scholarly journals Utilization of anaerobic granular sludge for chromium (VI) removal from wastewater: optimization by response surface methodology

2017 ◽  
Vol 76 (5) ◽  
pp. 1112-1123
Author(s):  
Yifan Hu ◽  
Changzhu Yang ◽  
Jinfeng Dan ◽  
Wenhong Pu ◽  
Jiakuan Yang
Keyword(s):  
Photoelectron Spectroscopy ◽  
Freundlich Isotherm ◽  
Granular Sludge ◽  
Polynomial Equation ◽  
Anaerobic Granular Sludge ◽  
Order Kinetic ◽  
Chromium Vi ◽  
Biosorption Process ◽  
Initial Ph ◽  
The Impact

In this study, anaerobic granular sludge (AGS) was used as a novel adsorbent for hexavalent chromium (Cr (VI)) removal from aqueous solutions. Factor experiments were conducted to find out the effects of different variables on the biosorption process. Among these terms, the impact of three main independent variables (contact time, initial pH and AGS dosage) on the removal efficiency of Cr (VI) was modeled using a well-fitting polynomial equation (R2 = 0.9044), by conducting 20 batch experiments designed by a central composite. The experimental isotherm data were successfully described by the Freundlich isotherm and the pseudo-second-order kinetic model was more suitable for explaining the kinetics process of adsorption. The AGS can be disposed using 0.1 M NaOH with 96.4% desorption efficiency. The results of the analyses (X-ray photoelectron spectroscopy and Fourier transformed infrared spectroscopy) suggested that Cr (VI) adsorption most likely involved electrostatic adsorption, redox reaction and complexation.

Biosorption of Cu2+ by Anaerobic Granular Sludge

2014 ◽  
Vol 945-949 ◽  
pp. 3483-3488
Author(s):  
Bai Ren Yang ◽  
Dong Xue Liu ◽  
Xian Niu ◽  
Cheng Ding
Keyword(s):  
Freundlich Isotherm ◽  
Granular Sludge ◽  
Solution Temperature ◽  
Anaerobic Granular Sludge ◽  
Order Kinetic ◽  
Desorption Process ◽  
Biosorption Process ◽  
Order Kinetic Model ◽  
Pseudo Second Order ◽  
Isotherm Equations

In order to investigate the biosorption of Cu2+ by anaerobic granular sludge, the effect of equilibrium time, pH, sludge dosage, biosorption kinetics, biosorption thermodynamics and biosorption isotherms had been studied. Results showed that pseudo second-order kinetic model was useful to describe the biosorption process of Cu2+. Both Langmuir and Freundlich isotherm equations could well describe the desorption process at 15-55 °C. Thermodynamic studies showed that the biosorption process was spontaneous and endothermic in nature. When the solution temperature maintained at 35 °C, pH of 6~7, a good biosorption process could be obtained.

Biosorption of Cr(VI) from Aqueous Solution by Aspergillus Niger

2011 ◽  
Vol 236-238 ◽  
pp. 155-158
Author(s):  
Li Fang Zhang ◽  
Shu Juan Dai ◽  
Ying Ying Chen
Keyword(s):  
Aqueous Solution ◽  
Aspergillus Niger ◽  
Contact Time ◽  
Correlation Coefficients ◽  
Second Order ◽  
Order Kinetic ◽  
Chromium Vi ◽  
Biosorption Process ◽  
Initial Ph ◽  
Pseudo Second Order

In this study, Biosorption of hexavalent chromium ions from aqueous solution by using biomass ofAspergillus nigerwas investigated. Different parameters such as initial pH, biosorbent amount, contact time and temperature were explored. The biosorption of Cr (VI) ions was highly pH dependent and the optimum pH for biosorption of Cr (VI) ions was found to be 2.0. Biosorption capacity of Cr (VI) ions decreased with increased biosorbent dosage. The biosorption equilibrium was established in about 120min of contact time. Equilibrium uptake of Cr (VI) ions onto biomass increased from 12.57 mg/g at 20°C to 19.48 mg/g at 40 °C for 20mg/L Cr (VI) ions concentration. The biosorption process followed the pseudo-second order kinetic model and the correlation coefficients from the pseudo-second order model were all higher than 0.997 in all studied temperatures. These results suggest that the biomass ofAspergillus nigeris a promising biosorbent for removal of chromium (VI) ions from the wastewater.

