Kinetic evaluation of chromium(VI) sorption by water lettuce (Pistia)

2013 ◽  
Vol 69 (1) ◽  
pp. 195-201 ◽  
Author(s):  
Rupa Chakraborty ◽  
Sukalpa Karmakar ◽  
Somnath Mukherjee ◽  
Sunil Kumar
Keyword(s):  
Plant Root ◽  
Freundlich Isotherm ◽  
Living Condition ◽  
Isotherm Models ◽  
Contact Period ◽  
Uptake Capacity ◽  
Kinetic Evaluation ◽  
Initial Concentration ◽  
Chromium Vi ◽  
Equilibrium Level

An investigation was performed to evaluate the uptake capacity of Pistia in living condition for adsorptive removal of chromium(VI) from spiked solution for examining a remedial measure for disposal of chrome-laden wastewater in an urban wetland system. Kinetics results show about 78% removal was achieved for 3 mg/L initial concentration of Cr(VI). Experimental data showed that the root portion absorbed more Cr(VI) (28.54 μg/g) compared to accumulation in leaf (5.73 μg/g). It was also noted that the plant could effectively remove Cr(VI) from the solution with minor damage up to an initial Cr(VI) concentration of 3 mg/L, for which the adsorption isotherm studies were conducted. The maximum uptake capacity of the plant was recorded as 0.05 mg/g of Cr(VI) at the equilibrium level after a contact period of 7 days for an initial concentration of 8 mg /L, although severe physiological damage occurred. The experimental results were plotted in Langmuir and Freundlich isotherm models and both were found to be well fitted (r2 = 0.979 and r2 = 0.974 respectively). The high value of n (2.16) reveals a strong bond between the plant root and dissolved Cr(VI), which favours the adsorption process. The order of the reaction was also examined on the basis of uptake capacity and it was found that the second order model fitted best.

Nanoparticle Fe3O4 magnetized activated carbon from Armeniaca sibirica shell for the adsorption of Hg(II) ions

BioResources ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. 6100-6120
Author(s):  
Yinan Hao ◽  
Yanfei Pan ◽  
Qingwei Du ◽  
Xudong Li ◽  
Ximing Wang
Keyword(s):  
Activated Carbon ◽  
Adsorption Capacity ◽  
Ph Value ◽  
Removal Rate ◽  
Freundlich Isotherm ◽  
Entropy Change ◽  
Isotherm Models ◽  
Order Kinetic ◽  
Adsorption Parameters ◽  
Initial Concentration

Armeniaca sibirica shell activated carbon (ASSAC) magnetized by nanoparticle Fe3O4 prepared from Armeniaca sibirica shell was investigated to determine its adsorption for Hg2+ from wastewater. Fe3O4/ASSAC was characterized using XRD (X-ray diffraction), FTIR (Fourier transform infrared spectroscopy), SEM (scanning electron microscopy), and BET (Brunauer–Emmett–Teller). Optimum adsorption parameters were determined based on the initial concentration of Hg2+, reaction time, reaction temperature, and pH value in adsorption studies. The experiment results demonstrated that the specific surface area of ASSAC decreased after magnetization; however the adsorption capacity and removal rate of Hg2+ increased 0.656 mg/g and 0.630%, respectively. When the initial concentration of Hg2+ solution was 250 mg/L and the pH value was 2, the adsorption time was 180 min and the temperature was 30 °C, and with the Fe3O4/ASSAC at 0.05 g, the adsorption reaching 97.1 mg/g, and the removal efficiency was 99.6%. The adsorption capacity of Fe3O4/ASSAC to Hg2+ was in accord with Freundlich isotherm models, and a pseudo-second-order kinetic equation was used to fit the adsorption best. The Gibbs free energy ΔGo < 0，enthalpy change ΔHo < 0, and entropy change ΔSo < 0 which manifested the adsorption was a spontaneous and exothermic process.

scholarly journals Utilization of Activated Carbon Prepared from Industrial Solid Waste for the Removal of Chromium(VI) Ions from Synthetic Solution and Industrial Effluent

2005 ◽  
Vol 23 (2) ◽  
pp. 145-160 ◽  
Author(s):  
N. Vennilamani ◽  
K. Kadirvelu ◽  
Y. Sameena ◽  
S. Pattabhi
Keyword(s):  
Activated Carbon ◽  
Metal Ion ◽  
Industrial Effluent ◽  
Carbon Adsorbent ◽  
Freundlich Isotherm ◽  
Ion Concentration ◽  
Isotherm Models ◽  
Adsorption Sites ◽  
Chromium Vi ◽  
Sago Waste

