scholarly journals Grewia spp. Biopolymer as Low-Cost Biosorbent for Hexavalent Chromium Removal

2019 ◽  
Vol 2019 ◽  
pp. 1-7 ◽  
Author(s):  
G. P. Kofa ◽  
G. R. Nkoue Ndongo ◽  
M. B. Kameni Ngounou ◽  
M. N. Nsoe ◽  
E. V. Amba ◽  
...  

In this study, Grewia spp. biopolymer was utilized as a biosorbent for elimination of hexavalent chromium from water. Fourier-transform infrared spectrometry (FTIR) and X-ray diffraction (XRD) were performed for characterization of the biosorbent. Experiments were conducted in a batch mode at room temperature (25 ± 2°C) and agitation speed of 100 rpm to determine the influence of biosorbent dose, contact time, Cr(VI) concentration, and initial solution pH. It was found that equilibrium was attained in 50 min. A pseudo-first-order model suited well than a pseudo-second-order model. Biosorption capacity of Grewia spp. biopolymer increased with increase in concentration and depended on the solution pH. Langmuir and Freundlich models described experimental data very well. These findings showed that Grewia spp. biopolymer can serve as a biosorbent for elimination of Cr(VI) from water.

2020 ◽  
Vol 2020 ◽  
pp. 1-14
Author(s):  
A. Thiam ◽  
K. Tanji ◽  
O. Assila ◽  
M. Zouheir ◽  
Redouane Haounati ◽  
...  

In this work, the adsorption of Remazol Brilliant Blue (RBB) over raw date pits (RDPs) as an inexpensive adsorbent has been examined. In addition, all parameters such as the adsorbent mass, solution pH, RDP particle size, RBB initial concentration, and temperature on the adsorption of RBB influencing the adsorption procedure were studied to provide fundamental information of the adsorption equilibrium. The characterization of RDP material is investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier-transform infrared spectroscopy (FTIR). Based on the calculation, the kinetic rate of the adsorption was well modeled by pseudo-second-order and Langmuir isotherm. Surface functional groups of RDP have substantially been influenced by the adsorption characteristics of RBB. The capacity of the adsorption has achieved 105 mg/g and a removal efficiency of 90.4% at 1.5 g/L RDP mass, 40 mg/L initial dye concentration, pH 2, temperature of 328 K, 40 µm particle size, and contact time of 50 min. The capacity of the adsorption could reach 198 mg/g by increasing the ionic strength of RBB solution. Desorption tests showed that RDP adsorbent has the disadvantage of losing efficiency while reusing for many cycles. However, it still abundant and inexpensive. Therefore, RDP can be used as a potential low-cost bioabsorbent for the elimination of RBB from wastewater.


2019 ◽  
Vol 800 ◽  
pp. 187-192 ◽  
Author(s):  
Halima Delali ◽  
Djilali Redha Merouani ◽  
Hakim Aguedal ◽  
Mustapha Belhakem ◽  
Abdelkader Iddou ◽  
...  

In the present study, the waste shells were used as a new low cost and eco-friendly biosorbant for Orange G anionic dye removal from aqueous solutions. Experiments were conducted in batch mode, and the effect of pH of solution, contact time, and initial dye concentration. X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and ICP-MS analysis for chemical analysis were used to characterize the obtained biosorbent. The results showed that the mussel shells are composed 73% of calcite and 26% of aragonite with some traces of aluminum, magnesium, sodium, silicium and zinc. The biosorption results show that the optimal pH was around 2 for efficient Orange G biosorption. The equilibrium was attained in 60 min. The kinetic analysis showed that the pseudo-second-order model is in good agreement with the experimental data. The biosorption isotherm was well described by Langmuir isotherm model, the maximumbiosorption capacity was 1000mg/g. The thermodynamic study revealed that the biosorption of Orange G onto mussel shell is spontaneous and exothermic.


2020 ◽  
Vol 38 (9-10) ◽  
pp. 483-501
Author(s):  
Nguyen Thi Huong ◽  
Nguyen Ngoc Son ◽  
Vo Hoang Phuong ◽  
Cong Tien Dung ◽  
Pham Thi Mai Huong ◽  
...  

