Browse
Submit Data
Databases
API
Help

Dataset Information

15 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Evaluation of Main Factors for Improvement of the Scandium Leaching Process from Russian Bauxite Residue (Red Mud) in Carbonate Media.

ABSTRACT: The carbonate leaching of scandium from the landfilled bauxite residue (red mud) of the Bogoslovsky Aluminum Plant (Russia) and samples of red mud (RM) after alkaline pretreatment has been investigated. The results of kinetic studies allowing to compare and evaluate the effectiveness of different conditions and intensification factors in the process of scandium leaching from RM in carbonate/bicarbonate media are presented. It was determined that for 2.0 mol L^-1 Na₂CO₃ leaching solution ultrasonic treatment under gas (CO₂) carbonation conditions in the pH range of 9.5-10.0 allows reducing the scandium leaching time by two times and reaching 40-45% scandium extraction. Leaching of RM in carbonate/bicarbonate media is accompanied by secondary processes (adsorption, hydrolysis, and coprecipitation) leading to a decrease in scandium extraction. The obtained results allow improving understanding of scandium chemical behavior in complex aqueous carbonate/bicarbonate systems and can be used for the optimization of the alternative carbonate process for scandium extraction from RM.

SUBMITTER: Boyarintsev AV

PROVIDER: S-EPMC8757361 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

Synthesis of Scandium Phosphate after Peroxide Assisted Leaching of Iron Depleted Bauxite Residue (Red Mud) Slags.

Project description:Anticipated future demand and limited primary sources of Sc highlight the importance of secondary Sc resources such as bauxite residue (red mud). In this study, a process route starting from red mud aiming to recover Sc as a concentrate by a combination of pyrometallurgical and hydrometallurgical processes was developed. Bauxite residue was treated in an electric arc furnace (EAF) for Fe removal as well as slag conditioning with varying flux additions and various cooling conditions. 95% of iron recovery to the metal was achieved. Resulting slags were subjected to identical H2O2 supported H2SO4 leaching conditions at 75 °C. The effect of slag mineralogy and crystallinity on the leaching efficiencies were investigated using XRD and QEMSCAN analysis. As a result of the highly amorphous nature of acidic slags, maximum of 72% Sc leaching was obtained. For leached slags, water quenched basic slag was found to be the most promising condition resulting in an extreme Sc leaching yield of 97% and this slag was selected for the further Sc precipitation. High impurity removal rates and selective Sc separation were achieved with a triple-stage successive precipitation to synthesize a Sc concentrate. Starting from EAF treatment followed by leaching and precipitation, 85% of the initial Sc in the red mud was successfully recovered as Sc phosphate.

| S-EPMC6694154 | biostudies-literature

Leaching of copper and nickel in soil-water systems contaminated by bauxite residue (red mud) from Ajka, Hungary: the importance of soil organic matter.

Project description:Red mud is a highly alkaline (pH >12) waste product from bauxite ore processing. The red mud spill at Ajka, Hungary, in 2010 released 1 million m(3) of caustic red mud into the surrounding area with devastating results. Aerobic and anaerobic batch experiments and solid phase extraction techniques were used to assess the impact of red mud addition on the mobility of Cu and Ni in soils from near the Ajka spill site. Red mud addition increases aqueous dissolved organic carbon (DOC) concentrations due to soil alkalisation, and this led to increased mobility of Cu and Ni complexed to organic matter. With Ajka soils, more Cu was mobilised by contact with red mud than Ni, despite a higher overall Ni concentration in the solid phase. This is most probably because Cu has a higher affinity to form complexes with organic matter than Ni. In aerobic experiments, contact with the atmosphere reduced soil pH via carbonation reactions, and this reduced organic matter dissolution and thereby lowered Cu/Ni mobility. These data show that the mixing of red mud into organic rich soils is an area of concern, as there is a potential to mobilise Cu and Ni as organically bound complexes, via soil alkalisation. This could be especially problematic in locations where anaerobic conditions can prevail, such as wetland areas contaminated by the spill.

| S-EPMC4490175 | biostudies-literature

Separation of Scandium from Hydrochloric Acid-Ethanol Leachate of Bauxite Residue by a Supported Ionic Liquid Phase.

