scholarly journals Adsorption of Methylene Blue by Low-Cost Biochar Derived from Elephant Dung

2021 ◽  
pp. 34-44
Author(s):  
Yanasinee Suma ◽  
Nittaya Pasukphun ◽  
Numfon Eaktasang

Elephant dung biochar (ED350) prepared by controlled heating at 350 ºC was used to adsorb methylene blue (MB) in an aqueous solution. The effects of adsorption time, pH, adsorbent dosage, and initial MB concentration were examined. Kinetic, isotherm, and thermo-dynamic models were then further analyzed to determine the adsorption. The results show that ED350 was found to be efficient within 180 min. The optimum pH of MB adsorption was 11. The Langmuir isotherm model was found to be the most suitable fit for the adsorption equilibrium data, with ED350 having a homogeneous surface. The calculated equilibrium parameter (RL) values were greater than zero and less than one, indicating a favorable adsorption process and that ED350 was an efficient adsorbent for MB removal. The kinetics of MB adsorption onto ED350 obeys the pseudo-second-order model. The results of thermo-dynamic data consideration reveal that the adsorption process is spontaneous and exothermic in nature. This finding suggests that ED350 may prove to be an efficient low-cost adsorbent of MB from wastewater.

2018 ◽  
Vol 54 (1) ◽  
pp. 57-69 ◽  
Author(s):  
Shaheriar Haque ◽  
Sekhar Gain ◽  
Kaushik Gupta ◽  
Uday Chand Ghosh

Abstract Graphene oxide (GO) fabricated iron-aluminium oxide (GO@IAO) nanocomposite was synthesized with one-spot chemical reaction from emulsification of GO (1.0 g) in 0.2 L of 1.0 M mixed metal solution, which was characterized with some of the latest analytical tools aiming to assess methylene blue (MB) adsorption performance from aqueous solutions. Adsorption of MB on GO@IAO surfaces shows a steep increase from pH 3.0 to 5.0, but steepness declines at pH >5.0. The closeness of fitted kinetic data with the pseudo-second order (PSO) equation (R2 = 0.9845) compared to the pseudo-first order equation (R2 = 0.9527) confirms the adsorption process is of the PSO type. The MB adsorption equilibrium data can be described better by the Langmuir isotherm (R2 = 0.99) than the Freundlich isotherm (R2 = 0.96–0.97), inclining to the monolayer adsorption process. The Langmuir adsorption capacity of GO@IAO has been estimated to be 330.35 mg/g at 303 K. The MB adsorption is established to be spontaneous (–ΔG0 = 26.31–26.61 kJ/mol) owing to favourable enthalpy and entropy changes (ΔH0 = –23.38 kJ/mol; ΔS0= 0.01 kJ/mol/K). Both absolute and aqueous (1/1, v/v) alcohols regenerate the MB adsorbed GO@IAO up to 80–85%, indicating recyclability of composite.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Hakan Çelebi ◽  
Gülden Gök ◽  
Oğuzhan Gök

Abstract Recently, the search for low-cost eco-friendly adsorbents has become one of the main objectives of researchers. The aim of this study was to test the removal of four heavy metals, namely lead (Pb), zinc (Zn), nickel (Ni) and cadmium (Cd), from a simulated watery solution using brewed tea waste as a potentially suitable adsorbent. The effects of pH levels (2.0–6.0), adsorbent amount (0.1–5.0 g), contact times (1–150 min.) were examined throughout the adsorption process. The results of the experiments showed that the heavy metals elimination yields had an inverse relationship with pH and a linear relationship between the other parameters. The optimum pH for the removal of the heavy metals was between 4.0 and 5.0 in the case of the brewed tea waste. Equilibrium times of 2, 10, 30 and 5 min were required for the adsorption of Pb, Zn, Ni, Cd onto Camellia sinensis, respectively. Based on the results of this study it can be said that brewed tea waste has a high potential to remove heavy metals from aqueous solutions. The maximum adsorption capacities were calculated as 1.197, 1.457, 1.163 and 2.468 mg/g, for Pb, Zn, Ni and Cd, respectively, by fitting the equilibrium data to the Langmuir isotherm model.