scholarly journals Biosorption of zinc from aqueous solution by cyanobacterium Fischerella ambigua ISC67: optimization, kinetic, isotherm and thermodynamic studies

2018 ◽  
Vol 78 (7) ◽  
pp. 1525-1534 ◽  
Author(s):  
Moein Safari ◽  
Salman Ahmady-Asbchin
Keyword(s):  
Aqueous Solution ◽  
Contact Time ◽  
Bacterial Biomass ◽  
Freundlich Isotherm ◽  
Ion Concentration ◽  
Infrared Analysis ◽  
Order Kinetic ◽  
Biosorption Process ◽  
Initial Ph ◽  
Effects Of Ph

Abstract In this present study, biosorption of Zn(II) from aqueous solution by cyanobacterium Fischerella ambigua was investigated in batch experiments. The effects of pH, bacterial dosage, initial Zn(II) concentration, contact time and temperature were studied. Removal process was influenced significantly by the variation of pH, biosorbent concentration, initial Zn(II) ion concentration, temperature and contact time. Optimum biosorption conditions were found to be initial pH of 5, bacterial dosage of 0.2 g/l and initial Zn(II) ion concentration of 175 mg/l at room temperature and contact time of 90 min. The maximum uptake capacity of F. ambigua for Zn(II) ions was found to be 98.03 mg/g at optimum conditions. The correlation coefficient for the second-order kinetic model was 0.995. The Freundlich isotherm model showed better fit to the equilibrium of the system, compared with the Langmuir model. Fourier transform infrared analysis of bacterial biomass revealed the presence of carboxyl, hydroxyl, sulfite and amino groups, which are likely responsible for the biosorption of Zn(II). The negative values of Gibbs free energy, ΔG°, confirm the spontaneous nature of the biosorption process. Finally, F. ambigua adsorption capacity was compared with other biosorbents. Results showed that F. ambigua was an efficient biosorbent in the removal of Zn(II) ions from an aqueous solution.

Adsorption of Chromium (VI) from Aqueous Solution by Agricultural Waste Derived Activated Carbon

2013 ◽  
Vol 726-731 ◽  
pp. 2100-2106 ◽  
Author(s):  
Hua Zhang ◽  
Xue Hong Zhang ◽  
Yi Nian Zhu ◽  
Shou Rui Yuan
Keyword(s):  
Aqueous Solution ◽  
Activated Carbon ◽  
Agricultural Waste ◽  
Order Kinetic ◽  
Chromium Vi ◽  
Initial Ph ◽  
Order Kinetic Model ◽  
Grapefruit Peel ◽  
Pseudo Second Order ◽  
C 30

Activated carbon prepared from grapefruit peel, an agricultural solid waste by-product, has been used for the adsorption of Cr(VI) from aqueous solution. The effects of adsorbent dosage, pH and temperature on adsorption of Cr(VI) were investigated. The maximum adsorption yield was obtained at the initial pH of 3. The dynamical data fit very well with the pseudo-second-order kinetic model and the calculated adsorption capacities (23.98, 24.33 and 24.81 mg/g) were in good agreement with experiment results at 20°C, 30°C and 40 °C for the 100 mg/L Cr(VI) solution. The Freundlich model (R2 values were 0.9198-0.9871) fitted adsorption data better than the Langmuir model. The calculated parameters confirmed the favorable adsorption of Cr(VI) on the activated carbon prepared from grapefruit peel.

scholarly journals Removal of Chromium(VI) by Chitosan Beads Modified with Sodium Dodecyl Sulfate (SDS)