Activated carbon (AC) prepared from sago waste was characterized and used to remove chromium(VI) ions from aqueous solution and industrial effluent by adsorption methods using various conditions of agitation time, metal ion concentration, adsorbent dosage particle size and pH. Surface modification of the carbon adsorbent with a strong oxidizing agent like concentrated H2SO4 generates more active adsorption sites on the solid surface and pores for metal ion adsorption. Adsorption of the metal ion required a very short time and led to quantitative removal. Both the Langmuir and Freundlich isotherm models could describe the adsorption data. The calculated values of Q0 and b were 5.78 mg/g and 1.75 1/min, respectively. An effective adsorption capacity was noted for particle sizes in the range 125–250 μm at room temperature (30 ± 2°C) and an initial pH of 2.0 ± 0.2. The specific surface area of the activated carbon was determined and its properties studied by scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FT-IR). These studies revealed that AC prepared from sago waste is suitable for the removal of Cr(VI) ions from both synthetic and industrial effluents.

scholarly journals Magnetite Functionalized Nigella Sativa Seeds for the Uptake of Chromium(VI) and Lead(II) Ions from Synthetic Wastewater

2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Patience Mapule Thabede ◽  
Ntaote David Shooto ◽  
Thokozani Xaba ◽  
Eliazer Bobby Naidoo
Keyword(s):  
Nigella Sativa ◽  
Freundlich Isotherm ◽  
Synthetic Wastewater ◽  
Batch Adsorption ◽  
Initial Concentration ◽  
X Ray ◽  
Operational Conditions ◽  
First Order ◽  
Chromium Vi ◽  
Ketonic Group

The aim of the present study was to utilise pristine and magnetite-sucrose functionalized Nigella Sativa seeds as the adsorbents for the uptake of chromium(VI) and lead(II) ions from synthetic wastewater. Prestine Nigella Sativa seeds were labelled (PNS) and magnetite-sucrose functionalized Nigella Sativa seeds (FNS). The PNS and FNS composites were characterized by Fourier-transform infrared spectroscopy (FTIR) and X-ray powder diffraction (XRD). The FTIR analysis of both adsorbents revealed the presence of vibrations assigned to 1749 and 1739 cm-1 (-C=O) for ketonic group for both adsorbents. The amide (-NH) peak was observed at 1533 and 1527 cm-1 on FNS and PNS composites, respectively, whilst the carboxyl group (-COOH) were observed at 1408 cm-1 on both adsorbents. The XRD results of FNS and PNS composites showed a combination of spinel structure and y -Fe2O3 phase confirming the formation of iron oxide. The influence of operational conditions such as initial concentration, temperature, pH, and contact time was determined in batch adsorption system. The kinetic data of Cr(VI) and Pb(II) ions on both adsorbents was described by pseudo-first-order (PFO) model which suggested physisorption process. The sorption rate of Cr(VI) ions was quicker, it attained equilibrium in 20 min, and the rate of Pb(II) ions was slow in 90 min. Freundlich isotherm described the mechanism of Pb(II) ions adsorption on PNS and FNS composites. Langmuir best fitted the uptake of Cr(VI) ions on PNS and FNS. The results for both adsorbents showed that the removal uptake of Pb(II) ions increased when the initial concentration was increased; however, Cr(VI) uptake decreased when the initial concentration increased. The adsorption of Cr(VI) and Pb(II) ions on both adsorbents increased with temperature.

scholarly journals ADSORPTION OF FLUORIDE USING SIO2 NANOPARTICLES AS ADSORBENT

2020 ◽  
Vol 2 (2) ◽  
pp. 1-9
Author(s):  
Davoud Balarak ◽  
Yousef Mahdavi ◽  
Ali Joghatayi
Keyword(s):  
Aqueous Solution ◽  
Contact Time ◽  
Low Cost ◽  
Freundlich Isotherm ◽  
Sio2 Nanoparticles ◽  
Second Order ◽  
Isotherm Models ◽  
Maximum Adsorption Capacity ◽  
Initial Concentration ◽  
High Doses

Presence of Fluoride in water is safe and effective when used as directed, but it can be harmful at high doses. In the present paper SiO2 nanoparticles as a adsorbent is used for removal of fluoride from aqueous solution. The effect of various operating parameters such as initial concentration of F-, Contact time, adsorbent dosage and pH were investigated. Equilibrium isotherms were used to identify the possible mechanism of the adsorption process. Maximum adsorption capacity of the SiO2 nanoparticles was 49.95 mg/g at PH=6, contact time 20 min, initial concentration of 25 mg/L, and 25±2 ◦C temperatures, when 99.4% of Fwere removed. The adsorption equilibriums were analyzed by Langmuir and Freundlich isotherm models. It was found that the data fitted to Langmuir (R2=0.992) better than Freundlich (R2=0.943) model. Kinetic analyses were conducted using pseudo first-and second-order models. The regression results showed that the adsorption kinetics was more accurately represented by a pseudo second-order model. These results indicate that SiO2 nanoparticles can be used as an effective, low-cost adsorbent to remove fluoride from aqueous solution.

