Biosorption of As(V) from aqueous solutions by living cells of Bacillus cereus

2012 ◽  
Vol 66 (8) ◽  
pp. 1699-1707 ◽  
Author(s):  
A. K. Giri ◽  
R. K. Patel ◽  
P. C. Mishra

In this work, the biosorption of As(V) from aqueous solutions by living cells of Bacillus cereus has been reported. The batch biosorption experiments were conducted with respect to biosorbent dosage 0.5 to 15 g/L, pH 2 to 9, contact time 5 to 90 min, initial concentration 1 to 10 mg/L and temperature 10 to 40 °C. The maximum biosorption capacity of B. cereus for As(V) was found to be 30.04 at pH 7.0, at optimum conditions of contact time of 30 min, biomass dosage of 6 g/L, and temperature of 30 ± 2 °C. Biosorption data were fitted to linearly transformed Langmuir isotherms with R2 (correlation coefficient) >0.99. Bacillus cereus cell surface was characterized using AFM and FTIR. The metal ions were desorbed from B. cereus using both 1 M HCl and 1 M HNO3. The pseudo-second-order model was successfully applied to predict the rate constant of biosorption.

2011 ◽  
Vol 230-232 ◽  
pp. 1110-1113
Author(s):  
Yan Li Mao ◽  
Xiao Yan Ding ◽  
Hui Li Zhu ◽  
Fang Xia

The study described the sorption of Cd(II) by a novel extracellular biopolymer (B-11) produced from Bacillus cereus B-11. The effect of experimental parameters such as pH, initial concentration and contact time, sorbent dosage on the sorption was studied. The langmuir isotherm better fitted the sorption data, the maximum adsorption capacity was 80.64 mg.g-1. The kinetic rates were best fitted to the pseudo-second-order model. It was concluded that the prepared B-11 can be used as an effective and environmentally friendly biosorbent for the removal of Cd(II) ions from aqueous solution.


2013 ◽  
Vol 684 ◽  
pp. 194-197
Author(s):  
Yi Ke Li ◽  
Bing Lu Zhao ◽  
Wei Xiao ◽  
Run Ping Han ◽  
Yan Qiang Li

The effect of contact time and the determination of the kinetic parameters of adsorption of methyl orange (MO) from aqueous solution onto Iron-Oxide-Coated-Zeolite (IOCZ) powder are important in understanding the adsorption mechanism. The effect of contact time on adsorption quantity was studied at different initial concentration and temperature, respectively. The pseudo-second-order model was adopted to fit the experimental data using non-linear regressive analysis and it was used to predict the adsorption behavior. The results showed that the process of adsorption MO was endothermic and chemisorption. The pore diffusion was not significant.


2012 ◽  
Vol 9 (3) ◽  
pp. 1266-1275 ◽  
Author(s):  
J.Raffiea Baseri ◽  
P.N. Palanisamy ◽  
P. Sivakumar

In this research, Polyaniline coated sawdust (Polyaniline nano composite) was synthesized via direct chemical polymerization and used as an adsorbent for the removal of acid dye (Acid Violet 49) from aqueous solutions. The effect of some important parameters such as pH, initial concentration of dye, contact time and temperature on the removal efficiency was investigated in batch adsorption system. The adsorption capacity of PAC was high (96.84 %) at a pH of 3-4. The experimental data fitted well for pseudo second order model. Langmuir model is more appropriate to explain the nature of adsorption with high correlation coefficient. The Energy of activation from arrehenius plot suggested that the adsorption of AV49 onto PAC involves physisorption mechanism.