2020 ◽  
Vol 10 (14) ◽  
pp. 4745
Author(s):  
Xiaoyu Du ◽  
Chihiro Kishima ◽  
Haixin Zhang ◽  
Naoto Miyamoto ◽  
Naoki Kano
Keyword(s):  
Sodium Dodecyl Sulfate ◽  
Adsorption Capacity ◽  
Photoelectron Spectroscopy ◽  
Sodium Dodecyl ◽  
Isotherm Models ◽  
Order Kinetic ◽  
Chitosan Beads ◽  
X Ray ◽  
Chromium Vi ◽  
Dodecyl Sulfate

In this study, chitosan beads modified with sodium dodecyl sulfate (SDS) were successfully synthesized and employed for the removal of chromium(VI) (Cr(VI)). The adsorption performance of the adsorbent (SDS-chitosan beads) was examined by batch experiments. The partition coefficient (PC) as well as the adsorption capacity were evaluated to assess the true performance of the adsorbent in this work. The adsorbent (SDS-chitosan beads) showed a maximum Cr(VI) adsorption capacity of 3.23 mg·g−1 and PC of 9.5 mg·g−1·mM−1 for Cr(VI). The prepared adsorbent was characterized by different techniques such as scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS), X-ray photoelectron spectroscopy (XPS) and Fourier transform-infrared spectroscopy (FT-IR). We used inductively coupled plasma mass spectrometry (ICP-MS) for the determination of Cr(VI) in solution. The experimental data could be well-fitted by pseudo-second-order kinetic and Langmuir isotherm models. The thermodynamic studies indicated that the adsorption process was favorable under the higher temperature condition. The SDS-modified chitosan beads synthesized in this work represent a promising adsorbent for removing Cr(VI).

Biosorption of hexavalent chromium from aqueous solution by polyethyleneimine-modified ultrasonic-assisted acid hydrochar from Sargassum horneri

2020 ◽  
Vol 81 (6) ◽  
pp. 1114-1129 ◽  
Author(s):  
Jun Wang ◽  
Qinglong Xie ◽  
Ao Li ◽  
Xuejun Liu ◽  
Fengwen Yu ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Photoelectron Spectroscopy ◽  
Batch Adsorption ◽  
Crosslinking Reaction ◽  
Order Kinetic ◽  
Adsorption Capacities ◽  
Initial Ph ◽  
Ultrasonic Assisted ◽  
Order Kinetic Model ◽  
Pseudo Second Order

Abstract In this study, an efficient route to synthesizing polyethyleneimine-modified ultrasonic-assisted acid hydrochar (PEI-USAH) is developed and reported. Ultrasonic irradiation technique was used as surface modification method to shorten the crosslinking reaction for hydrochar and polyethyleneimine (PEI). The PEI-USAH showed an excellent adsorption capacity for Cr(VI) from aqueous solution. The physicochemical properties of this PEI-modified adsorbent were comparatively characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, Brunauer–Emmett–Teller analysis and CNHS analysis. The effects of contact time, initial pH, and biosorbent dose on adsorption capacities were investigated. The batch adsorption experiments showed that PEI-USAH possessed the maximum adsorption capacities of 94.38 mg/g and 330.84 mg/g for initial Cr(VI) concentration of 100 mg/L and 500 mg/L, respectively. Furthermore, this adsorption process could be fitted to Langmuir adsorption and described by the pseudo second order kinetic model. Based on the above findings, PEI-USAH could be used as a potential adsorbent for removal of Cr(VI) from wastewater.

Research on the Cr (VI) Absorption by Activated Sludge

2012 ◽  
Vol 229-231 ◽  
pp. 138-141
Author(s):  
Qiang Li ◽  
Sheng Han ◽  
Da Ke Hao ◽  
Jia Jia Wang ◽  
Yan Luo ◽  
...  
Keyword(s):  
Activated Sludge ◽  
High Efficiency ◽  
Removal Rate ◽  
Freundlich Isotherm ◽  
Irreversible Adsorption ◽  
Static Test ◽  
Reversible Adsorption ◽  
Biosorption Process ◽  
Initial Ph ◽  
Isotherm Adsorption

