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1.
Int J Biol Macromol ; 149: 127-139, 2020 Apr 15.
Article in English | MEDLINE | ID: mdl-31978476

ABSTRACT

Uranium (U(VI)) is radioactive and the primary raw material in the production of nuclear energy. Hence the research associated with uranium removal gained a lot of importance because to reduce the threat of uranium contamination to ecology and its environment surroundings. Thus, economically as well as environmentally friendly sorbents with a good sorption capacity have to be acquired for the removal of U(VI) pollutants from the aqueous and polluted sea samples. In this study magnetic- Momordica charantia leaf powder impregnated into chitosan (m-MCLPICS) was prepared through the impregnation method. After preparation the adsorbent undergone through various characterizations such as BET, XRD, FTIR, SEM with elemental mapping, and VSM analysis. The specific surface area (93.12 m2/g), pore size (0.212 cm3/g) and pore volume (15.35 nm) of m-MCLPICS was obtained from the BET analysis. A pH value of 5 and 0.5 g of adsorbent dose were selected as an optimum values for U(VI) removal. Kinetic data follows the pseudo-second-order model, and the equilibrium data fitted well with the Langmuir isotherm model. ΔG° (-1.6999, -2.4994, -3.5476 and -4.5147 kJ/mol), ΔH0 (25.1 kJ/mol) and ΔS0 (0.089 kJ/mol K) indicates that the U(VI) sorption process is feasible, spontaneous and endothermic.


Subject(s)
Chitosan/chemistry , Momordica charantia/chemistry , Plant Leaves/chemistry , Uranium/chemistry , Water Pollutants, Radioactive/chemistry , Water Purification , Powders , Wastewater/chemistry
2.
Int J Biol Macromol ; 148: 887-897, 2020 Apr 01.
Article in English | MEDLINE | ID: mdl-31945442

ABSTRACT

In this study m-AHLPICS (magnetic Arachis hypogaea leaves powder impregnated into chitosan) was prepared and utilized as an adsorbent to remove U(VI) from aqueous and real polluted wastewater samples. m-AHLPICS was characterized by using the BET, XRD, FTIR, SEM with elemental mapping and magnetization measurements. Different experimental effects such as pH, dose, contact time, and temperature were considered broadly. Chitosan modified magnetic leaf powder (m-AHLPICS) exhibits an excellent adsorption capacity (232.4 ± 5.59 mg/g) towards U(VI) ions at pH 5. Different kinetic models such as pseudo-first-order, and pseudo-second-order models were used to know the kinetic data. Langmuir, Freundlich and D-R isotherms were implemented to know the adsorption behavior. Isothermal information fitted well with Langmuir isotherm. Kinetic data followed by the pseudo-second-order kinetics (with high R2 values, i.e., 0.9954, 0.9985 and 0.9971) and the thermodynamic data demonstrate that U(VI) removal using m-AHLPICS was feasible, and endothermic in nature.


Subject(s)
Arachis/chemistry , Chitosan/chemistry , Plant Leaves/chemistry , Uranium/chemistry , Water Pollutants, Radioactive/chemistry , Adsorption , Hydrogen-Ion Concentration , Kinetics , Powders , Spectrum Analysis , Temperature , Thermodynamics , Wastewater , Water Pollution , Water Purification
3.
Int J Biol Macromol ; 146: 1100-1110, 2020 Mar 01.
Article in English | MEDLINE | ID: mdl-31682857

ABSTRACT

A novel, eco-friendly aminated chitosan Schiff's base (ACSSB@ZnO) was developed and utilized to remove MO from aqueous environment. The impact of different significant parameters, for example, pH (3-11), adsorbent dose (0.1-0.6 g), contact time (0-120 min), and temperature (303-323 K) have been explored by batch process. Kinetic data was illustrated by pseudo-second-order model and the isotherms fitted well with Langmuir isotherm model. The highest sorption capacity of ACSSB@ZnO was observed to be 111.11 mg/g at 323 K. Positive enthalpy and entropy values demonstrated that the MO adsorption procedure was an endothermic. Negative Gibbs free energy values implied the spontaneous nature of the adsorption system. Moreover, reusability experiments were studied and it can be regenerated by using NaOH as effluent.


Subject(s)
Azo Compounds/isolation & purification , Chitosan/chemical synthesis , Coloring Agents/isolation & purification , Schiff Bases/chemical synthesis , Schiff Bases/pharmacology , Water Pollutants, Chemical/isolation & purification , Adsorption , Amination , Animals , Chitosan/chemistry , Humans , Hydrogen-Ion Concentration , Kinetics , MCF-7 Cells , Male , Mice , Proton Magnetic Resonance Spectroscopy , Schiff Bases/chemistry , Spectroscopy, Fourier Transform Infrared , Surface Properties , Time Factors , X-Ray Diffraction , Zinc Oxide/chemistry
4.
Int J Biol Macromol ; 136: 177-188, 2019 Sep 01.
Article in English | MEDLINE | ID: mdl-31173826

