scholarly journals Sorption Behavior of Methylene Blue From Aqueous Solution By Using PVA/SA/Kaolin Composite

This research shows a method of elimination of methylene blue from aqueous solutions using PVA/SA/Kaolin Composite. The prepared was characterized by Fourier transform infra red spectroscopy (FTIR), X-Ray diffractogram (XRD), Thermo gravimetric analysis (TGA) and Scanning electron microscopic (SEM). Furthermore, the analyses of batch mode experiments were performed to study the experimental important parameters such as pH, metal ion concentrations, adsorbent dosages and contact time are discussed. From the experimental data, the adsorption isotherms are well described by Langmuir and Freundlich model, the adsorption of methyleneblue was fitted with Freundlich isotherm confirms the physical adsorption phenomena involved in this process. The kinetic parameter was correlated with the pseudo-second-order kinetic model. From the results, it was concluded that the material of PVA/SA/Kaolin Composite is an excellent adsorbent for the removal of methylene blue dye from aqueous solution.

2021 ◽  
Vol 33 (2) ◽  
pp. 471-483
Author(s):  
Patience Mapule Thabede ◽  
Ntaote David Shooto ◽  
Eliazer Bobby Naidoo

Present study reports on the sorption study of chromium(VI), cadmium(II) ions and methylene blue dye by pristine, defatted and carbonized Nigella sativa L. seeds from aqueous solution. The removal of oil from pristine Nigella sativa L. (PNS) seeds was carried out by defatting the Nigella sativa with acetone and N,N-dimethylformamide and then labelled ANS and DNS, respectively. Thereafter the defatted ANS and DNS adsorbents were carbonized at 600 ºC for 2 h under nitrogen and labelled as CANS and CDNS. The results of pristine, defatted and carbonized seeds were compared. The removal of Cr(VI), Cd(II) and methylene blue dye from aqueous solutions was investigated by varying adsorbate concentration, solution pH, reaction contact time and temperature of the solution. The SEM images indicated that the surface morphology of PNS was irregular, whilst ANS and DNS had pores and cavities. CANS and CDNS was heterogeneous and had pores and cavities. FTIR spectroscopy showed that the adsorbents surfaces had bands that indicated a lot of oxygen containing groups. The pH of the solution had an influence on the removal uptake of Cr(VI), Cd(II) and methylene blue. The sorption of Cr(VI) decreased when pH of the solution was increased due to different speciation of Cr(VI) ions whilst the removal of Cd(II) and methylene blue increased when solution pH was increased. Pseudo first order kinetic model well described the adsorption of Cr(VI), Cd(II) and methylene blue onto PNS. On the other hand, the kinetic data for ANS, CANS, DNS and CDNS was well described by pseudo second order. Furthermore, the removal mechanism onto PNS and ANS was better described by Freundlich multilayer model. The CANS, DNS and CDNS fitted Langmuir monolayer model. Thermodynamic parameters indicated that the sorption processes of Cr(VI), Cd(II) and methylene blue was endothermic and effective at high temperatures for all adsorbents. The ΔSº and ΔHº had positive values this confirmed that the sorption of Cr(VI), Cd(II) and methylene blue onto all adsorbents was random and endothermic, respectively. The values of ΔGº confirmed that the sorption of Cr(VI), Cd(II) and methylene blue on all adsorbents was spontaneous and predominated by physical adsorption process. The CANS had highest adsorption capacity of 99.82 mg/g for methylene blue, 96.89 mg/g for Cd(II) and 87.44 mg/g for Cr(VI) followed by CDNS with 93.90, 73.91 and 65.38 mg/g for methylene blue, Cd(II) and Cr(VI), respectively. The ANS capacities were 58.44, 45.28 and 48.96 mg/g whilst DNS capacities were 48.19, 32.69 and 34.65 mg/g for methylene blue, Cd(II) and Cr(VI), respectively. PNS had the lowest sorption capacities at 43.88, 36.01 and 19.84 mg/g for methylene blue, Cd(II) and Cr(VI), respectively.


Author(s):  
Saraa Muwafaq Ibrahim ◽  
Ziad T. Abd Ali

Batch experiments have been studied to remove methylene blue dye (MB) from aqueous solution using modified bentonite. The modified bentonite was synthesized by replacing exchangeable calcium cations in natural bentonite with cationic surfactant cetyl trimethyl ammonium bromide (CTAB). The characteristics of modified bentonite were studied using different analysis such as Scanning electronic microscopy (SEM), Fourier transform infrared spectrometry (FTIR) and surface area. Where SEM shows the natural bentonite has a porous structure, a rough and uneven appearance with scattered and different block structure sizes, while the modified bentonite surface morphology was smooth and supplemented by a limited number of holes. On other hand, (FTIR) analysis that proved NH group aliphatic and aromatic group of MB and silanol group are responsible for the sorption of contaminate. The organic matter peaks at 2848 and 2930 cm-1 in the spectra of modified bentonite which are sharper than those of the natural bentonite were assigned to the CH2 scissor vibration band and the symmetrical CH3 stretching absorption band, respectively, also the 2930 cm-1 peak is assigned to CH stretching band. The batch study was provided the maximum removal efficiency (99.99 % MB) with a sorption capacity of 129.87 mg/g at specified conditions (100 mg/L, 25℃, pH 11 and 250rpm). The sorption isotherm data fitted well with the Freundlich isotherm model. The kinetic studies were revealed that the sorption follows a pseudo-second-order kinetic model which indicates chemisorption between sorbent and sorbate molecules.


