Kinetic and isotherm studies on adsorption of methylene blue using polyacrylonitrile/hydroxyl group functionalized multiwall carbon nanotube multilayered nanofibrous composite

2020 ◽  
pp. 009524431989728
Author(s):  
S Swaminathan ◽  
NM Imayathamizhan ◽  
A Muthumanickkam

Nanofibrous composite mat was prepared using polyacrylonitrile hard yarn waste and hydroxyl group functionalized multiwall carbon nanotubes (MWCNTs-OH) by electrospinning technique and exploit for methylene blue dye adsorption from aqueous solution. The nanofibrous composite mat was characterized by Fourier transform (FT) infrared spectroscopy, FT-Raman, scanning electron microscopy, X-ray diffractometer and thermogravimetric analyser. The adsorption experiments were studied to investigate the effect of MWCNT-OH weight percentage, initial solution pH, contact time and initial dye concentration on the adsorption. The higher percentage of methylene blue adsorption was found to be 80.05% under optimal condition. The adsorption equilibrium data were studied with Langmuir and Freundlich isotherm models. The R2 value was found to be higher in the Freundlich isotherm model which was clearly indicated that the Freundlich isotherm model is most suitable for the adsorption of methylene blue on nanofibrous composite mat. The kinetic study was carried out to explain the adsorption rate of methylene blue on nanofibrous composite. The kinetic study of methylene blue adsorption was favourable to the pseudo second-order equation.

Author(s):  
Subramanian Swaminathan ◽  
Nallammal Muthupaiyan Imayathamizhan ◽  
Andiyappan Muthumanickam ◽  
Pooncholai Moorthi

Abstract Polyacrylonitrile yarn hard waste and multiwall carbon nano-tubes nanofibrous mat was prepared by the electrospinning technique. The nanofibrous composite mats were characterized using thermo-gravimetric analysis, Fourier transform infrared spectroscopy, FT-Raman, scanning electron microscopy, and X-ray diffraction. Adsorption studies were conducted with various physical and chemical parameters such as contact time, solution pH and initial dye concentration. The maximum methylene blue dye removal efficiency of nanofibrous composite was found to be 73.4%at optimized pH 10. The pseudo-second order kinetics and Freundlich isotherm are suitable for methylene blue dye adsorption of nanofibrous composite.


2016 ◽  
Vol 75 (5) ◽  
pp. 1138-1147 ◽  
Author(s):  
Manash Deep Dey ◽  
Minhaz Ahmed ◽  
Ranjana Singh ◽  
Ratan Boruah ◽  
Rupak Mukhopadhyay

Fresh water streams contaminated with synthetic dye-containing effluents pose a threat to aquatic and human life either by preventing aquatic photosynthesis or by entering into the food chain. Adsorptive removal of such dyes with potent biosorbents is an important technique to reduce bioaccumulation and biomagnifications of the dyes in human life. We report use of betel nut (BN) husk and banana peel (BP), two most abundant ligno-cellulosic wastes, as efficient adsorbents for the removal of the basic dye methylene blue (MB). The adsorption by BN and BP was consistently high over wide ranges of pH and temperature, suggesting their dye removal potential in diverse conditions. Physico-chemical studies, e.g. scanning electron microscopy and Fourier transform-infrared spectroscopy studies, revealed changes in surface topology and functional moieties of BN and BP post adsorption, implying dye interaction with the biomass surface. The dye adsorption in both cases followed pseudo-second-order kinetics. While adsorption of MB by BN was better fitted with the Temkin isotherm model, adsorption with BP followed both Langmuir and Freundlich isotherm models. Our studies concluded that both adsorbents efficiently remove MB from its aqueous solution with BP proved to be marginally superior to BN.


2015 ◽  
Vol 72 (6) ◽  
pp. 896-907 ◽  
Author(s):  
S. M. Anisuzzaman ◽  
Collin G. Joseph ◽  
D. Krishnaiah ◽  
A. Bono ◽  
L. C. Ooi

In this study, durian (Durio zibethinus Murray) skin was examined for its ability to remove methylene blue (MB) dye from simulated textile wastewater. Adsorption equilibrium and kinetics of MB removal from aqueous solutions at different parametric conditions such as different initial concentrations (2–10 mg/L), biosorbent dosages (0.3–0.7 g) and pH solution (4–9) onto durian skin were studied using batch adsorption. The amount of MB adsorbed increased from 3.45 to 17.31 mg/g with the increase in initial concentration of MB dye; whereas biosorbent dosage increased from 1.08 to 2.47 mg/g. Maximum dye adsorption capacity of the durian skin was found to increase from 3.78 to 6.40 mg/g, with increasing solution pH. Equilibrium isotherm data were analyzed according to Langmuir and Freundlich isotherm models. The sorption equilibrium was best described by the Freundlich isotherm model with maximum adsorption capacity of 7.23 mg/g and this was due to the heterogeneous nature of the durian skin surface. Kinetic studies indicated that the sorption of MB dye tended to follow the pseudo second-order kinetic model with promising correlation of 0.9836 < R2 < 0.9918.