The adsorption performance of Cr (VI) on activated sludge and the effect of adsorption time, pH, temperature on the adsorption and desorption were studied. The initial pH is important for biosorption, and the optimum effect on Cr (VI) biosorption is acquired within initial pH of 0.5-1.0. Activated sludge has high efficiency of treating low concentration Cr (VI) wastewater. The removal rate of Cr (VI) could reach 99% when the total concentrations of Cr (VI) were 10 mg/L. The results of static test showed that the adsorption equilibrium was reached within 60 min. The biosorption process was fitted into Langmuir and Freundlich isotherm adsorption equations. It is presumed that the progress of biosorption was reversible adsorption and irreversible adsorption simultaneously, however the reversible adsorption was more important in the biosorption and the adsorption belongs to physics adsorption.

Equilibrium and Thermodynamic Studies on Biosorption of Malachite Green from Aqueous Solution by Fungal Biomass

2011 ◽  
Vol 148-149 ◽  
pp. 470-473
Author(s):  
Li Fang Zhang
Keyword(s):  
Aqueous Solution ◽  
Malachite Green ◽  
Fungal Biomass ◽  
Ph Value ◽  
Freundlich Isotherm ◽  
Isotherm Models ◽  
Thermodynamic Studies ◽  
Biosorption Process ◽  
Initial Ph ◽  
Equilibrium Data

The biosorption of Malachite Green from aqueous solution was investigated by using pretreated fungal biomass in a batch system. The effects of initial pH, NaCl concentration, initial dye concentration and temperature on dye biosorption were studied. The results showed that the pretreated fungal biomass exhibited higher dye removal at initial pH value of 5.0-6.0. The bosorption capacity was increased with the increasing temperature in studied temperature range. The Langmuir and Freundlich isotherm models were applied to experimental equilibrium data and the Langmuir model better described the equilibrium dye uptake than the Freundlich model. Thermodynamic studies revealed that the biosorption process was successful, spontaneous and endothermic in nature.

scholarly journals Adsorption Behaviour of Chromium(VI) onto Surface Modified Sugarcane Waste

2013 ◽  
Vol 28 (1-2) ◽  
pp. 113-122
Author(s):  
Kedar Nath Ghimire ◽  
Deepak Wagle ◽  
Suman Lal Shrestha
Keyword(s):  
Volume Ratio ◽  
Freundlich Isotherm ◽  
Batch Adsorption ◽  
Maximum Adsorption Capacity ◽  
Order Kinetic ◽  
Adsorption Method ◽  
Chromium Vi ◽  
Order Kinetic Model ◽  
Pseudo Second Order ◽  
Surface Modified

An effective chemically modified adsorbent based on sugarcane waste has been prepared by treating with concentrated sulphuric acid in 2:1weight/volume ratio. Thus prepared adsorbent has been found to be effective in the adsorption of chromium from aqueous medium. The efficacy of the adsorbent in the removal of chromium was evaluated by batch adsorption method. The effect of initial concentration, contact time and pH of the solution was investigated. The maximum adsorption capacity onto this adsorbent was found to be 195 mg/g at their optimal pH 1 at which unmodified bagasse has only 58 mg/g. The characterization of adsorbent was done by determining surface area and Boehm’s titration method. Freundlich isotherm and pseudo-second order kinetic model gave better explanation of the adsorption process.

scholarly journals Efficient Removal of Copper Ion from Wastewater Using a Stable Chitosan Gel Material

Molecules ◽  
2019 ◽  
Vol 24 (23) ◽  
pp. 4205 ◽  
Author(s):  
Yang ◽  
Chai ◽  
Zeng ◽  
Gao ◽  
Zhang ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Photoelectron Spectroscopy ◽  
Metal Ion ◽  
Physical Adsorption ◽  
Copper Ion ◽  
Freundlich Isotherm ◽  
Alkaline Media ◽  
Maximum Adsorption Capacity ◽  
Order Kinetic ◽  
Chitosan Gel

: 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.

Sign in / Sign up

Export Citation Format

Share Document