The Fe3O4/Talc nanocomposite was synthesized by the coprecipitation-ultrasonication method. The reaction was carried out under a inert gas environment. The nanoparticles were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), fourier-transform infrared spectroscopy (FT-IR) and vibrating sample magnetometry techniques (VSM), the surface area of the nanoparticles was determined to be 77.92 m2/g by Brunauer-Emmett-Teller method (BET). The kinetic data showed that the adsorption process fitted with the pseudo-second order model. Batch experiments were carried out to determine the adsorption kinetics and mechanisms of Cr(VI) by Fe3O4/Talc nanocomposite. The adsorption process was found to be highly pH-dependent, which made the material selectively adsorb these metals from aqueous solution. The isotherms of adsorption were also studied using Langmuir and Freundlich equations in linear forms. It is found that the Langmuir equation showed better linear correlation with the experimental data than the Freundlich. The thermodynamics of Cr(VI) adsorption onto the Fe3O4/Talc nanocomposite indicated that the adsorption was exothermic. The reusability study has proven that Fe3O4/Talc nanocomposite can be employed as a low-cost and easy to separate.


2020 ◽  
pp. 13-22

Hexavalent chromium (Cr(VI)) has the characteristic of forming anionic species, which are very toxic, very soluble in water and difficult to be removed. In this study, dichromate removal from aqueous solutions by chitosan and chitosan modified by sodium dodecyl sulfate (SDS) was addressed. The effect of various experimental parameters, such as pH (1-9), initial concentration (10-100 mg L-1), adsorbent dose (0.005-0.350 g) and contact time (5-60 min) was investigated. All experiments were conducted in batch mode at room temperature (~21 oC). The obtained equilibrium adsorption isotherms were analyzed using the Langmuir and Freundlich models. Furthermore, the kinetics of dichromate removal was analyzed by pseudo-first order, pseudo-second order and the Elovich models. Optimum conditions for obtaining high removal (~97%) within a relatively short time (60 min) are: 5.0 pH, 0.100 g SDS-chitosan dosage and an initial Cr2O72- concentration of 10 mg L-1. The dichromate adsorption capacity of chitosan is 8.3 mg L-1, while that of SDS-chitosan is 9.7 mg L-1. In addition, the adsorption of dichromate by chitosan and SDS-chitosan is well-fitted by the Langmuir and Freundlich models while the adsorption kinetics is best fitted by the pseudo-second-order kinetic model.


2013 ◽  
Vol 726-731 ◽  
pp. 1922-1925 ◽  
Author(s):  
Lian Ai ◽  
Xue Gang Luo ◽  
Xiao Yan Lin ◽  
Si Zhao Zhang

The sorptive potential of sunflower straw (≤125 μm) for Sr2+ from aqueous solution was evaluated. Batch adsorption experiments were carried out as a function of solution pH, adsorbent dosage, Sr2+ concentration and contact time. FT-IR spectra and SEM of sunflower straw were employed to explore the functional groups available for the binding of Sr2+ and morphology of the adsorbent. Maximum uptake capacity of sunflower straw was 17.48 mg/g occurred at around pH 3-7. The adsorption equilibrium can be achieved within 5 min and kinetic data were fitted well to pseudo-second-order model. The Langmuir and Freundlich models were applied to describe isotherm sorption data. The Langmuir model gave an acceptable fit than Freundlich model.


2020 ◽  
Vol 2020 ◽  
pp. 1-9 ◽  
Author(s):  
Ilyasse Loulidi ◽  
Fatima Boukhlifi ◽  
Mbarka Ouchabi ◽  
Abdelouahed Amar ◽  
Maria Jabri ◽  
...  

Agricultural waste can be exploited for the adsorption of dyes, due to their low cost, availability, cost-effectiveness, and efficiency. In this study, we were interested in the elimination of crystal violet dye, from aqueous solutions, by adsorption on almond shell-based material, as a low-cost and ecofriendly adsorbent. The almond shells were first analyzed by Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction; then, the influence of adsorbent dose, initial dye concentration time, and pH were studied to assess adsorption capacity under optimal experimental conditions. Experimental results indicate that almond shell adsorbent removes about 83% of the dye from the solutions at room temperature and in batch mode; the kinetic study showed that the equilibrium time is about 90 min, and the model of pseudo-second order could very well describe adsorption kinetics. The modulation of adsorption isotherms showed that retention follows the Langmuir model. The thermodynamic study has shown that the adsorption is endothermic (ΔH° > 0) and spontaneous (ΔG° < 0).


Coatings ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 508
Author(s):  
Mohamed Abatal ◽  
M. T. Olguin ◽  
Ioannis Anastopoulos ◽  
Dimitrios A. Giannakoudakis ◽  
Eder Claudio Lima ◽  
...  