ABSTRACT

It is well-known that heavy metals are non-biodegradable and have been showing remarkable impacts on the environment, public health and economics. Because of high toxic tendency, lead (Pb), is one of the foremost considerable hazardous metal with high environmental impacts. Chitosan is a polysaccharide, and can be utilized in wastewater treatment because of its good sorption ability. Amino and hydroxyl groups (C-3 position) on chitosan can serve as electrostatic interaction and complexation sites for metal cations. Chemical crosslinking can effectively enhance the stability of chitosan in acidic media. Hence a novel, cost-effective and eco-friendly ZnO incorporated into aminated chitosan Schiff's base (ACSSB@ZnO) has been synthesized, characterized (BET, XRD, FTIR, SEM, TEM and 1H NMR), and utilized as an adsorbent for the removal of Pb(II) ions from the aqueous environment. The various operating parameters, such as pH (2-8), agitation speed (30-180), adsorbent dose (0.1-0.8 g), contact time (0-140 min), metal ion concentration and temperature (303-323 K) were investigated. The maximum sorption capacity of Pb(II) onto ACSSB@ZnO was found to be 55.55 mg/g. The equilibrium, and kinetic studies suggested that the adsorption process followed the Langmuir isotherm and Pseudo-Second-Order model. Thermodynamic data showed that the sorption process was feasible, spontaneous, and endothermic.


Subject(s)
Chitosan/chemistry , Lead/chemistry , Lead/isolation & purification , Water Pollutants, Chemical/chemistry , Water Pollutants, Chemical/isolation & purification , Water Purification/methods , Water/chemistry , Adsorption , Hydrogen-Ion Concentration , Kinetics , Schiff Bases/chemistry , Static Electricity , Temperature , Zinc Oxide/chemistry
5.
Ecotoxicol Environ Saf ; 128: 109-17, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26921544

ABSTRACT

Present research discussed the utilization of aminated pumpkin seed powder (APSP) as an adsorbent for methyl orange (MO) removal from aqueous solution. Batch sorption experiments were carried to evaluate the influence of pH, initial dye concentration, contact time, and temperature. The APSP was characterized by using Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). The experimental equilibrium adsorption data were fitted using two two-parameter models (Langmuir and Freundlich) and two three-parameter models (Sips and Toth). Langmuir and Sips isotherms provided the best model for MO adsorption data. The maximum monolayer sorption capacity was found to be 200.3mg/g based on the Langmuir isotherm model. The pseudo-first-order and pseudo-second-order model equations were used to analyze the kinetic data of the adsorption process and the data was fitted well with the pseudo-second-order kinetic model (R(2)>0.97). The calculated thermodynamic parameters such as ΔG(0), ΔH(0) and ΔS(0) from experimental data showed that the sorption of MO onto APSP was feasible, spontaneous and endothermic in the temperature range 298-318 K. The FTIR results revealed that amine and carboxyl functional groups present on the surface of APSP. The SEM results show that APSP has an irregular and porous surface which is adequate morphology for dye adsorption. Desorption experiments were carried to explore the feasibility of adsorbent regeneration and the adsorbed MO from APSP was desorbed using 0.1M NaOH with an efficiency of 93.5%. Findings of the present study indicated that APSP can be successfully used for removal of MO from aqueous solution.


Subject(s)
Azo Compounds/analysis , Cucurbita/chemistry , Ethanolamine/chemistry , Seeds/chemistry , Water Pollutants, Chemical/analysis , Adsorption , Hydrogen-Ion Concentration , Kinetics , Microscopy, Electron, Scanning , Models, Theoretical , Powders , Solutions , Spectroscopy, Fourier Transform Infrared , Surface Properties , Temperature , Thermodynamics
6.
Colloids Surf B Biointerfaces ; 114: 75-81, 2014 Feb 01.
Article in English | MEDLINE | ID: mdl-24176885

ABSTRACT

Solanum melongena leaves are relatively galore and used as inexpensive material. This paper presents the characterization and evaluation of potential of S. melongena leaf powder (SMLP) for removal of Pb(II) from aqueous solution as a function of pH, biomass dosage, initial metal ion concentration, contact time and temperature. Experimental data were analyzed in terms of three kinetic models such as the pseudo-first-order, pseudo-second-order and intraparticle diffusion models and the results showed that the biosorption processes of Pb(II) followed well pseudo-second-order kinetics. Langmuir and Freundlich isotherm models were applied to describe the biosorption process. Langmuir isotherm described the equilibrium data very well, with a maximum monolayer sorption capacity of 71.42 mg/g for Pb(II) ions at 323 K. The biosorption process was spontaneous and endothermic in nature with negative ΔG° (-8.746, -8.509 and -7.983 kJ/mol) and positive value for ΔH° (3.698 kJ/mol).


Subject(s)
Agriculture , Lead/isolation & purification , Plant Leaves/chemistry , Solanum melongena/chemistry , Waste Products , Water Pollutants, Chemical/economics , Water Pollutants, Chemical/isolation & purification , Adsorption , Biodegradation, Environmental , Costs and Cost Analysis , Hydrogen-Ion Concentration , Ion Exchange , Ions , Kinetics , Microscopy, Electron, Scanning , Models, Chemical , Powders , Solutions , Spectrometry, X-Ray Emission , Spectroscopy, Fourier Transform Infrared , Temperature , Time Factors , X-Ray Diffraction
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