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This study provides an electrocoagulation process for the removal of metals such as cobalt, copper, and chromium from water using magnesium as anode and galvanized iron as cathode. The various parameters like pH, current density, temperature, and inter electrode distance on the removal efficiency of metals were studied. The results showed that maximum removal efficiency was achieved for cobalt, copper, and chromium with magnesium as anode and galvanized iron as cathode at a current density of 0.025?A?dm?2 at pH 7.0. First- and second-order rate equations were applied to study adsorption kinetics. The adsorption process follows second-order kinetics model with good correlation. The Langmuir and Freundlich adsorption isotherm models were studied using the experimental data. The Langmuir adsorption isotherm favors monolayer coverage of adsorbed molecules for the adsorption of cobalt, copper, and chromium. Temperature studies showed that adsorption was endothermic and spontaneous in nature. 相似文献
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K.D.P. Nigam R.K. Srivastav S.K. Gupta P. Vasudevan 《Environmental Modeling and Assessment》1998,3(4):249-258
A mathematical model is developed for metal ions uptake by aquatic plants. The model is based on a mechanism which assumes
that the complex biological substances present in the plant react with the metal ions to form complexes of these ions at the
solution–plant interface, and then the metal complexes diffuse through a membrane towards the bulk phase of the plant because
of the concentration gradients present in the membrane. The model predicts the decreasing capacity of the plants for metal
ions uptake as the contact time between the solution and the plant is increased. Experiments are conducted in the laboratory
for the removal of chromium, copper, iron, nickel, lead and zinc by measuring metal ions uptake by two aquatic plants, Salvinia
and Spirodela, in the solution of these metal ions of concentration ranging from 1 to 8 ppm. After estimating the parameters
of the model, it is used for predicting the metal ions concentration in the solution as a function of time and the metal ions
concentration inside the plants after 14 days of contact time. The comparison of the model predictions with the experimental
results shows excellent agreement. The above model may be used for design and analysis of an aquatic‐plant‐based waste water
treatment system.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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Berlin Mohanadhas Natarajan Narayanan Vasudevan Mangottiri Suresh Kumar Govindarajan 《Environmental science and pollution research international》2021,28(15):18632-18650
Environmental Science and Pollution Research - The subsurface leaching of soluble chemicals in a fractured porous medium poses long-term risk of groundwater contamination. Tracing the occurrence,... 相似文献
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A halotolerant bacterial strain VA1 isolated from marine environment was studied for its ability to utilize polycylic aromatic
hydrocarbons (PAHs) under saline condition. Anthracene and pyrene were used as representatives for the utilization of PAH by the
bacterial strain. Glucose and sodium citrate were used as additional carbon sources to enhance the PAH utilization. The strain VA1
was able to utilize anthracene (73%) and pyrene (66%) without any additional substrate. In the presence of additional carbon sources
(glucose/sodium citrate) the utilization of PAH was faster. PAH was utilized faster by VA1 in the presence of glucose than sodium citrate.
The stain utilized 87% and 83% of anthracene and pyrene with glucose as carbon source and with sodium citrate the strain utilized 81%
and 76% respectively in 4 days. Urea as an alternative source of nitrogen also enhanced the utilization of PAHs (anthracene and pyrene)
by the bacterial strain up to 88% and 84% in 4 days. Sodium nitrate as nitrogen source was not able to enhance the PAH utilization rate.
Phenotypic and phlyogenetic analysis proved that the PAHs utilizing halotolerant strain VA1 belongs to Ochrobactrum sp. 相似文献