2022 ◽  
Vol 0 (0) ◽  
Author(s):  
Md. Nabul Sardar ◽  
Nazia Rahman ◽  
Shahnaz Sultana ◽  
Nirmal Chandra Dafader

Abstract This study focuses on the adsorption of hazardous Cr (III) and Cu (II) ions from aqueous solution by applying modified waste polypropylene (PP) fabric as an adsorbent. Pre-irradiation technique was performed for grafting of sodium styrene sulfonate (SSS) and acrylic acid (AAc) onto the PP fabric. The monomer containing 8% SSS and 16% AAc in water was used. Graft yield at 30 kGy radiation dose was 390% when 4% NaCl was added as additive. The prepared adsorbent was characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), thermo-gravimetric analysis (TGA) and dynamic mechanical analyzer (DMA). The influences of different parameters including pH, contact time, temperature and initial metal ion concentration were also investigated. The equilibrium adsorption data were better fitted to the Langmuir isotherm model with maximum monolayer adsorption capacity 384.62 mg/g for Cr (III) and 188.68 mg/g for Cu (II) ions. The kinetic data were better explained by pseudo first-order kinetic model having good matching between the experimental and theoretical adsorption capacity. The adsorption process was spontaneous, endothermic and thermodynamically feasible. Furthermore, investigation of desorption of metal ions and reuse of the adsorbent suggesting that the adsorbent is an efficient and alternative material in the removal of Cr (III) and Cu (II) from aqueous media.


2019 ◽  
Vol 4 (1-2) ◽  
pp. 1-6
Author(s):  
M. Mahadeva Swamy ◽  
B.M. Nagabhushana ◽  
Nagaraju Kottam

The present experiment explains the effectiveness of adsorption studies of methylene blue dye from aqueous solutions on activated carbon from Selenicereus grandiflorus (SG) treated with conc. sulfuric acid. The sulphuric acid-treated Selenicereus grandiflorus activated carbon (SGAC) was used as low-cost adsorbent for the removal of methylene blue dye from aqueous solution. It suggests an ideal alternative method to adsorption of dye compared to other expensive treatment options. The adsorption studies have been conducted at different experimental parameters, i.e., pH, contact time, adsorbent dose and initial dye concentration. The batch mode experiments were conducted by different adsorbent dose (0.03-0.150 g per 50 mL), pH of the solution (2-12), effect of time (3-18 min), initial dye concentration (10 mg/L), point of zero charge and regeneration of spent adsorbent studies. Langmuir model shows better fit to the equilibrium data (R2 = 0.966) than Freundlich model. The adsorption capacity (Qm) of SGAC increases with increasing dosage where Qm is 16.17 mg g-1.


Molecules ◽  
2019 ◽  
Vol 24 (23) ◽  
pp. 4205 ◽  
Author(s):  
Yang ◽  
Chai ◽  
Zeng ◽  
Gao ◽  
Zhang ◽  
...  

: Gel adsorption is an efficient method for the removal of metal ion. In the present study, a functional chitosan gel material (FCG) was synthesized successfully, and its structure was detected by different physicochemical techniques. The as-prepared FCG was stable in acid and alkaline media. The as-prepared material showed excellent adsorption properties for the capture of Cu2+ ion from aqueous solution. The maximum adsorption capacity for the FCG was 76.4 mg/g for Cu2+ ion (293 K). The kinetic adsorption data fits the Langmuir isotherm, and experimental isotherm data follows the pseudo-second-order kinetic model well, suggesting that it is a monolayer and the rate-limiting step is the physical adsorption. The separation factor (RL) for Langmuir and the 1/n value for Freundlich isotherm show that the Cu2+ ion is favorably adsorbed by FCG. The negative values of enthalpy (ΔH°) and Gibbs free energy (ΔG°) indicate that the adsorption process are exothermic and spontaneous in nature. Fourier transform infrared (FTIR) spectroscopy and x-ray photoelectron spectroscopy (XPS) analysis of FCG before and after adsorption further reveal that the mechanism of Cu2+ ion adsorption. Further desorption and reuse experiments show that FCG still retains 96% of the original adsorption following the fifth adsorption–desorption cycle. All these results indicate that FCG is a promising recyclable adsorbent for the removal of Cu2+ ion from aqueous solution.