2018 ◽  
Vol 43 (6) ◽  
pp. 623-631 ◽  
Author(s):  
Reza Mahini ◽  
Hossein Esmaeili ◽  
Rauf Foroutan

Abstract Objective The presence of dyes in the water is toxic and harmful to human body so, it must be removed from the water. In the present study, the removal of methyl violet (MV) from aqueous solutions using brown algae “Padina sanctae-crucis” was investigated. Materials and methods The rate of adsorption was investigated under various parameters such as contact time (5–200), pH (2–11), dye concentration (10–60 mg/L), amount of adsorbent (0.25–5 g/L) and temperature (25–45°C). Results The maximum adsorption was achieved in 10 mg/L, pH=8 and adsorbent dose 2 g/L and 80 min contact time for removal of MV from aqueous solutions. Kinetic studies showed that the pseudo second-order model describes adsorbent kinetic behavior better. Besides, experimental data have been modeled using Langmuir and Freundlich isotherms and the results showed that both models are proper to describe adsorption isotherm behavior. In addition, the equilibrium study shows that the adsorption was physical and favorable. Moreover, a thermodynamic study revealed that the adsorption process is exothermic and spontaneously in nature. Furthermore, Maximum adsorption capacity using adsorbent was 10.02 mg/g. Conclusions It could be concluded that the P. sanctae-crucis biomass is a good adsorbent for removing MV dyes from aqueous solutions.


2016 ◽  
Vol 73 (9) ◽  
pp. 2132-2142 ◽  
Author(s):  
F. Ferrarini ◽  
L. R. Bonetto ◽  
Janaina S. Crespo ◽  
M. Giovanela

Adsorption has been considered as one of the most effective methods to remove dyes from aqueous solutions due to its ease of operation, high efficiency and wide adaptability. In view of all these aspects, this study aimed to evaluate the adsorption capacity of a halloysite-magnetite-based composite in the removal of Congo red dye from aqueous solutions. The effects of stirring rate, pH, initial dye concentration and contact time were investigated. The results revealed that the adsorption kinetics followed the pseudo-second-order model, and equilibrium was well represented by the Brunauer–Emmett–Teller isotherm. The thermodynamic data showed that dye adsorption onto the composite was spontaneous and endothermic and occurred by physisorption. Finally, the composite could also be regenerated at least four times by calcination and was shown to be a promising adsorbent for the removal of this dye.


2011 ◽  
Vol 63 (7) ◽  
pp. 1389-1395 ◽  
Author(s):  
S. Aber ◽  
D. Salari ◽  
B. Ayoubi Feiz

Batch sorption studies using almond shell as an sorbent for the removal of Cu (II) from aqueous solutions, showed that copper removal decreased from 74.9% to 45.6% with increasing its concentration from 10 to 70 ppm. The removal increased with increasing sorbent dose and pH, respectively. Copper removal was obtained equal to 63.7%, 69.6% and 58.6% at 26˚C, 40˚C and 55˚C. The sorption of Cu (II) on almond shell was also optimized by Taguchi method. The optimized conditions were the sorbent mass of 4 g, the ion initial concentration of 10 ppm, pH 7, the temperature of 40˚C and contact time equal to 60 min. The pH and initial Cu (II) concentration with respectively 32.75% and 31.20% contribution had more influence on the removal of Cu (II). The kinetic data fit pseudo-second-order model with correlation coefficients greater than 0.99 and rate constants in the range of 0.26–7.87 g mg−1 min−1.


2010 ◽  
Vol 178 ◽  
pp. 8-16
Author(s):  
Liang Dong Feng ◽  
Bo Qing Chen ◽  
Ying Ying Shi ◽  
Ying Wei Guo ◽  
Jing Huang ◽  
...  

1, 10-phenanthroline and triethylamine modified palygorskites were prepared by microwave irradiation, and characterized with FT-IR technique. The effects of contact time, adsorbent dosage, and pH value of the initial solution on the adsorption characters of Mn2+ were investigated. The adsorption of Mn2+ from aqueous solutions using 1, 10-phenanthroline or triethylamine modified palygorskites were investigated. Experiment results indicated that 1,10-phenanthroline and triethylamine molecules have been successfully grafted to palygorskite. The adsorption was rapid during the first 5 minuts and equilibrium were attained within 60 minutes in the initial concentration of Mn2+ of 50 and 100 mg•L-1, and fast adsorption in the first 10 minutes and slowly increased with the contact time due to the adsorption of palygorskite. The 1, 10-phenanthroline modified palygorskites had higher adsorption capacity than triethylamine modified palygorskites. Compared with natural palggorskites, the Mn2+ ions adsorption capacities of palggorskite modified by 1, 10-phenanthroline or triethylamine were significantly improved. There were less difference in the adsorption capacity between different dasages of 1, 10-phenanthroline modified palygorskites, but the adsorption capacity of Mn2+ adsorbed onto triethylamine modified palygorskites decreased with increasing the dosages. A Lagergren pseudo-second order model best described the kinetics of adsorption of Mn2+ onto the modified palygorskites.