In this work, biomass obtained from seeds (S-MO) and leaves (L-MO) of the Moringa oleifera plant were used as low-cost biosorbents to remove the Pb(II), Cd(II), Co(II), and Ni(II) from aqueous solutions. The biosorption of the heavy metal ions was done using the batch technique. The effects of contact time (30–1440 min), biosorbent dosage (10–50 g/L) (0.1–0.5 g), and initial concentration of metals (10–500 mg/L) on the sorption capacity of metal ions were investigated. The S-MO and L-MO samples’ characterization was performed using pHpzc, X-ray Diffraction (XRD), and Fourier Transform Infrared Spectroscopy (FTIR). It was found that the pHpzc was notably different between the seeds and leave-derived biosorbents. The removal process’s experimental kinetic data for both S-MO and L-MO were best described by the pseudo-second-order model for all metal ions, with R2 above 0.997 in all cases. Langmuir and Freundlich’s models were also used to analyze the isotherms parameters. Based on the Langmuir model, the maximum sorption capacities (Qm) for L-MO were found as follows: L-MO-Pb > L-MO-Cd > L-MO-Co ≥ L-MO-Ni, and for S-MO, the values of Qm values presented the following order: S-MO-Pb > S-MO-Co > S-MO-Cd > S-MO-Ni.


Molekul ◽  
2021 ◽  
Vol 16 (1) ◽  
pp. 28
Author(s):  
Mohammad Jihad Madiabu ◽  
Joko Untung ◽  
Imas Solihat ◽  
Andi Muhammad Ichzan

The research aims to investigate feasibility eggshells as potential adsorbent to remove copper(II) ions from aqueous solution. Eggshells powder was characterized using X-ray diffraction, scanning electron microscopy, and Fourier transform infrared spectroscopy. Effect of copper(II) initial concentration, adsorbent dosage, and contact time have conducted. The optimum adsorption condition obtained when 0.7 g eggshells applied to 50 mg/L copper(II) solution for 50 minutes. The maximum percentage of copper(II) removal was exceeded more than 85%. Langmuir and Freundlich isotherm model were applied to describe the equilibrium adsorption. Copper(II) kinetics sorption process was fitted to pseudo-second order model with a rate constant equal to 0.516 g/mg.min. The results clearly exhibit that eggshells powder can be effectively used to remove copper(II) ions from aqueous solutions.


2021 ◽  
Vol 12 (6) ◽  
pp. 7845-7862

Water contamination caused by the presence of synthetic dye is one of the world's major environmental concerns. This work aims to explore the potential application of non-carbonized phosphoric acid-treated Balanites aegyptiaca "heglig" seed husks powder (BASHP) as a bio-sorbent for methylene blue (MB) removal from water bodies. BASHP was characterized using Fourier transform infrared spectroscopy (FTIR). The characteristics of BASHP, such as the iodine number, point of zero charges, solubility, and specific surface area (SMB) were also estimated. The biosorption of MB onto the BASHP surface was studied in batch mode under various conditions (contact time, shaking speed, solution temperature, initial solution pH, ionic strength, initial dye concentration, and biosorbent dosage). The adsorption kinetics and isotherm were better described by pseudo-second-order and Langmuir models, respectively. More than 97% of MB was removed, and the maximum biosorbed amount of MB (qmax) was 72.99 mg/g. Thermodynamics findings revealed that the proposed biosorption is an endothermic and spontaneous process. These findings showed that BASHP is a potentially eco-friendly, easily available, and low-cost material for removing hazardous dyes (e.g., methylene blue) from an aquatic environment, as well as a promising method for reducing agricultural solid waste (e.g., seed husks).


2021 ◽  
Vol 11 (7) ◽  
pp. 3125
Author(s):  
Candelaria Tejada-Tovar ◽  
Angel Villabona-Ortíz ◽  
Rodrigo Ortega-Toro ◽  
Humberto Mancilla-Bonilla ◽  
Fran Espinoza-León

The raw sawdust of Eucalyptusglobulus Labill was studied as an alternative of residual biomaterial for the adsorption of lead (II) in wastewater, evaluating the effect of pH (3, 4, 5, and 6) in a batch system. From the characterization of the biomaterial, it was found that the biomass has a low ash content, and from the scanning electron microscopy (SEM) microphotographs that it presents a porous morphology with diverse texture and presence of fiber fragments, which describe the heterogeneity of the material. The Fourier transform infrared (FTIR) spectrum showed the presence of functional groups of NHR, OH, COOH, and hydrocarbons, which are part of the structure of lignin, cellulose, hemicellulose, and pectin. From the adsorption experiments, it was obtained that the optimal value of pH 6, reaching a removal percentage of 96% and an adsorption capacity of 4.80 mg/g. The model that better adjusted the kinetics results was the pseudo-second-order model and the Langmuir and Freundlich isothermal models described the adsorption equilibrium; it was found that in the system prevails chemisorption, supported in ion exchange by Pb (II) and the biomass’ functional groups. From the results, eucalyptus sawdust is suggested as a low-cost adsorbent for Pb (II) bioadsorption present in solution.


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