Chromite ore processing residue (COPR), derived from the so-called high lime processing of chromite ore, contains high levels of Cr(III) and Cr(VI) and has a pH between 11 and 12. Ferrous sulfate, which is used for remediation of Cr(VI) contamination in wastewater and soils via reduction to Cr(III) and subsequent precipitation of iron(III)/chromium(III) hydroxide, has also been proposed for rem...

nowdays,  iron  nanoparticles  due  to  their  unique  characteristics  are used  in  all  of  sciences  and  technology.  these  nano  particles  due  to their  electrical, magnetic,  optical  and  catalytic  properties  and  having high  area  and  activity  that  is  promped  by  their  small  size  and most importantly  many  scientists  from  the  entire  world  are  interested  in their  ...

The biological and chemical potential for electron shuttling via humic acids was evaluated by analyzing the depth distribution of humic-acid-reducing and iron-reducing bacteria in a freshwater sediment, and correlating it to the redox characteristics of humic acids and iron. Physicochemical analysis of profundal sediments of Lake Constance revealed a distinct stratification, with oxygen respira...

The filtrate obtained by interacting a known amount of rice husk with deionised, Milli-Q water was assessed as a carbon source and nutrient medium for the growth of Desulfotomaculum nigrificans, a typical sulfate-reducing bacterium. The filtrate contained essential growth constituents such as magnesium, potassium, phosphorous apart from calcium, sodium, chloride and sulfate ions. Based on the 1...

Hydrometallurgical leaching solutions are often rich in iron, which was traditionally considered a major impurity. However, iron can be selectively separated and recovered by applying appropriate solvent extraction stripping techniques, the resulting valorized for synthesis of high-added-value products, such as magnetic oxide nanoparticles (mIONPs). The aim this study to synthesize high-quality...

We develop a relationship between the sulfate-methane transition (SMT) and average gas hydrate saturation (AGHS) for systems dominated by methane migration from deeper sources. The relationship is explained by a onedimensional numerical model that simulates gas hydrate accumulation in marine sediments. Higher methane fluxes result in shallow SMT depths and high AGHS, while lower methane fluxes ...

The Mars Global Surveyor, Mars Exploration Rover, and Mars Express missions have stimulated considerable thinking about the surficial geochemical evolution of Mars. Among the major recent mission findings are the presence of jarosite (a ferric sulfate salt), which requires formation from an acid-sulfate brine, and the occurrence of hematite and goethite on Mars. Recent ferric iron models have l...

â  abstract: in this work, the kinetics of ethane hydrate formation has been studied experimentally and a kinetic model based on chemical affinity has been described for predicting the hydrate growth process in the stirred batch reactor at a constant volume. the experiments were done with both pure water and aqueous solution of sodium dodecyl sulfate (sds). the effect of sds on formation kineti...

It has long been hypothesized that acids formed from anthropogenic pollutants and natural emissions dissolve iron (Fe) in airborne particles, enhancing the supply of bioavailable Fe to the oceans. However, field observations have yet to provide indisputable evidence to confirm this hypothesis. Single-particle chemical analysis for hundreds of individual atmospheric particles collected over the ...

The chemical stability of iron corrosion scales and the microbial community of biofilm in drinking water distribution system (DWDS) can have great impact on the iron corrosion and corrosion product release, which may result in "red water" issues, particularly under the situation of source water switch. In this work, experimental pipe loops were set up to investigate the effect of sulfate on the...