Author(s):  
C. Obi ◽  
N. C. Ngobiri ◽  
L. C. Agbaka ◽  
M. U. Ibezim-Ezeani

The study focused on the investigation of the effectiveness of the pericarp of monkey kola (Cola lepidota) biomass (CLPB) in the removal of toluene from aqueous system. X-Ray Diffraction (XRD), Fourier Transform Infrared (FTIR), Scanning Electron Microscopy (SEM) and phytochemical screening methods were used for characterizing the biosorbent. The effects of contact time, pH, and concentration on biosorption process were studied. The phytochemical screening showed the presence of alkaloids, flavonoids, tannins, carbohydrate, saponins and steroids. Carboxylic, alkene and alcohol groups were found to be the principal functional groups. The highest percentage removal was 99.63% at toluene initial concentration of 40 mg/L and 98.30% at pH 8. The contact time 30 minutes gave better removal efficiency of 99.89%. Among the biosorption isotherm models tested (Langmuir, Freundlich, Dubinin Radushkevich and Temkin, respectively), the Langmuir model equation gave a better fit of the equilibrium data with a correlation coefficient (R2) of 0.99. The equilibrium data was tested with pseudo-first order and pseudo-second order models and pseudo-second order model (R² = 0.99) fitted more than the pseudo-first order model (R² = 0.85). This study has revealed that Cola lepidota is a potential biosorbent for the removal of toluene from aqueous medium under the operating conditions of contact time of 30 minutes, pH of 8 and initial concentration of 40 mg/g.


Author(s):  
Alica Pastierová ◽  
Maroš Sirotiak

Abstract This paper presents a study into dynamic behaviour of the methylene blue adsorption (MB) on activated carbon. Effect of four parameters were studied: effect of the adsorbent dosage, effect of contact time, effect of pH, and effect of the initial concentration of methylene blue. The adsorption kinetic data were modelled using the pseudo-first and pseudo-second orders. Results show that, based on the experimental data, the pseudo-second order could be considered satisfactory. Thermodynamic parameters proved that adsorption of dye was spontaneous owing to increase in temperature and endothermic nature. Taguchi method was applied to determine the optimum conditions for removal of methylene blue by activated carbon. The optimum conditions were found to be pH = 7, contact time 60 min, initial concentration of MB 4 mg/L.


2019 ◽  
Vol 35 (4) ◽  
pp. 1384-1391
Author(s):  
Abdur-Rahim Adebisi ◽  
Giwa Khadijat Ayanpeju ◽  
Abdulsalam Francois Wewers ◽  
Mary Adelaide Oladipo

The study investigates the effectiveness and mechanism of the adsorption of malachite green from single and mixed dyes aqueous solutions by an adsorbent prepared from acid-treated Parkia biglobosa sawdust. The adsorbent was characterized using different techniques, and the adsorption was conducted in single, binary, ternary and quaternary dye systems under different experimental conditions. Experimental results were subjected to different isotherm and kinetics models. The adsorption process was endothermic and thermodynamically feasible with the removal efficiency increasing with increase in adsorbent dosage, solution working pH, initial dye concentration and contact time. The rate of sorption of the dye was fast; it attained equilibrium within 180 minutes in both the single and mixed solute systems. Pseudo-second order model gives the best kinetics fit (R2 = 0.998). The adsorption isotherm in all solute systems have best fits for the Temkin model (R2 > 0.96).


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