these kinds of methods appear to be attractive, low-cost, and eco-friendly, since few chemicals are required. Biological volatilization can occur in soils, sediments and water. It is based on the natural ability of bacteria, fungi and …
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Application of Fe-biochar composites for selenium (Se+6) removal …
Selenium in selenite (SeO 3 2−) is in the +4 oxidation state and it can be removed by conventional water treatment. Whereas, a more complex approach is necessary for the removal of selenium in the +6 state form, as selenate (SeO 4 2−) (Etteieb et al., 2020). One method for selenate removal is by reduction through the use …
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Recent advances in technologies for removal and …
... Examples of physical treatment are membrane separation technologies such as nanofiltration (NF) and reverse osmosis (RO) (Ali and Shrivastava 2021; …
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Selenium Removal from Industrial Wastewater
Vladimir Djukanovic. Photo by NOAA on Unsplash. Coal-fired power plant outside of Fairbanks, Ak. View Image Gallery. A critical …
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A Bibliometric Analysis of Research on Selenium in Drinking …
The lack of terms directly related to possible technologies for selenium removal from water during the analysis of the most frequently used keywords was at least partially solved when the cluster Adsorption was examined (Figures S7 and S9). This cluster appeared in the third subperiod (2012–2019) and had continuity until the last …
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Biological Removal of Selenate and Selenite from …
Several conventional bioreactor systems can be used to remove selenate and selenite from wastewater and form selenium nanoparticles. However, the selenium …
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Methods for selenium removal from contaminated waters: a …
An iron coprecipitation unit at the industrial scale. This technology is a well-known and well-accepted chemical process for the removal of metals and metalloids, including the removal of selenium and arsenic, and has been widely implemented in various industries; briefly, a ferric salt is added to the effluent, forming an amorphous iron oxyhydroxide precipitate; …
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Selenium Removal from Industrial Wastewater | Water …
The data from another bench-scale test outlines an example of selenium reduction potential from oil refinery wastewater: 24.4 μg/L from untreated wastewater; . 2.5 μg/L from treated wastewater. In many states (California, for example), groundwater is being regulated for selenium discharge, creating challenges for industrial facilities.
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Selenium removal from petroleum refinery wastewater …
For this purpose, a batch airlift reactor with air stirring was used. The sacial electrodes were made of iron to generate the necessary ferrous ions for the process. The results indicated a selenium removal of 90% from the wastewater after 6 h of treatment, achieving a decrease in concentration from 0.30 mg L-1 to 0.03 mg L-1. The …
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Dissolved‑selenium removal using magnetic nanoparticles: …
Schematic of dissolved‑selenium removal using nano-magnetic particles. 2.1. Nanosized zero-valent iron (nZVI) Zero-valent iron (ZVI) is a ubiquitous substance in nature, which can be used as a removal agent for a variety of pollutants [38, 39].
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Selenium Removal from Water and Wastewater by …
The Se removal efficacy can be enhanced by: 1) Combining biological treatment with chemical or physical methods to optimize Se removal and to ensure …
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