Project description:Solvometallurgy is a new branch of extractive metallurgy in which green organic solvents are used instead of aqueous solutions to improve selectivity in separation processes. In the present study, nonaqueous leaching of a Greek bauxite residue (BR) was performed and scandium was separated from other elements in the leachate by column chromatography. At first, the selectivity of sorbents for scandium(III) over iron(III) was tested in batch mode using various organic solvents. The following three sorbents were tested: (1) a carboxylic acid-functionalized supported ionic liquid phase (SILP), (2) silica (SiO2), and (3) silica functionalized with ethylenediaminetetraacetic acid (SiO2-TMS-EDTA). The best separation of scandium and iron was achieved from ethanolic solution by the SILP. The BR was then leached with 0.7 mol L-1 HCl in ethanol or in water. The leaching efficiency of scandium with both lixiviants was similar. However, much less sodium was leached, and silica remained in solution when leaching was performed with the ethanolic lixiviant. By using ethanol as opposed to water, the serious drawback of silica gel formation that is taking place in the aqueous leachate of BR was circumvented. The sorption preference of the SILP for metal ions in the ethanolic leachate was partly reversed compared to the aqueous leachate. Iron was separated from other metals of the ethanolic BR leachate by a simple elution with ethanol. The formation of the anionic tetrachloroferrate(III) complex, [FeCl4]-, enabled the selective elution. This complex was not observed in the aqueous leachate of BR. Scandium was separated from the vast majority of other components of the BR by elution with 0.1 mol L-1 H3PO4.

| S-EPMC7499406 | biostudies-literature

Neutralization and Improvement of Bauxite Residue by Saline-Alkali Tolerant Bacteria.

Project description:The high salt-alkalinity of bauxite residue (BR) hinders plant growth and revegetation of bauxite residue disposal areas (BRDA), which cause serious potential environmental and ecological risks. Bioneutralization is a promising method for improving the properties of BR and plant colonization. In the present study, a strong saline-alkali tolerant bacteria (ZH-1) was isolated from aged BR and identified as Bacillus sp. The medium of ZH-1 was optimized by orthogonal tests, and ZH-1 could decrease the medium pH from 11.8 to 6.01 (agitated culture) and 6.48 (static culture) by secretion of citric acid, oxalic acid and tartaric acid. With the inoculation of ZH-1, the pH of BR decreased from 11.6 to 8.76, and the water-soluble salt in BR increased by 68.11%. ZH-1 also changed the aggregate size distribution of BR, the mechanical-stable aggregates and water-stable aggregates increased by 18.76% and 10.83%, respectively. At the same time, the stability of the aggregates obviously increased and the destruction rate decreased from 94.37% to 73.46%. In addition, the microbial biomass carbon increased from 425 to 2794 mg/kg with the inoculation of ZH-1. Bacterial community analysis revealed that Clostridia, Bacilli, Gammaproteobacteria, Betaproteobacteria and Alphaproteobacteria were the main classes in the naturalized BR, and the inoculation of ZH-1 increased the diversity of bacteria in the BR. Overall, ZH-1 has great potential for neutralization and improvement the properties of BR and may be greatly beneficial for the revegetation of BRDA.

| S-EPMC9517105 | biostudies-literature

The role of nano-perovskite in the negligible thorium release in seawater from Greek bauxite residue (red mud).

Project description:We present new data about the chemical and structural characteristics of bauxite residue (BR) from Greek Al industry, using a combination of microscopic, analytical, and spectroscopic techniques. SEM-EDS indicated a homogeneous dominant "Al-Fe-Ca-Ti-Si-Na-Cr matrix", appearing at the microscale. The bulk chemical analyses showed considerable levels of Th (111 μg g(-1)), along with minor U (15 μg g(-1)), which are responsible for radioactivity (355 and 133 Bq kg(-1) for (232)Th and (238)U, respectively) with a total dose rate of 295 nGy h(-1). Leaching experiments, in conjunction with SF-ICP-MS, using Mediterranean seawater from Greece, indicated significant release of V, depending on S/L ratio, and negligible release of Th at least after 12 months leaching. STEM-EDS/EELS &HR-STEM-HAADF study of the leached BR at the nanoscale revealed that the significant immobility of Th(4+) is due to its incorporation into an insoluble perovskite-type phase with major composition of Ca(0.8)Na(0.2)TiO3 and crystallites observed in nanoscale. The Th L(III)-edge EXAFS spectra demonstrated that Th(4+) ions, which are hosted in this novel nano-perovskite of BR, occupy Ca(2+) sites, rather than Ti(4+) sites. That is most likely the reason of no Th release in Mediterranean seawater.

| S-EPMC4761986 | biostudies-literature

bauxite residue eco-engineering

Project description:bauxite residue eco-engineering Raw sequence reads

| PRJNA1002762 | ENA

The potential of Hungarian bauxite residue isolates for biotechnological applications.

Project description:Bauxite residue (red mud) is considered an extremely alkaline and salty environment for the biota. We present the first attempt to isolate, identify and characterise microbes from Hungarian bauxite residues. Four identified bacterial strains belonged to the Bacilli class, one each to the Actinomycetia, Gammaproteobacteria, and Betaproteobacteria classes, and two to the Alphaproteobacteria class. All three identified fungi strains belonged to the Ascomycota division. Most strains tolerated pH 8-10 and salt content at 5-7% NaCl concentration. Alkalihalobacillus pseudofirmus BRHUB7 and Robertmurraya beringensis BRHUB9 can be considered halophilic and alkalitolerant. Priestia aryabhattai BRHUB2, Penicillium chrysogenum BRHUF1 and Aspergillus sp. BRHUF2 are halo- and alkalitolerant strains. Most strains produced siderophores and extracellular polymeric substances, could mobilise phosphorous, and were cellulose degraders. These strains and their enzymes are possible candidates for biotechnological applications in processes requiring extreme conditions, e.g. bioleaching of critical raw materials and rehabilitation of alkaline waste deposits.

| S-EPMC10788403 | biostudies-literature

Recovery of scandium and neodymium from blast furnace slag using acid baking-water leaching.

