Removal of dyes from aqueous solutions using activated carbon prepared from rice husk residue

2015 ◽  
Vol 73 (5) ◽  
pp. 1122-1128 ◽  
Author(s):  
Yaxin Li ◽  
Xian Zhang ◽  
Ruiguang Yang ◽  
Guiying Li ◽  
Changwei Hu

The treatment of dye wastewater by activated carbon (AC) prepared from rice husk residue wastes was studied. Batch adsorption studies were conducted to investigate the effects of contact time, initial concentration (50–450 mg/L), pH (3–11) and temperature (30–70 °C) on the removal of methylene blue (MB), neutral red, and methyl orange. Kinetic investigation revealed that the adsorption of dyes followed pseudo-second-order kinetics. The results suggested that AC was effective to remove dyes, especially MB, from aqueous solutions. Desorption studies found that chemisorption by the adsorbent might be the major mode of dye removal. Fourier transform infrared results suggested that dye molecules were likely to combine with the O–H and P=OOH groups of AC.

Heliyon ◽  
2021 ◽  
pp. e07191
Author(s):  
Fateme Barjasteh-Askari ◽  
Mojtaba Davoudi ◽  
Maryam Dolatabadi ◽  
Saeid Ahmadzadeh

2012 ◽  
Vol 14 (4) ◽  
pp. 88-94 ◽  
Author(s):  
R.P. Suresh Jeyakumar ◽  
V. Chandrasekaran

Abstract In this work, the efficiency of Ulva fasciata sp. activated carbons (CCUC, SCUC and SSUC) and commercially activated carbon (CAC) were studied for the removal of Cu (II) ions from synthetic wastewater. Batch adsorption experiments were carried out as a function of pH, contact time, initial copper concentration and adsorbent dose. The percentage adsorption of copper by CCUC, SSUC, SCUC and CAC are 88.47%, 97.53%, 95.78% and 77.42% respectively. Adsorption data were fitted with the Langmuir, Freundlich and Temkin models. Two kinetic models pseudo first order and the pseudo second order were selected to interpret the adsorption data.


2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Lingjie Liu ◽  
Min Ji ◽  
Fen Wang

Coconut granular activated carbon (CGAC) was modified by impregnating with ZnCl2solution to remove nitrate from aqueous solutions. Sorption isotherm and kinetic studies were carried out in a series of batch experiments. Nitrate adsorption of both ZnCl2-modified CGAC and CGAC fitted the Langmuir and Freundlich models. Batch adsorption isotherms indicated that the maximum adsorption capacities of ZnCl2-modified CGAC and CGAC were calculated as 14.01 mgN·g−1and 0.28 mgN·g−1, respectively. The kinetic data obtained from batch experiments were well described by pseudo-second-order model. The column study was used to analyze the dynamic adsorption process. The highest bed adsorption capacity of 1.76 mgN·g−1was obtained by 50 mgN·L−1inlet nitrate concentration, 20 g adsorbents, and 10 ml·min−1flow rate. The dynamic adsorption data were fitted well to the Thomas and Yoon–Nelson models with coefficients of correlationR2 > 0.834 at different conditions. Surface characteristics and pore structures of CGAC and ZnCl2-modified CGAC were performed by SEM and EDAX and BET and indicated that ZnCl2had adhered to the surface of GAC after modified. Zeta potential, Raman spectra, and FTIR suggested the electrostatic attraction between the nitrate ions and positive charge. The results revealed that the mechanism of adsorption nitrate mainly depended on electrostatic attraction almost without any chemical interactions.


Polymers ◽  
2021 ◽  
Vol 13 (22) ◽  
pp. 3890
Author(s):  
Chenlu Jiao ◽  
Die Liu ◽  
Nana Wei ◽  
Jiannan Gao ◽  
Fan Fu ◽  
...  

Porous sustainable cellulose/gelatin/sepiolite gel beads were fabricated via an efficient ‘hydrophilic assembly–floating droplet’ two-step method to remove Congo red (CR) from wastewater. The beads comprised microcrystalline cellulose and gelatin, forming a dual network framework, and sepiolite, which acted as a functional component to reinforce the network. The as-prepared gel beads were characterized using FTIR, SEM, XRD, and TGA, with the results indicating a highly porous structure that was also thermally stable. A batch adsorption experiment for CR was performed and evaluated as a function of pH, sepiolite addition, contact time, temperature, and initial concentration. The kinetics and isotherm data obtained were in agreement with the pseudo-second-order kinetic model and the Langmuir isotherm, with a maximum monolayer capacity of 279.3 mg·g−1 for CR at 303 K. Moreover, thermodynamic analysis demonstrated the spontaneous and endothermic nature of the dye uptake. Importantly, even when subjected to five regeneration cycles, the gel beads retained 87% of their original adsorption value, suggesting their suitability as an efficient and reusable material for dye wastewater treatments.


