Removal and recovery of Ni(II) ions from synthetic wastewater using surface modifiedStrychnos potatorumseeds: experimental optimization and mechanism

Abstract

2015) Removal and recovery of Ni(II) ions from synthetic wastewater using surface modified Strychnos potatorum seeds: experimental optimization and mechanism, Desalination and Water Treatment, 53:1, 171-182, A B S T R A C TStrychnos potatorum seeds have been utilized for the preparation of adsorbent, surface modified S. potatorum seeds (SMSP), by sulfuric acid treatment with 1:2 ratios of precursor to sulfuric acid. The adsorption process depends on the solution pH, adsorbent dose, contact time, initial Ni(II) ions concentration, and temperature. The adsorption kinetics of Ni(II) ions removal by the SMSP was relatively fast and it reaches the equilibrium at 30 min. The maximum removal of Ni(II) ions was observed at an optimum conditions: pH of 5.0, adsorbent dose of 5 g/L, contact time of 30 min, and at temperature of 30˚C for an initial Ni(II) ions concentration of 100 mg/L. In order to investigate the adsorption kinetics for the removal of Ni(II) ions by SMSP, pseudo-first-order and pseudo-secondorder kinetic models were studied. It was observed that the pseudo-second-order kinetic model fits the experimental data better than the pseudo-first-order kinetic model with good coefficient of determination values. Adsorption mechanism was discussed with different models such as intraparticle diffusion, Boyd kinetic, and shrinking core models. It was observed that the adsorption process was controlled by both film and particle diffusion. The effective diffusivity and diffusivity values were estimated from the Boyd kinetic and shrinking core models, respectively. Adsorption isotherm data were tested with the Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich models. It was observed that the Freundlich model fits the isotherm data better than other isotherm models with good coefficient of determination values. The Freundlich constant "n" was found to be of 3.888 g/L which indicates that the adsorption of Ni(II) ions onto the SMSP followed the physical process. The thermodynamic parameters such as change in free energy, enthalpy, and entropy were also calculated. It was found that the adsorption process was spontaneous and exothermic in nature.

Adsorption of hexavalent chromium onto alkali‐modified biochar derived from Lepironia articulata: A kinetic, equilibrium, and thermodynamic study

“…Chromium(VI) is a nonbiodegradable and toxic heavy metal, which in water often takes both cation and anion forms (Mahmoud & Lazaridis, ). This heavy metal is usually discharged in various industrial effluents from leather tanning, pigments, steel fabrication, textile dyeing, paint manufacturing, electroplating, battery manufacturing, automotive and agriculture, and steam electric power plants (Anbalagan et al, ; Ferraz, Tavares, & Teixeira, ; Mahmoud & Lazaridis, ) . Major health problems caused by chromium include lung cancer, weakened immune system respiratory problems, kidney and liver damage, skin rashes, and death.…”

Optimization of process parameters for the removal of chromium(VI) and nickel(II) from aqueous solutions by mixed biosorbents (custard apple seeds andAspergillus niger) using response surface methodology

“…Fig. 3 shows the % removal of chromium(VI) ions over a range of pH (2)(3)(4)(5)(6) at the temperature of 36˚C and at the biosorbent loading of 15 g/L. The maximum removal of chromium(VI) ions onto the mixed biosorbents was observed at the pH of 3.0.…”

“…(2015) [1][2][3][4][5][6][7][8][9][10][11][12][13][14] www.deswater.com doi: 10.1080/19443994.2015.1064034 human beings due to its mutagenic and carcinogenic properties [1,2]. Chromium(VI) and nickel(II) ions are the nonbiodegradable toxic heavy metals which often exist in the water habitats from industrial effluents such as textile dyeing, pigments, electroplating, leather tanning, metal mining, paint manufacturing, steel fabrication, battery manufacturing, automotive, steam electric power plants, and agricultural wastes [3,4].…”

“…Chromium(VI) and nickel(II) ions are the nonbiodegradable toxic heavy metals which often exist in the water habitats from industrial effluents such as textile dyeing, pigments, electroplating, leather tanning, metal mining, paint manufacturing, steel fabrication, battery manufacturing, automotive, steam electric power plants, and agricultural wastes [3,4]. Inhaling chromium(VI) can cause nose irritations and nosebleeds.…”

Adsorption kinetic, equilibrium and thermodynamic investigations of Zn(II) and Ni(II) ions removal by poly(azomethinethioamide) resin with pendent chlorobenzylidine ring

“…Adsorption remains to be the most popular technique due to its fl exibility and simple in design, convenience and ease of operation and higher effi ciency in removing heavy metal ions especially at lower concentration. Various adsorbents were employed for the removal of metal ions from the aqueous solutions which includes surface modifi ed Strychnos potatorum seeds 2, 13 , bael tree leaves 8- 9 , cashew nut shell 10-11 , unmodifi ed [4]arene 26 and etc. The objective of the present research is to develop an effective polymeric material with maximum adsorption capacity for the removal of Zn(II) and Ni(II) ions from the aqueous solution.…”