2021 ◽  
Vol 21 (2) ◽  
pp. 421
Author(s):  
Aldes Lesbani ◽  
Neza Rahayu Palapa ◽  
Rabelia Juladika Sayeri ◽  
Tarmizi Taher ◽  
Nurlisa Hidayati

Ni/Al layered double hydroxide was used as a starting material for composite formation with biochar as a matrix. The materials were characterized using X-ray, FTIR, nitrogen adsorption-desorption, thermal, and morphology analyses. The NiAl LDH/Biochar material is then used as an adsorbent of methylene blue from an aqueous solution. The factor that was influencing adsorption such as pH, time, methylene blue concentration, and temperature adsorption was studied systematically. The regeneration of adsorbent was performed to know the stability of NiAl LDH/Biochar under several cycle adsorption processes. The results showed that NiAl LDH/Biochar has a specific diffraction peak at 11.63° and 22.30°. NiAl LDH/Biochar has more than ten-fold surface area properties (438,942 m2/g) than biochar (50.936 m2/g), and Ni/Al layered double hydroxide (92.682 m2/g). The methylene blue adsorption on NiAl LDH/Biochar follows a pseudo-second-order kinetic adsorption model and classify as physical adsorption. The high reusability properties were found for NiAl LDH/Biochar, which was largely different from biochar and Ni/Al layered double hydroxide.


2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Asma Nasrullah ◽  
Hizbullah Khan ◽  
Amir Sada Khan ◽  
Zakaria Man ◽  
Nawshad Muhammad ◽  
...  

The ash ofC. polygonoides(locally called balanza) was collected from Lakki Marwat, Khyber Pakhtunkhwa, Pakistan, and was utilized as biosorbent for methylene blue (MB) removal from aqueous solution. The ash was used as biosorbent without any physical or chemical treatment. The biosorbent was characterized by using various techniques such as Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). The particle size and surface area were measured using particle size analyzer and Brunauer-Emmett-Teller equation (BET), respectively. The SEM and BET results expressed that the adsorbent has porous nature. Effects of various conditions such as initial concentration of methylene blue (MB), initial pH, contact time, dosage of biosorbent, and stirring rate were also investigated for the adsorption process. The rate of the adsorption of MB on biomass sample was fast, and equilibrium has been achieved within 1 hour. The kinetics of MB adsorption on biosorbent was studied by pseudo-first- and pseudo-second-order kinetic models and the pseudo-second-order has better mathematical fit with correlation coefficient value (R2) of 0.999. The study revealed thatC. polygonoidesash proved to be an effective, alternative, inexpensive, and environmentally benign biosorbent for MB removal from aqueous solution.


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.


2012 ◽  
Vol 430-432 ◽  
pp. 197-201
Author(s):  
Feng Yu Li ◽  
Sheng Hua Zhang ◽  
Jin Yi Chen

Pyromellitic dianhydride(PMDA)- modified grain sorghum stalk was used as a novel low-cost adsorbent to remove cationic dye methylene blue(MB) from aqueous solution. Bath studies were carried out to investigate the effects of pH and retention time on the adsorption of MB. The adsorption process could obtain >98% removal percentage within 30 minutes as the MB concentration was at 200 and 300 mg/L. And for 400 mg/L MB, 99% was removed in 6 hrs. The kinetics study showed that the adsorption processes followed the pseudo-second-order kinetic model, which confirming that the sorption rate is controlled by chemical adsorption. Equilibrium isotherms were analyzed by the Langmuir and Freundlich models. Langmuir model can be fitted better than Freundlich with maximum monolayer adsorption capacity of 568.18 mg/g for MB.


2020 ◽  
Vol 20 (4) ◽  
pp. 755
Author(s):  
Nurul Ain Safiqah Md Sandollah ◽  
Sheikh Ahmad Izaddin Sheikh Mohd Ghazali ◽  
Wan Nazihah Wan Ibrahim ◽  
Ruhaida Rusmin

The efficiencies of raw (RK) and acid activated (0.5 M AAK) kaolinite clay minerals to remove methylene blue (MB) dyes in aqueous solution were investigated and compared. The 0.5 M AAK was prepared by treatment of RK in dilute 0.5 M HCl aqueous solution under reflux. Kaolinite adsorbents were characterized and their MB removal performances were evaluated via the batch method. MB desorption from spent kaolinites was investigated at pH 4 to 8. The MB removal was increased with increasing initial dye concentration, agitation speed and adsorbent dosage in 60 min reaction time at pH 6. Both kaolinites showed high MB removal (up to 97%). The Freundlich model has the best-fit equilibrium adsorption isotherm model for RK and 0.5 M AAK. The kinetic data for both adsorbents showed strong agreement with the pseudo second order kinetic model (r2 > 0.98). Nevertheless, the spent RK adsorbent demonstrated a significant higher MB retention than 0.5 M AAK in desorption experiments. Kaolinite clays have great potential as cost-effective materials for dyes removal in wastewater treatment.


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