Adsorption of basic dye on high-surface-area activated carbon prepared from coconut husk: equilibrium, kinetic and thermodynamic studies.

Waste materials for activated carbon preparation and its use in aqueous-phase treatment: a review.

Adsorption isotherms, kinetics, thermodynamics and desorption studies of 2,4,6-trichlorophenol on oil palm empty fruit bunch-based activated carbon.

Adsorption isotherm, kinetic modeling and mechanism of 2,4,6-trichlorophenol on coconut husk-based activated carbon

Removal of lead (II) and copper (II) from aqueous solution using pomegranate peel as a new adsorbent

BACKGROUND: The removal of heavy metals using adsorption techniques with low cost biosorbents is being extensively investigated. The improved adsorption is essentially due to the pores present in the adsorbent. One way of improving the porosity of the material is by irradiation of the precursor using microwaves. In the present study, the adsorption characteristics of nickel onto microwave-irradiated rice husks were studied and the process variables were optimized through response surface methodology (RSM).



RESULT: The adsorption of nickel onto microwave-irradiated rice husk (MIRH) was found to be better than that of the raw rice husk (RRH). The kinetics of the adsorption of Ni(II) from aqueous solution onto MIRH was found to follow a pseudo-second-order model. Thermodynamic parameters such as standard Gibbs free energy (ΔG°), standard enthalpy (ΔH°), and standard entropy (ΔS°) were also evaluated. The thermodynamics of Ni(II) adsorption onto MIRH indicates that it is spontaneous and endothermic in nature. The response surface methodology (RSM) was employed to optimize the design parameters for the present process.



CONCLUSION: Microwave-irradiated rice husk was found to be a suitable adsorbent for the removal of nickel(II) ions from aqueous solutions. The adsorption capacity of the rice husk was found to be 1.17 mg g−1. The optimized parameters for the current process were found as follows: adsorbent loading 2.8 g (100 mL)−1; Initial adsorbate concentration 6 mg L−1; adsorption time 210 min.; and adsorption temperature 35 °C. Copyright © 2008 Society of Chemical Industry

Optimization and analysis of nickel adsorption on microwave irradiated rice husk using response surface methodology (RSM)

The defilement of water bodies is going on increasing due to the use of noxious chemicals. In the present study, to alleviate the deadly effects of the heavy metal, the agricultural solid waste Citrullus lanatus rind was used as the precursor for the Nickel ion removal. To remove Nickel from synthetic solution, adsorption studies were conducted. Characterization was done using TGA, SEM and FT‐IR analysis. Various parameters on the adsorption capacity of the adsorbent, isotherm and kinetic studies were carried out. The maximum loading capacity of Ni²⁺ was found to be 38.98 mg/g from Langmuir model. Error analyses were also studied to validate the best fit of the curve for isotherm models. The kinetic models were studied to understand the adsorption mechanism. The dynamic behaviour of the fixed column and the modelling of the breakthrough curves were carried out. Desorption studies were performed to consider the reusability of the rind.

Study of mathematical models for the removal of Ni2+ from aqueous solutions using Citrullus lanatus rind, an agro‐based waste

Ultrafiltration Polyetherimide (PEI) polymeric membrane was modified by the incorporation of graphene oxide (GO) (0.2, 0.6 and 1 wt %) and PluronicF-127 (PF127) (1 wt %) using the phase inversion technique for synthetically produced oil-water separation. GO nanoparticles were prepared by the Hummers method and it was analyzed by FTIR, XRD, Raman, and TGA. ATR-FTIR is attributed to measure the functional groups in the prepared membrane. The effect of GO and PF127 loading on the prepared membranes was evaluated by SEM, AFM, viscosity, water uptake capacity, surface porosity, tortuosity, and pore radius. The contact angle measurements are performed to determine the hydrophilicity of the prepared membranes. The thermal and mechanical stability of prepared membranes is determined by TGA and mechanical test analyzer. The performances of prepared membranes were determined by permeability, rejection, and antifouling properties using crude oil as a feed solution. In the filtration performances, the membrane synthesized with composition PEI (17 wt %), PF127 (1 wt %) and GO (0.6 wt %) showed better rejection of 95% which ameliorates the flux of 266.5 L m−2 h−1 and also it bolster the flux recovery ratio of 93% with improved recyclability performance. The improved results were obtained by the modification of the PEI membrane matrix with the addition of highly hydrophilic synthesized GO nanoparticles, that produced an enhanced efficiency in the separation of oil wastewater.

M. Helen Kalavathy

Papers

Optimization and analysis of nickel adsorption on microwave irradiated rice husk using response surface methodology (RSM)

Study of mathematical models for the removal of Ni2+ from aqueous solutions using Citrullus lanatus rind, an agro‐based waste

Performance studies of GO/PF127 incorporated Polyetherimide Ultrafiltration membranes for the rejection of oil from oil wastewater

Development of carbon-based material from biomass for the removal of Ni2+ and CO2 from fluid phase

Pore Formation Mechanism and Sorption Studies Using Activated Carbon from Gleditsia Triacanthos