BACKGROUND Kinetics, thermodynamics and equilibrium of the removal of chromium(VI) ions from aqueous solutions by using chemically activated leaves of Ficus nitida were investigated. Adsorption runs were performed as a function of pH, mass of biosorbent, contact time, initial concentration of chromium(VI) ions and temperature. RESULTS The optimum conditions for maximum removal of chromium(VI)...

In this work, waste marigold flowers from Temple were used as adsorbent to remove cadmium (II) and chromium (VI) ions from aqueous solutions. Influences of initial heavy metal concentrations, contact time, adsorbent dose, temperature and initial pH on removal of cadmium (II) and chromium (VI) ions were studied under batch mode of operation. Both the adsorption process of cadmium (II) and chromi...

chromium is one of the major causes of environmental pollution. to remove heavy metal ions from water, microorganisms can be used. in this study, dead fungal biomass of aspergillus niger is used. the biomass was boiled in 0.5 n naoh solutions to increase the metal removal capacity of a.niger and was applied when the ph of wash solution was in the normal range. the optimum adsorption ph value ob...

BACKGROUND In this study the removal of Chromium (III) and Chromium (VI) ions are investigated via polymer enhanced ultrafiltration under important process parameters. This study proposes the use of unmodified starch as a novel polymer in the ultrafiltration process and its performance on the removal of chromium ions was compared with a commonly used polymer, polyethylene glycol. METHODS The ...

the potential of citrobacter freundii, a gram negative bacteria for the remediation of hexavalentchromium (cr(vi)) and trivalent chromium (cr(iii)) from aqueous solutions was investigated. bioremediationof cr(vi) involved both biosorption and bioreduction processes, as compared to only biosorption processobserved with respect to cr(iii) bioremediation. in the case of cr(vi) bioremediation studi...

Industrial wastewater contain higher quantities of salts besides chromium (VI) ions, therefore, the effect of these salts on the adsorption of chromium (VI) should be studied. In this research, the batch removal of toxic hexavalent chromium ions from wastewater and aqueous solution using two different activated carbon marine algae Gracilaria (red algae) and Sargassum sp. (brown algae) were exam...

rice husk is as an organic solid waste material that has high adsorbing capacity in removal of heavy metal ions from wastewater, and can be very effective in treating industrial aqueous solutions that are important sources of water and soil pollution. in this study, the removal of zn(ii) and cr(vi) ions from aqueous solutions using rice husk was investigated. the investigated parameters include...

BACKGROUND Chromium (VI) has toxic and carcinogenic effects. So, determination and speciation of chromium in environmental samples is very important in view of health hazards. In this study, solid phase extraction (SPE) based on bulky amine-functionalized bimodal mesoporous silica nanoparticles (NH2-UVM-7) as a novel nanoadsorbent was applied for preconcentration and speciation of chromium (III...

In this study, removal of chromium(VI) from aqueous solutions by Palmyra palm fruit seed carbon (PPFSC) and commercial activated carbon (CAC) was investigated. The metal adsorption capacity has been studied as a function of contact time, pH and carbon dosage. The adsorption yields increased with the increasing of adsorbent dosage and contact time, and subsequently reached the equilibrium. The s...

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 ...