scholarly journals Removal of Pb(II) from Aqueous Solution by Ceramsite Prepared from Isfahan Bentonite and γ-Alumina

2021 ◽  
Vol 15 (2) ◽  
pp. 263-273
Author(s):  
Iman Mobasherpour ◽  
◽  
Masomeh Javaherai ◽  
Esmail Salahi ◽  
Mohsen Ebrahimi ◽  
...  
Keyword(s):  
Adsorption Capacity ◽  
Freundlich Isotherm ◽  
Isotherm Models ◽  
The Novel ◽  
Absorption Process ◽  
Initial Concentration ◽  
Adsorbent Dosage ◽  
Adsorption Data ◽  
Ft Ir ◽  
Central Composite

Removal of lead from aqueous solutions was studied using nanocomposite absorbent of bentonite/-alumina. The novel absorbent was characterized using XRD, FT-IR and SEM-EDX. Absorption process optimization using response surface methodology (RSM) and experimental design was performed with central composite design technique. The effects of Pb(II) initial concentration, adsorbent dosage, and composite percentage on Pb(II) removal percentage and adsorption capacity were examined. The adsorption capacity of 166.559 mg/g and removal % of 82.9887 with desirability equal to 0.763 were obtained for optimal initial concentration of 200 mg•l-1, adsorbent dosage of 0.5 mg•l-1, and composite percentage of 7.08 % determined using RSM design. The equilibrium adsorption data were investigated by Langmuir, Freundlich and Dubinin-Radushkevich isotherm models. It was found that Freundlich isotherm model fits better compared with other models.

scholarly journals Biosorption of Copper (II) from Aqueous Solution using a Combination of Orange Peels and Tea Waste

2021 ◽  
Vol 920 (1) ◽  
pp. 012039
Author(s):  
N N Noordin ◽  
A N Kamarudzaman ◽  
N R Rahmat ◽  
Z Hassan ◽  
M Abdul Wahab ◽  
...  
Keyword(s):  
Experimental Data ◽  
Kinetic Model ◽  
Freundlich Isotherm ◽  
Isotherm Models ◽  
Operating Parameters ◽  
Contact Period ◽  
Order Kinetic ◽  
Orange Peels ◽  
Tea Waste ◽  
Order Kinetic Model

Abstract The ability of biosorbents, which are a combination of orange peels and tea waste to treat copper (II) using the biosorption method was examined. The experiment was performed under batch biosorption studies with various operating parameters. The pH, biosorbent dosage, contact time, and initial copper (II) concentration were optimized from pH 3 - 8, 0.25 - 1.0 g, 2 - 20 minutes and 10 - 100 mg/L, respectively. The findings found that a pH of 5.5, a biosorbent dosage of 0.75 g, a contact period of 5 minutes, and an initial copper (II) concentration of 10 mg/L were shown to be the best operating parameters for copper (II) biosorption. For isotherm models, the experimental data for copper (II) biosorption was fitted to the Langmuir isotherm with R2 value of 0.7775 compared to the Freundlich isotherm model with R2 value of 0.1073. The value for RL was 0.4, indicating that copper (II) biosorption using the combination of orange peels and tea waste is favourable. For kinetic models, the experimental data for copper (II) biosorption was well fitted to the pseudo-second-order kinetic model with R2 value of 0.9865 compared to the pseudo-first-order kinetic model with R2 value of 0.1006. In conclusion, the combination of orange peels and tea waste functions very well for biosorption of copper (II).

Competitive coordination of iron(III) and copper(II) ions with amidoximated polyacrylonitrile nanofiber and the catalytic performance of the complex

2021 ◽  
pp. 152808372110639
Author(s):  
Fu Li ◽  
Pengfei Fei ◽  
Yongchun Dong ◽  
Man Zhang ◽  
Yu Feng ◽  
...  
Keyword(s):  
Metal Ions ◽  
Synergistic Effects ◽  
Binary Solution ◽  
Dye Adsorption ◽  
Freundlich Isotherm ◽  
Degradation Process ◽  
Catalytic Performance ◽  
Isotherm Models ◽  
Initial Concentration ◽  
Competitive Coordination