2019 ◽  
Vol 948 ◽  
pp. 26-32
Author(s):  
Galuh Yuliani ◽  
Siska Mutiara ◽  
Agus Setiabudi

The amount of coal combustion byproducts, such as fly ash and bottom ash, generated by coal-based thermal power plants has been increasing at an alarming rate, hence creating huge problems on their treatments and disposals. One of the promising approaches for proper utilization of these byproducts is the conversion of fly ash and bottom ash to zeolites. In this research, zeolites wereprepared from coal bottom ash (RBA) by relatively simple and cheap conversion process using NaOH at 90°C for 24h. Prior to this, the RBA was pretreated using H2SO4 for 4h. The resulted zeolite was characterized using X-ray diffraction (XRD), X-ray fluorescence (XRF), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). XRD results confirmed the formation of sodium aluminosilicate hydrate predominated upon the bottom ash and NaOH 5M ratio of 1:8. XRF results also indicated the domination of Al2O3 and SiO2 in the zeolite composition. FTIR spectra showed characteristic zeolite peaks at 900-1100, 400-500 and 550-660 cm–1forSi-O, Al-O, and Si-O-Al absorptions, respectively. The synthetic zeolite was then applied as an adsorbent for lignin and methylene blue in aqueous solutions. It was found that the Qmax for lignin and methylene blue was16.13 mg/g and 34.13 mg/g, respectively. When fitted using Langmuir and Freundlich isotherm models, the methylene blue adsorption data fitted Langmuir isotherm while those of lignin fitted Freundlich isotherm. It was concluded that the chemical interaction between zeolite and methylene blue may lead to the chemisorption mechanism to prevail.


2017 ◽  
Vol 751 ◽  
pp. 671-676 ◽  
Author(s):  
Tawan Chaiwon ◽  
Panatda Jannoey ◽  
Duangdao Channei

This research aimed to study the preparation of activated carbon from sugarcane bagasse waste. The sugarcane bagasse adsorbent was prepared by calcination at 600°C for 2 hours with the use of sulfuric acid (H2SO4) as a chemical activation. The adsorption surface possessed high specific surface area (838 m2/g) with mesoporous diameter. Factors explaining adsorption including adsorption isotherm, adsorption kinetic and adsorption mechanism were constructed from methylene blue adsorption experiments. It was found that the equilibrium data was best represented by Freundlich isotherm, showing multilayer coverage of dye molecules at the outer surface of adsorbent with a cooperative adsorption (physisorption and chemisorption). The kinetic of methylene blue adsorption was found to follow pseudo-second-order rate kinetic model, with a good correlation coefficient. This indicated that the overall rate of the dye adsorption process was controlled by the chemisorption process.


2021 ◽  
Vol 2021 ◽  
pp. 1-16
Author(s):  
Hizkeal Tsade Kara ◽  
Sisay Tadesse Anshebo ◽  
Fedlu Kedir Sabir ◽  
Getachew Adam Workineh

The study was focused on the preparation and characterizations of sodium periodate-modified nanocellulose (NaIO4-NC) prepared from Eichhornia crassipes for the removal of cationic methylene blue (MB) dye from wastewater (WW). A chemical method was used for the preparation of NaIO4-NC. The prepared NaIO4-NC adsorbent was characterized by using X-ray diffraction (XRD), Fourier transform infrared (FTIR), scanning electron microscope (SEM), energy-dispersive X-ray (EDX), and Brunauer–Emmett–Teller (BET) instruments. Next, it was tested to the adsorption of MB dye from WW using batch experiments. The adsorption process was performed using Langmuir and Freundlich isotherm models with maximum adsorption efficiency (qmax) of 90.91 mg·g−1 and percent color removal of 78.1% at optimum 30 mg·L−1, 60 min., 1 g, and 8 values of initial concentration, contact time, adsorbent dose, and solution pH, respectively. Pseudo-second-order (PSO) kinetic model was well fitted for the adsorption of MB dye through the chemisorption process. The adsorption process was spontaneous and feasible from the thermodynamic study because the Gibbs free energy value was negative. After adsorption, the decreased values for physicochemical parameters of WW were observed in addition to the color removal. From the regeneration study, it is possible to conclude that NaIO4-NC adsorbent was recyclable and reused as MB dye adsorption for 13 successive cycles without significant efficient loss.