2015 ◽  
Vol 69 (7) ◽  
Author(s):  
Mohammad Peydayesh ◽  
Mojgan Isanejad ◽  
Toraj Mohammadi ◽  
Seyed Mohammad Reza Seyed Jafari

AbstractMethylene blue (MB) removal using eco-friendly, cost-effective, and freely available Urtica was investigated. The morphology of the adsorbent surface and the nature of the possible Urtica and MB interactions were examined using SEM analysis and the FTIR technique, respectively. Various factors affecting MB adsorption such as adsorption time, initial MB concentration, temperature, and solution pH were investigated. The adsorption process was analysed using different kinetic models and isotherms. The results showed that the MB adsorption kinetic follows a pseudo-second-order kinetic model and the isotherm data fit the Langmuir isotherm well. Thermodynamic parameters, such as ΔG°, ΔH°, and ΔS°, were also evaluated, and the results indicated that the adsorption process is endothermic and spontaneous in nature. The MB adsorption capacity of Urtica was found to be as high as 101.01 mg g


2015 ◽  
Vol 72 (4) ◽  
Author(s):  
Mohd Ismid Mohd Said ◽  
Shaikhah Sabri ◽  
Shamila Azman

Contamination of metals in aquatic environment is a worldwide problem because of its toxicity and capability to accumulate in biological chain, as well as persistence in the natural environment. Therefore various expensive technologies have been applied to treat metal-polluted water. In Malaysia there are abundance of banana species available which could provide cheap, low cost and environmental friendly bio-materials. Preliminary study was conducted on two species of banana i.e. Musa balbisiana (Nipah) and Musa acuminata (Kapas). The banana peels were washed, dried and grounded into various range of particle sizes (0.20–1.18 mm). The ability of the adsorbents were determined by agitation of 1.0 g banana peel and 100 ml of cadmium standard solution at the concentration of 100 mg/L. Musa balbisiana showed the highest removal of cadmium at 89.58% from the initial concentration compared to Musa acuminate with the particle size of 0.30-0.60 mm. Adsorption equilibrium data are well described by Langmuir isotherm model. The result also shows that different species have different capabilities to adsorb metal. Hence, their potential as bio-adsorbent could be further be examined for metal removal from wastewater.


2015 ◽  
Vol 76 (13) ◽  
Author(s):  
Ahmed Salisu ◽  
Mohd Marsin Sanagi ◽  
Khairil Juhanni Abd Karim ◽  
Neda Pourmand ◽  
Wan Aini Wan Ibrahim

In this study, the removal of methylene blue (MB) dye using alginate-graft-poly (methyl methacrylate) beads was investigated. The effects of adsorption parameters namely initial pH and initial dye concentration were studied. The removal efficiency of the beads has been found to be dependent on initial dye concentration and initial pH. The experimental equilibrium data was fitted successfully to Langmuir isotherm model with the maximum monolayer coverage of 5.25 mg g−1 and adsorption kinetics data has been well fitted by a pseudo-second-order kinetic model. The alginate based beads could be used as low-cost and eco-friendly adsorbent for removal of trace amount of methylene blue from aqueous solution.


Processes ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 1279
Author(s):  
Wafa Mohammed Alghamdi ◽  
Ines El Mannoubi

Natural adsorbents as low-cost materials have been proved efficient for water remediation and have significant capacity for the removal of certain chemicals from wastewater. The present investigation aimed to use Citrullus colocynthis seeds (CCSs) and peels (CCPs) as an efficient natural adsorbent for methylene blue (MB) dye in an aqueous solution. The examined biosorbents were characterized using surface area analyzer (BET), scanning electron microscope (SEM), thermogravimetric analyzer (TGA) and Fourier transform infra-red (FT-IR) spectroscopy. Batch adsorption experiments were conducted to optimize the main factors influencing the biosorption process. The equilibrium data for the adsorption of MB by CCSs were best described by the Langmuir isotherm followed by the Freundlich adsorption isotherms, while the equilibrium data for MB adsorption by CCPs were well fitted by the Langmuir isotherm followed by the Temkin isotherm. Under optimum conditions, the maximum biosorption capacity and removal efficiency were 18.832 mg g−1 and 98.00% for MB-CCSs and 4.480 mg g−1 and 91.43% for MB-CCPs. Kinetic studies revealed that MB adsorption onto CCSs obeys pseudo-first order kinetic model (K1 = 0.0274 min−1), while MB adsorption onto CCPs follows the pseudo-second order kinetic model (K2 = 0.0177 g mg−1 min−1). Thermodynamic studies revealed that the MB biosorption by CCSs was endothermic and a spontaneous process in nature associated with a rise in randomness, but the MB adsorption by CCPs was exothermic and a spontaneous process only at room temperature with a decline in disorder. Based on the obtained results, CCSs and CCPSs can be utilized as efficient, natural biosorbents, and CCSs is promising since it showed the highest removal percentage and adsorption capacity of MB dye.