2018 ◽  
Vol 3 (1) ◽  
pp. 4 ◽  
Author(s):  
Liudmyla Soldatkina ◽  
Marianna Zavrichko

Corn stalks (CS) were modified by a cationic surfactant, cetylpyridinium bromide (CPB), and used as an adsorbent (CS-CP) to remove anionic dyes [Acid Red (AR) and Acid Orange (AO)] from aqueous solutions. The FTIR analysis and the obtained calculations based on the determination of the adsorption capacity of CS towards CPB confirmed that the cationic surfactant had been adsorbed on the surface of corn stalks. Adsorption of the anionic dyes on modified corn stalks was investigated in a series of batch adsorption experiments at 303–328 K. The adsorption data were analyzed using Langmuir, Freundlich, and Temkin models. The Langmuir model was found to be more suitable for the experimental data of the anionic dyes on CS-CP than other adsorption models. Kinetic studies revealed that the pseudo-second order model showed the best fit to the experimental data. The thermodynamic parameters indicated that the adsorption process was spontaneous and exothermic. Mechanisms involving ion exchange and chemisorption might be responsible for the uptake of the anionic dyes on CS-CP. Obtained results imply that CS-CP could be applied as an effective adsorbent to remove anionic dyes from aqueous solutions.


2012 ◽  
Vol 60 (2) ◽  
pp. 185-189 ◽  
Author(s):  
Mohammad Arifur Rahman ◽  
S. M. Ruhul Amin ◽  
A. M. Shafiqul Alam

The possible utilization of rice husk activated carbon as an adsorbent for the removal of methylene blue dye from aqueous solutions has been investigated. In this study, activated carbons, prepared from low-cost rice husk by sulfuric acid and zinc chloride activation, were used as the adsorbent for the removal of methylene blue, a basic dye, from aqueous solutions. Effects of various experimental parameters, such as adsorbent dosage and particle size, initial dye concentration, pH and flow rate were investigated in column process. The maximum uptakes of methylene blue by activated rice husk carbon at optimized conditions (particle sizes: 140 ?m; Flow rate: 1.4 mL/min; pH: 10.0; initial volume of methylene blue: 50 mL and initial concentration of methylene blue: 4.0 mg/L etc.) were found to 97.15%. The results indicate that activated carbon of rice husk could be employed as low-cost alternatives to commercial activated carbon in waste water treatment for the removal of basic dyes. This low cost and effective removal method may provide a promising solution for the removal of crystal violet dye from wastewater.DOI: http://dx.doi.org/10.3329/dujs.v60i2.11491 Dhaka Univ. J. Sci. 60(2): 185-189, 2012 (July)


2011 ◽  
Vol 354-355 ◽  
pp. 33-36
Author(s):  
Jian Yun Li ◽  
Quan Xian Hua ◽  
Jun Ling Niu ◽  
Jian Wei Tang ◽  
Ke Xu

The adsorption of copper in aqueous solutions by steel slag was studied in batch adsorption experiments. The adsorption equilibrium data fitted best with Langmuir and Freundlich equations. The adsorption was preferential type. A comparison of the kinetics models on the apparent adsorption rate showed that the adsorption system was best described by the pseudo-second-order kinetics. The adsorption rate was controlled by both liquid film diffusion and intraparticle dispersion.


2018 ◽  
Vol 5 (5) ◽  
pp. 172382 ◽  
Author(s):  
Wei Guo ◽  
Shujuan Wang ◽  
Yunkai Wang ◽  
Shaoyong Lu ◽  
Yue Gao

A magnetically modified rice husk biochar (MBC) was successfully prepared by a hydrothermal method from original biochar (BC) and subsequently used to remove phenanthrene (PHE) from aqueous solutions. The porosity, specific surface area and hydrophobicity of BC were significantly improved (approx. two times) after magnetic modification. The adsorption data fitted well to pseudo-second-order kinetic and Langmuir models. Compared with BC, MBC had a faster adsorption rate and higher adsorption capacity of PHE. The adsorption equilibrium for PHE on MBC was achieved within 1.0 h. The maximum adsorption capacity of PHE on MBC was 97.6 mg g −1 based on the analysis of the Sips model, which was significantly higher than that of other sources of BCs. The adsorption mechanism of the two BCs was mainly attributed to the action of surface functional groups and π–π-conjugated reactions. The adsorption of PHE on MBC mainly occurred in the functional groups of C–O and Fe 3 O 4 , but that on BC was mainly in the functional groups of –OH, N–H, C=C and C–O.


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