Author(s):  
L. Salami ◽  
D. O. Olumuyiwa ◽  
E. A. Alfred ◽  
O. S. Olakanmi

Dumpsite leachate has the potential to pollute ground and surface water as well as vegetation within the vicinity of the dumpsite.  Its treatment therefore needs adequate attention. The aim of this work is to study the adsorption of Soluos dumpsite leachate treatment using Musa sapientum peel as biosorbent with a view of establishing the adsorption isotherm model. Musa sapientum peels sourced from Ayetoro market in Epe area of Lagos State, Nigeria were used to prepare the adsorbent. Batch adsorption was carried out with various dosage of the prepared absorbent in leachate collected from Soluos dumpsite in Lagos. The adsorption data obtained were fitted into Linear, Freundlich, Langmuir, Temkin and Hasley isotherm models. The results showed that the concentration of total dissolved solids (TDS) in the dumpsite leachate decreased as the adsorbent dosage increased. At adsorbent dosage of 10 g/L, the concentration of TDS in the leachate was 485.7 mg/L which was less than the 500 mg/L stipulated by National Environmental Standard and Regulatory Agency (NAESRA) for the discharge of wastewater. The coefficient of determination (R2) values for Linear, Freundlich and Hasley, Langmuir and Temkin isotherm models were 0.9944, 0.9936, 0.8562 and 0.9723 respectively. Linear isotherm model was jettisoned because the plot did not pass through the origin and Freundlich isotherm model was ignored as a result of N value which was less than unity hence Hasley isotherm model was adopted in this work. A good correlation existed between the experimental and predicted values, having a R2 value of 0.9965 which further validated the Hasley isotherm model as the best adsorption model for the treatment of Soluos dumpsite leachate using Musa sapientum peel as biosorbent. It was concluded that Musa sapientum peel as biosorbent can be used for treatment of Soluos dumpsite leachate.


Polymers ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 1024 ◽  
Author(s):  
Gulzhian I. Dzhardimalieva ◽  
Rose K. Baimuratova ◽  
Evgeniya I. Knerelman ◽  
Galina I. Davydova ◽  
Sarkyt E. Kudaibergenov ◽  
...  

Several important synthesis pathways for metal-organic frameworks (MOFs) were applied to determine how the synthesis methods and conditions affect the structure and adsorption capacity of the resulting samples. In the present work, three different synthesis routes were used to obtain copper trimesinate coordination polymer: Slow evaporation (A), solvothermal synthesis using a polyethylene glycol (PEG-1500) modulator (B), and green synthesis in water (C). This MOF was characterized by elemental analysis, infrared spectrometry, X-ray diffraction, scanning electron microscopy, thermogravimetry and volumetric nitrogen adsorption/desorption. The samples have permanent porosity and a microporous structure with a large surface area corresponding to the adsorption type I. The obtained MOF was tested as a sorbent to remove organic dyes methylene blue (МВ), Congo red (CR) and methyl violet (MV) as examples. Dye adsorption followed pseudo-first-order kinetics. The equilibrium data were fitted to the Langmuir and Freundlich isotherm models, and the isotherm constants were determined. Thermodynamic parameters, such as changes in the free energy of adsorption (∆G0), enthalpy (∆H0), and entropy (∆S0), were calculated. Thermolysis of copper trimesinate leads to the formation of carbon materials Cu@C with a high purity.


2009 ◽  
Vol 2009 ◽  
pp. 1-9 ◽  
Author(s):  
Ji-Hoon Yang ◽  
Jae-Chan Lee ◽  
Seong-Ho Choi

The tyrosinase-immobilized biosensor was developed with the hydroxyl group-functionalized multiwall carbon nanotube (MWNT) for phenol detection. The hydroxyl group-modified MWNT was modified to include poly(GVPB)-g-MWNT, or poly(HEMA), by a radiation-induced graft polymerization of glucosyl 4-vinylphenylboronate (GVPB) or 2-hydroxyethyl methacrylate (HEMA) on the surface of MWNT. The response of biosensor was in the range of 0.6–7.0 mM for concentration and in the range of 0.05–0.35 mM for phenol in a phosphate buffer solution, respectively. Various parameters influencing biosensor performance have been optimized: for pH, temperature, and the response to various phenolic compounds. The biosensor was then tested on phenolic compounds contained in three different commercial red wines.


2020 ◽  
Vol 11 (2) ◽  
pp. 9227-9241

High amounts of ammonium (NH4+) discharged in receiving water can lead to eutrophication. The adsorption of NH4+ from synthetic solution onto granular activated carbon (GAC) was scrutinized with respect to initial solute concentration (10 mg L−1), solution volume (0.2 L), adsorbent dosage (4 – 20 g), and contact time. Experimental data can be well described by the pseudo-second-order kinetic model (R2 > 0.994) and Freundlich isotherm model (R2 = 0.936), suggesting that chemisorption and multilayer adsorption occurred. Furthermore, this study explored the feasibility of using the Freundlich isotherm model to estimate the removal efficiency or required amount of adsorbent. The result findings indicated that GAC has a good potential to adsorb NH4+ from water and thus giving new insights into environmental engineering practices.


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