Nanomaterials ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1540
Author(s):  
Muhammad Ahmad ◽  
Tehseen Nawaz ◽  
Mohammad Mujahid Alam ◽  
Yasir Abbas ◽  
Shafqat Ali ◽  
...  

The development of excellent drug adsorbents and clarifying the interaction mechanisms between adsorbents and adsorbates are greatly desired for a clean environment. Herein, we report that a reduced graphene oxide modified sheeted polyphosphazene (rGO/poly (cyclotriphosphazene-co-4,4′-sulfonyldiphenol)) defined as PZS on rGO was used to remove the tetracycline (TC) drug from an aqueous solution. Compared to PZS microspheres, the adsorption capacity of sheeted PZS@rGO exhibited a high adsorption capacity of 496 mg/g. The adsorption equilibrium data well obeyed the Langmuir isotherm model, and the kinetics isotherm was fitted to the pseudo-second-order model. Thermodynamic analysis showed that the adsorption of TC was an exothermic, spontaneous process. Furthermore, we highlighted the importance of the surface modification of PZS by the introduction of rGO, which tremendously increased the surface area necessary for high adsorption. Along with high surface area, electrostatic attractions, H-bonding, π-π stacking and Lewis acid-base interactions were involved in the high adsorption capacity of PZS@rGO. Furthermore, we also proposed the mechanism of TC adsorption via PZS@rGO.


2012 ◽  
Vol 9 (3) ◽  
pp. 1457-1480 ◽  
Author(s):  
R. Bhaumik ◽  
N. K. Mondal ◽  
B. Das ◽  
P. Roy ◽  
K. C. Pal ◽  
...  

A new medium, eggshell powder has been developed for fluoride removal from aqueous solution. Fluoride adsorption was studied in a batch system where adsorption was found to be pH dependent with maximum removal efficiency at 6.0. The experimental data was more satisfactorily fitted with Langmuir isotherm model. The kinetics and the factor controlling adsorption process fully accepted by pseudo-second-order model were also discussed. Eawas found to be 45.98 kJmol-1by using Arrhenius equation, indicating chemisorption nature of fluoride onto eggshell powder. Thermodynamic study showed spontaneous nature and feasibility of the adsorption process with negative enthalpy (∆H0) value also supported the exothermic nature. Batch experiments were performed to study the applicability of the adsorbent by using fluoride contaminated water collected from affected areas. These results indicate that eggshell powder can be used as an effective, low-cost adsorbent to remove fluoride from aqueous solution as well as groundwater.


2012 ◽  
Vol 550-553 ◽  
pp. 2259-2262
Author(s):  
Song Bo Cui ◽  
Hua Yong Zhang ◽  
Lu Yi Zhang

The adsorption behavior of methylene blue (MB) dye from aqueous solutions onto honeycomb-cinder (HC) and its acid-activated product was investigated in a batch system. The results showed the adsorption capacity was decreased for raw HC samples with the increase of pH value, while it was increased for activated samples. The adsorption data were fit with Langmuir isotherm model for MB adsorption by all samples. The MB adsorption capacity on samples was increased from 2.62 mg/g to 7.81 mg/g and 7.00 mg/g after acid-activated by HCl and H2SO4, respectively. The adsorption processes of MB followed pseudo-second-order kinetics with a coefficient of correlation≥0.99. This study demonstrated that acid-activated HC has superior adsorbing ability for MB than raw HC and can be used as alternative adsorbents in dye wastewater treatment.


2021 ◽  
Author(s):  
Nur Shazwani Abdul Mubarak ◽  
N.N. Bahrudin ◽  
Ali H. Jawad ◽  
B.H. Hameed ◽  
Sumiyyah Sabar

Abstract In this work, sulfonated chitosan montmorillonite composite (S-CS-MT) beads were synthesized using a microwave irradiation method designed to have a better saving-time procedure. The potency of S-CS-MT as an adsorbent was assessed for the removal of cationic dyes such as methylene blue (MB) from aqueous solution. The batch adsorption experiments indicated that MB adsorption onto S-CS-MT follows the Pseudo-second-order kinetic and Langmuir isotherm model. The maximum extent obtained from the Langmuir isotherm model for MB adsorption was 188.2 mg g− 1 at 303 K. The thermodynamic study indicated that the adsorption reaction is favorable and spontaneous. These findings indicated that montmorillonite chitosan grafted with the sulfonate group has the ability and efficacy as biohybrid adsorbent for the adsorption of cationic dyes.


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