This work aims to study the removal of Cu(II) and Cr(VI) from aqueous solutions with commercial coffee wastes. Materials with no further treatment such as coffee residues from café may act as adsorbents for the removal of Cu(II) and Cr(VI). Equilibrium data were successfully fitted to the Langmuir, Freundlich and Langmuir-Freundlich model (L-F). The maximum adsorption capacity of the coffee res...

In this study, a strain of lactic acid bacteria Streptococcus salivarius was studied for its capacity to remove hexavalent chromium (Cr (VI)) from a liquid medium and to form biofilm. Both properties are useful for using the strain in bioremediation of metal-contaminated effluents. For biofilm formation capacity, three methods were used: the tube method (TM), the Congo red agar method (CRA) and...

Alternative adsorbents like Activated charcoal, modified activated charcoal, wheat bran, activated neem leaf powder and groundnut shell powder were used as adsorbents for effective removal of Cr (VI) ions and thus a comparative study between the adsorbents are presented. Waste water containing Cr (VI) ions was treated with all adsorbents for a calculated amount of time. Further, filtration was ...

Strong anion exchange resin (Spectra/Gel IE 1x8) has been investigated as adsorbent for the efficient removal of Cr(VI) ions from synthetic wastewater solutions. Batch experiments were conducted with initial Cr(VI) ions concentration ranging from 25-300 mg/L. Different parameters influencing Cr(VI) adsorption process such as; solution pH, Cr(VI) and adsorbent concentration and contact time were...

objective: hexavalent chromium [cr (vi)] compounds are well-known environmental contaminants  generated from industrial processes. several studies have reported the harmful effects of cr (vi) on different organs, however, little is known about neurotoxic effects of cr (vi). the aim of this study is to investigate the toxic effects of cr (vi) on pc12 cells. methods: pc12 cells were cultured foll...

The goal of the present work is the design of a material that may act as a robust and low cost biosorbent fortreatment of wastewater with low concentration of metals ions, such as chromium and iron. The removal ofmetallic ions from binary aqueous solutions of Fe(III)/Cr(III) and Fe(III)/Cr(VI), by an Arthrobacter viscosusbiofilm supported on NaY zeolite was investigated. Experiments...

This paper deals with Cr(VI) ion removal from water, by micro-alloyed aluminium composite (MAlC), under flow conditions. In a water environment the MAlC acts as a strong reducing agent. Dissolving it in water is accompanied by the generation of Al(III) ions and reduction of water to H 2 , with OH ions. The final product is insoluble Al(OH) 3 . A series of Cr(VI) model solutions, with initial pH...

the potential of heat inactivated saccharomyces cerevisiae in the bioremoval and reduction ofcr (vi) ions from wastewaters was evaluated in terms of metal uptake in time and at equilibrium, andbiosorption efficiency, by varying ph, biosorbent doses, contact time and temperature, in batch mode. during the sorption process, the heat inactivated biomass of the yeast saccharomyces cerevisiae is cap...

We propose a method to enhance the fuel cell efficiency with the simultaneous removal of toxic heavy metal ions. Carbon monoxide (CO), an intermediate of methanol oxidation that is primarily responsible for Pt catalyst deactivation, can be used as an in-situ reducing agent for hexavalent chromium (Cr (VI)) with reactivating the CO-poisoned Pt catalyst. Using electro-oxidation measurements, the ...

Inorganic Cr(III) and Cr(VI) have contrasting biological, geochemical and toxicology effects. Cr(III) is considered as an essential species for the proper functioning of living organisms but Cr(VI) is toxic for the biological systems. An off-line speciation method using Chelex-100 has been practiced for speciation to Cr(III) and Cr(VI) from surface waters of rivers. The underlying principal of ...