Project description:The current study puts the emphasis on developing a pyro-hydrometallurgical process, called acid baking-water leaching, to recover scandium and neodymium from blast furnace slag produced by the ironmaking industry. In this process, the feed is mixed with concentrated sulfuric acid, digested at 200-400 °C, and leached in water at ambient conditions. This process offers several advantages including less acidic waste generation and rapid kinetics. With fundamental investigations into the digestion mechanism, acid to slag mass ratio and baking temperature are determined to have the most significant positive and negative impacts, respectively. At low acid to slag ratio, the silicate bearing phases in the feed do not digest, resulting in low extraction. At 200 °C baking temperature, a hydrated aluminum sulfate ((Al(H2O)6)2(SO4)3(H2O)4.4) phase with weak hydrogen bonds is formed that leaches in water rapidly (<10 min); while at 400 °C, Al2(SO4)3 with strong ionic bonds is formed that leaches at slower kinetics (>4 h). Fundamental investigations into the water leaching process indicate that the diffusion of water through the firm solid product (ash layer) is the rate determining step. We expect the results of this study would help enable valorization of industrial byproducts, in particular ironmaking slag.

| S-EPMC9056533 | biostudies-literature

Fish as major carbonate mud producers and missing components of the tropical carbonate factory.

Project description:Carbonate mud is a major constituent of recent marine carbonate sediments and of ancient limestones, which contain unique records of changes in ocean chemistry and climate shifts in the geological past. However, the origin of carbonate mud is controversial and often problematic to resolve. Here we show that tropical marine fish produce and excrete various forms of precipitated (nonskeletal) calcium carbonate from their guts ("low" and "high" Mg-calcite and aragonite), but that very fine-grained (mostly < 2 ?m) high Mg-calcite crystallites (i.e., > 4 mole % MgCO(3)) are their dominant excretory product. Crystallites from fish are morphologically diverse and species-specific, but all are unique relative to previously known biogenic and abiotic sources of carbonate within open marine systems. Using site specific fish biomass and carbonate excretion rate data we estimate that fish produce ?6.1 × 10(6) kg CaCO(3)/year across the Bahamian archipelago, all as mud-grade (the < 63 ?m fraction) carbonate and thus as a potential sediment constituent. Estimated contributions from fish to total carbonate mud production average ?14% overall, and exceed 70% in specific habitats. Critically, we also document the widespread presence of these distinctive fish-derived carbonates in the finest sediment fractions from all habitat types in the Bahamas, demonstrating that these carbonates have direct relevance to contemporary carbonate sediment budgets. Fish thus represent a hitherto unrecognized but significant source of fine-grained carbonate sediment, the discovery of which has direct application to the conceptual ideas of how marine carbonate factories function both today and in the past.

| S-EPMC3054004 | biostudies-literature

The origin of carbonate mud and implications for global climate.

Project description:Carbonate mud represents one of the most important geochemical archives for reconstructing ancient climatic, environmental, and evolutionary change from the rock record. Mud also represents a major sink in the global carbon cycle. Yet, there remains no consensus about how and where carbonate mud is formed. Here, we present stable isotope and trace-element data from carbonate constituents in the Bahamas, including ooids, corals, foraminifera, and algae. We use geochemical fingerprinting to demonstrate that carbonate mud cannot be sourced from the abrasion and mixture of any combination of these macroscopic grains. Instead, an inverse Bayesian mixing model requires the presence of an additional aragonite source. We posit that this source represents a direct seawater precipitate. We use geological and geochemical data to show that "whitings" are unlikely to be the dominant source of this precipitate and, instead, present a model for mud precipitation on the bank margins that can explain the geographical distribution, clumped-isotope thermometry, and stable isotope signature of carbonate mud. Next, we address the enigma of why mud and ooids are so abundant in the Bahamas, yet so rare in the rest of the world: Mediterranean outflow feeds the Bahamas with the most alkaline waters in the modern ocean (>99.7th-percentile). Such high alkalinity appears to be a prerequisite for the nonskeletal carbonate factory because, when Mediterranean outflow was reduced in the Miocene, Bahamian carbonate export ceased for 3-million-years. Finally, we show how shutting off and turning on the shallow carbonate factory can send ripples through the global climate system.

| S-EPMC9618081 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data