Investigation of Kinetic and Isotherm Models for the Removal of Nitrate and Nitrite Ions on MNPs@PIL Adsorbent from Aqueous Solution

2020 ◽  
Vol 94 (13) ◽  
pp. 2829-2835
Author(s):  
Fateme Aflatouni ◽  
Majid Soleimani ◽  
Maryam Dargahi
LWT ◽  
2021 ◽  
pp. 112638
Author(s):  
Samira Raesi ◽  
Reza Mohammadi ◽  
Zahra Khammar ◽  
Giti Paimard ◽  
Sepehr Abdalbeygi ◽  
...  

2013 ◽  
Vol 295-298 ◽  
pp. 1154-1160 ◽  
Author(s):  
Guo Zhi Deng ◽  
Xue Yuan Wang ◽  
Xian Yang Shi ◽  
Qian Qian Hong

The objective of this paper is to investigate the feasibility of phenol adsorption from aqueous solution by Pinus massoniana biochar. Adsorption conditions, including contact time, initial phenol concentration, adsorbent dosage, strength of salt ions and pH, have been investigated by batch experiments. Equilibrium can be reached in 24 h for phenol from 50 to 250 mg• L-1. The optimum pH value for this kind of biochar is 5.0. The amount of phenol adsorbed per unit decreases with the increase in adsorbent dosage. The existence of salt ions makes negligible influence on the equilibrium adsorption capacity. The experimental data is analyzed by the Freundlich and Langmuir isotherm models. Equilibrium data fits well to the Freundlich model. Adsorption kinetics models are deduced and the pseudo-second-order kinetic model provides a good correlation for the adsorbent process. The results show that the Pinus massoniana biochar can be utilized as an effective adsorption material for the removal of phenol from aqueous solution.


2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
H. Nourmoradi ◽  
Mehdi Khiadani ◽  
M. Nikaeen

Multicomponent adsorption of benzene, toluene, ethylbenzene, and xylene (BTEX) was assessed in aqueous solutions by montmorillonite modified with tetradecyl trimethyl ammonium bromide (TTAB-Mt). Batch experiments were conducted to determine the influences of parameters including loading rates of surfactant, contact time, pH, adsorbate concentration, and temperature on the adsorption efficiency. Scanning electron microscope (SEM) and X-ray diffractometer (XRD) were used to determine the adsorbent properties. Results showed that the modification of the adsorbent via the surfactant causes structural changes of the adsorbent. It was found that the optimum adsorption condition achieves with the surfactant loading rate of 200% of the cation exchange capacity (CEC) of the adsorbent for a period of 24 h. The sorption of BTEX by TTAB-Mt was in the order ofB<T<E<X. The experimental data were fitted by many kinetic and isotherm models. The results also showed that the pseudo-second-order kinetic model and Freundlich isotherm model could, respectively, be fitted to the experimental data better than other available kinetic and isotherm models. The thermodynamic study indicated that the sorption of BTEX with TTAB-Mt was achieved spontaneously and the adsorption process was endothermic as well as physical in nature. The regeneration results of the adsorbent also showed that the adsorption capacity of adsorbent after one use was 51% to 70% of original TTAB-Mt.


2017 ◽  
Vol 75 (9) ◽  
pp. 2034-2046 ◽  
Author(s):  
Adnan Khan ◽  
Samina Begum ◽  
Nauman Ali ◽  
Sabir Khan ◽  
Sajjad Hussain ◽  
...  

A chitosan magnetic membrane was prepared in order to confer magnetic properties to the membrane, which could be used for the removal of cations from aqueous solution. The crosslinked magnetic membrane was compared with pristine chitosan membrane in term of stability, morphology and cation adsorption capacity. The fabricated magnetic materials are thermally stable as shown by thermogravimetric curves. The membrane containing nickel magnetic particles (CHNiF-G) shows high thermal stability compared to the other membranes. The Fourier transform infrared spectroscopy showed successful preparation of chitosan magnetic membrane. Scanning electron microscopy micrographs showed the rough surface of the membrane with increased porosity. The prepared chitosan membranes were applied to cations of copper, nickel and lead in dilute aqueous solution. The chitosan membrane showed the following adsorption order for metallic cations: Cu2+ &gt; Ni2+ &gt; Pb2+, while CHNiF-G showed higher capacity, 3.51 mmol g−1 for copper, reflecting the improvement in adsorption capacity, since the amount of copper on pristine chitosan gave 1.40 mmol g−1. The time required for adsorption to reach to the equilibrium was 6 h for the selected cations using different chitosan membranes. The kinetic study showed that adsorption followed pseudo-second order kinetics. The most commonly used isotherm models, Freundlich, Langmuir and Temkin, were applied to experimental data using linear regression technique. However, The Temkin model fits better to experimental data.


2017 ◽  
Vol 76 (7) ◽  
pp. 1726-1738 ◽  
Author(s):  
Raluca Maria Hlihor ◽  
Mihaela Roşca ◽  
Teresa Tavares ◽  
Maria Gavrilescu

The aim of this paper was to establish the optimum parameters for the biosorption of Pb(II) by dead and living Arthrobacter viscosus biomass from aqueous solution. It was found that at an initial pH of 4 and 26 °C, the dead biomass was able to remove 97% of 100 mg/L Pb(II), while the living biomass removed 96% of 100 mg/L Pb(II) at an initial pH of 6 and 28 ± 2 °C. The results were modeled using various kinetic and isotherm models so as to find out the mechanism of Pb(II) removal by A. viscosus. The modeling results indicated that Pb(II) biosorption by A. viscosus was based on a chemical reaction and that sorption occurred at the functional groups on the surface of the biomass. Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy coupled with energy dispersive X-ray microanalysis (SEM-EDX) analyses confirmed these findings. The suitability of living biomass as biosorbent in the form of a biofilm immobilized on star-shaped polyethylene supports was also demonstrated. The results suggest that the use of dead and living A. viscosus for the removal of Pb(II) from aqueous solutions is an effective alternative, considering that up to now it has only been used in the form of biofilms supported on different zeolites.


