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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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Shubha Nigam Padma S. Vankar Krishna Gopal 《Environmental science and pollution research international》2013,20(2):1161-1172
The purpose of this study is to examine on removal of arsenic from water by biosorption through potential application of herbal dye wastes. Four different flower dye residues (after extraction of natural dye) viz. Hibiscus rosasinensis, Rosa rosa, Tagetes erecta, and Canna indica were utilized successfully for the removal of arsenic from aqueous solution. Batch studies were carried out for various parameters viz. pH, sorbent dose, contact time, initial metal ion concentration, and temperature. Data were utilized for isothermal, kinetic, and thermodynamic studies. Scanning electron microscopy (SEM), energy-dispersive x-ray spectroscopy (EDAX), and Fourier transform infrared (FTIR) analyses of biomass were performed. The results showed that 1 g/100 ml for 5.0–5.5 h contact time at pH 6.0–7.5 with agitation rate 150 rpm provided 98, 96, 92, and 85 % maximum absorption of arsenic by R. rosa, H. rosasinensis, T. erecta, and C. indica, respectively, at initial concentration of 500 ppb. Data followed Langmuir isotherm showing sorption to be monolayer on heterogeneous surface of biosorbent. Negative values of ΔG° indicated spontaneous nature, whereas ΔH° indicates exothermic nature of system followed by pseudo-first-order adsorption kinetics. FTIR results showed apparent changes in functional group regions after metal chelation. SEM and EDAX analyses showed the changes in surface morphology of all test biosorbents. Herbal dye wastes, used as biosorbent, exhibited significant (85–98 %) removal of arsenic from aqueous solution. Hence, these biosorbents are cost-effective, easily available, eco-friendly, and comparatively more effective than other biosorbents already in use. These may be used to remove arsenic and other toxic metals from water. 相似文献
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Nigam Sonal Singh Rachana Bhardwaj Sheetal Kaushik Sami Rokkayya Nikolova Maria P. Chavali Murthy Sinha Surbhi 《Journal of Polymers and the Environment》2022,30(3):785-809
Journal of Polymers and the Environment - Algae are an enormous source of polysaccharides and have gained much interest in human flourishing as organic drugs. Algal polysaccharides have aroused... 相似文献