This present work describes the competitive coordination of iron (III) and copper (II) ions with amidoximated polyacrylonitrile nanofiber and the catalytic performance of the resulting complex (Fe-Cu-AO- n-PAN). The coordination results showed that the increase of the initial concentration of metal ions was beneficial to the increase of the coordination amount. There were both competition and synergistic effects between the two metal ions. But AO- n-PAN was more inclined to coordinate with Fe3+ ions. The promotion effect of Cu2+ ions on iron coordination due to weak positive electric property and small ion radius increased with its initial concentration in the solution. The Langmuir-Freundlich isotherm model among of four selected isotherm models for binary system showed the best fit to the co-coordination reaction between AO- n-PAN and Fe3+-Cu2+ binary solution. Fe-Cu-AO- n-PAN as heterogeneous Fenton catalyst displayed improved catalytic performance than mono-metal complexes due to its better dye adsorption and the synergistic effect between Cu2+ and Fe3+ ions during degradation process, and both the alkali-resistant and the reusability of it were improved at the same time.

scholarly journals Removal of Cr(VI) and Cu(II) Ions from Aqueous Solution by Carbon Prepared from Henna Leaves

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
T. Shanthi ◽  
V. M. Selvarajan
Keyword(s):  
Contact Time ◽  
Metal Ion ◽  
Metal Removal ◽  
Ph Value ◽  
Freundlich Isotherm ◽  
Isotherm Models ◽  
Lawsonia Inermis ◽  
Experimental Conditions ◽  
Initial Concentration ◽  
Adsorbent Dosage

Carbon prepared from leaves of henna (Lawsonia inermis) was used to study the adsorption of Cr(VI) and Cu(II) ions from their aqueous solutions. The experimental conditions which include pH, contact time, initial concentration, and adsorbent dosage on the metal removal were investigated. The capacity of adsorption depends on pH value; it increases with an increase in pH value from 1 to 7 and then decreases. The highest percentage of metal removal was achieved in the adsorbent dosage of 0.7 g and at an initial concentration of 100 ppm metal ion. The adsorption isotherm studies revealed that data was confirmed with both the Langmuir and Freundlich isotherm models. The removal percentage was found to be higher for Cu(II) when compared with Cr(VI). The potential of carbon prepared from henna leaves for the removal of these two solutions containing heavy metals was substantiated.

scholarly journals Determination of Adsorption Isotherm Models for the Biosorption of Chromium Using Cherry Leaves (Muntingia calabura L.)

2014 ◽  
Vol 25 ◽  
pp. 12-17
Author(s):  
R. Aathithya ◽  
J. Rajani Sowparnika ◽  
V. Balakrishnan
Keyword(s):  
Heavy Metal ◽  
Adsorption Isotherm ◽  
Freundlich Isotherm ◽  
Isotherm Models ◽  
Major Threat ◽  
Chromium Vi ◽  
Adsorption Affinity ◽  
Adsorption Isotherm Models ◽  
Muntingia Calabura

Contaminations of industrial metals into the river possess major threat to environment. Chromium is a heavy metal which has the wide applications in tannery and electroplating industries. Above the permitted level of Chromium(VI) into surface water leads to severe health hazards. Therefore, biosorption is a technology used for the sorption of heavy metal. In this present study adsorption isotherm models was studied for the biosorption of chromium by cherry leaves. From the adsorption isotherms it was found that the experimental data fits well with the Langmuir isotherm than the Freundlich isotherm. The monolayer capacity Qm was fond to be 11.98 mg/l and the adsorption affinity was found to be positive which indicates the efficient biosorption of chromium

scholarly journals Application Of Activated Candlenut Shell Using Potassium Hydroxide For Iron Reduction (Fe TO FeSO4)

2019 ◽  
Vol 4 (2) ◽  
pp. 63-67
Author(s):  
Wara Dyah Pita Rengga ◽  
Maharani Rani ◽  
Ashar Shidqi
Keyword(s):  
Activated Carbon ◽  
Adsorption Capacity ◽  
Potassium Hydroxide ◽  
Iron Reduction ◽  
Freundlich Isotherm ◽  
Isotherm Models ◽  
Activation Process ◽  
Activation Time ◽  
Initial Concentration ◽  
A Value

This study aims to prepare carbon from candlenut shell by carbonation and activation of 1M KOH which is used to adsorb Fe 2+ in solution. The activation process produces changes in structure and functional groups on activated carbon. This study studied the effect of carbonation temperatures of 800 o C with the concentration of activator is KOH 1M with 24 hours activation time. The initial concentration of the solution affects the adsorption capacity of activated carbon, the greater the initial concentration of the solution which is at 5 mg/L, the greater the adsorption capacity. Optimum adsorption occurs at pH 7 by providing an increase of Fe 2+ absorption of ± 7 mg/g and contact time is 120 minutes. The equilibrium review is used using the Langmuir and Freundlich isotherm models , where the most suitable equilibrium is the Freundlich Isotherm model with a value of R 2 = 0.9 848 ; K F = 4,427 ; n = 3,475 . It can be concluded that the activated carbon from the candlenut shell is able to absorb Fe 2+ metal in FeSO 4 solution.

Sign in / Sign up

Export Citation Format

Share Document