2019 ◽  
Vol 2 (04) ◽  
pp. 15-26
Author(s):  
Beniah Obinna Isiuku ◽  
Francis Chizoruo Ibe

The biosorption of metanil yellow on hen egg membrane from aqueous solution in a batch process was investigated at 29oC with a view to determine the potential of the membrane in removing metanil yellow from aqueous solution.  The effects of contact time, initial biosorbate concentration, biosorbent dosage and initial biosorbate pH were determined. Various isotherm models were used to analyze experimental data. The highest experimental equilibrium biosorption capacity obtained was 129.88 mg/g. The optimum pH was 3. Adsorption capacity increased with increase in initial solution concentration but decreased with increase in time. The isotherm models applied were good fits based on correlation coefficients. Flory-Huggins isotherm was the best fit (R2 0.986). The biosorption was endothermic, good, physisorptive and spontaneous. This work shows that hen egg membrane is a potential biosorbent for the removal of metanil yellow from aqueous solution.


2017 ◽  
Vol 13 (27) ◽  
pp. 425
Author(s):  
Azeh Yakubu ◽  
Gabriel Ademola Olatunji ◽  
Folahan Amoo Adekola

This investigation was conducted to evaluate the adsorption capacity of nanoparticles of cellulose origin. Nanoparticles were synthesized by acid hydrolysis of microcrystalline cellulose/cellulose acetate using 64% H3PO4 and characterized using FTIR, XRD, TGA-DTGA, BET and SEM analysis. Adsorption kinetics of Pb (II) ions in aqueous solution was investigated and the effect of initial concentration, pH, time, adsorbent dosage and solution temperature. The results showed that adsorption increased with increasing concentration with removal efficiencies of 60% and 92.99% for Azeh2 and Azeh10 respectively for initial lead concentration of 3 mg/g. The effects of contact time showed that adsorption maximum was attained within 24h of contact time. The maximum adsorption capacity and removal efficiency were achieved at pH6. Small dose of adsorbent had better performance. The kinetics of adsorption was best described by the pseudo-second-Order model while the adsorption mechanism was chemisorption and pore diffusion based on intra-particle diffusion model. The isotherm model was Freundlich. Though, all tested isotherm models relatively showed good correlation coefficients ranging from 0.969-1.000. The adsorption process was exothermic for Azeh-TDI, with a negative value of -12.812 X 103 KJ/mol. This indicates that the adsorption process for Pb by Azeh-TDI was spontaneous. Adsorption by Azeh2 was endothermic in nature.


2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Dhiraj Dutta ◽  
Jyoti Prasad Borah ◽  
Amrit Puzari

Results of investigation on adsorption of Mn2+ from aqueous solution by manganese oxide-coated hollow polymethylmethacrylate microspheres (MHPM) are reported here. This is the first report on Mn-coated hollow polymer as a substitute for widely used materials like green sand or MN-coated sand. Hollow polymethylmethacrylate (HPM) was prepared by using a literature procedure. Manganese oxide (MnO) was coated on the surface of HPM (MHPM) by using the electroless plating technique. The HPM and MHPM were characterized by using optical microscopy (OM), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). Optical and scanning micrographs were used to monitor the surface properties of the coated layer which revealed the presence of MnO on the surface of HPM. TGA showed the presence of 4-5% of MnO in MHPM. Adsorption isotherm studies were carried out as a function of pH, initial ion concentration, and contact time, to determine the adsorption efficiency for removal of Mn2+ from contaminated water by the synthesized MHPM. The isotherm results showed that the maximum adsorption capacity of MnO-coated HPM to remove manganese contaminants from water is 8.373 mg/g. The obtained R 2 values of Langmuir isotherm and Freundlich isotherm models were 1 and 0.87, respectively. Therefore, R 2 magnitude confirmed that the Langmuir model is best suited for Mn2+ adsorption by a monolayer of MHPM adsorbent. The material developed shows higher adsorption capacity even at a higher concentration of solute ions, which is not usually observed with similar materials of this kind. Overall findings indicate that MHPM is a very potential lightweight adsorbent for removal of Mn2+ from the aqueous solution because of its low density and high surface area.


Author(s):  
F. U. Okwunodulu ◽  
H. O. Chukwuemeka-Okorie ◽  
N. M. Mgbemena ◽  
J. B. I. Kalu

The removal of Cr6+ from aqueous solution using unmodified and hydrochloric modified African nutmeg pod was studied. The effects of particle size, pH and initial metal ions concentration adsorbed were investigated. The amount of metal ion adsorbed increased as the initial metal ion concentration increased and also decreased at low pH of 2 for both modified and unmodified African nutmeg pod.  400 µm and 250 µm were the optimum particle sizes for both modified and unmodified African nutmeg pod respectively, values given as 75.8 mg/g for the modified and 93.39 mg/g for the unmodified. Generally, it was observed that the unmodified African nutmeg pod showed greater adsorption capacity than the modified African nutmeg pod. The equilibrium experimental data were examined via Langmuir and Freundlich isotherm models.  Freundlich isotherm model gave the best fit for the data in both unmodified and modified African nutmeg pod based on the correlation coefficients (R2 values) gotten. The results of the study showed that the African nutmeg pod is efficient for the removal of Cr6+ from aqueous solutions especially when unmodified.


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