Effective adsorption of nickel (II) with Ulva lactuca dried biomass: isotherms, kinetics and mechanisms

2018 ◽  
Vol 78 (1) ◽  
pp. 156-164 ◽  
Author(s):  
Jianyou Long ◽  
Xiaona Huang ◽  
Xiaoli Fan ◽  
Yan Peng ◽  
Jianrong Xia

Abstract This study aimed to evaluate the Ni2+ ions adsorption capability of Ulva lactuca. The isotherms, kinetics and mechanisms for the adsorption of Ni2+ from aqueous solution by Ulva lactuca were also investigated. Influencing factors including initial pH, initial Ni2+ concentration, biomass, contact time were examined. The results indicate that the maximum Ni2+ adsorption capacity of 38.28 mg/g was obtained at pH 5, initial Ni2+ concentration 250 mg/L, biomass dosage 0.5 g/L and contact time 30 min. The adsorption can be well fitted with Langmuir isotherm, and the kinetics were well described by the pseudo-second-order model. The parameters of thermodynamics verified that Ni2+ adsorption on Ulva lactuca was a spontaneous and endothermic process. Analyses of FT-IR, SEM-EDS and XPS indicate that carboxyl and hydroxyl groups on the surface of biomass are involved in Ni2+ adsorption. The dried biomass of Ulva lactuca can be a cost-effective and eco-friendly adsorbent for the removal of Ni2+ from wastewater.

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.


2016 ◽  
Vol 75 (5) ◽  
pp. 1071-1083 ◽  
Author(s):  
Isha Vishan ◽  
Avishek Laha ◽  
Ajay Kalamdhad

The presence of heavy metals in the environment due to industrial activities is of serious concern because of their toxic behaviour towards humans and other forms of life. Biosorption of Pb(II) using dry bacterial biomass of Bacillus badius AK, previously isolated from water hyacinth compost, has been undertaken in batch system. The optimum conditions of biosorption were determined by investigating the initial pH, contact time, initial biomass dosage at constant temperature of 40 °C, initial metal concentration of 100 mg/L and rotational speed of 150 rpm. The optimum pH was found to be 5 and equilibrium contact time was 2.5 h. The maximum biosorption capacity of Pb(II) on Bacillus badius AK was 138.8 mg/g at an initial concentration of 100 mg/L. A kinetics study revealed that the adsorption process followed pseudo second order rate kinetics. The experimental data were fitted to the Langmuir isotherm. Characterization of the biomass indicated the presence of several functional groups. The results indicated that the bacterium Bacillus badius AK is efficient for the removal of Pb(II).


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.


2015 ◽  
Vol 73 (6) ◽  
pp. 1269-1278 ◽  
Author(s):  
Hejun Gao ◽  
Luanluan Zhang ◽  
Yunwen Liao

A novel adsorbent consisting of polyethyleneimine-modified multi-wall carbon nanotubes (PEI-MWCNTs) was synthesized by grafting PEI on the carboxyl MWCNTs. The surface properties of the PEI-MWCNTs were measured by scanning electron microscopy, thermogravimetric analysis, Fourier transform infrared, and zeta potential. The adsorption behavior of the PEI-MWCNTs was investigated using sunset yellow FCF as adsorbate. The effects of dosage of adsorbent, the initial pH of solution, contact time and temperature on the adsorption capacity were studied. Then, the kinetics and thermodynamics of the adsorption process were further investigated. Experimental results showed that the adsorption kinetics fitted a pseudo-second-order model and the adsorption isotherms agreed well with the Langmuir model. The adsorption process occurred very fast and the adsorption capacity of PEI-MWCNTs was much higher than that of many of the previously reported adsorbents. Additionally, the plausible adsorption mechanism was discussed.


2014 ◽  
Vol 1065-1069 ◽  
pp. 3123-3126
Author(s):  
Gang Chao Zhu ◽  
Jian Xin Shou ◽  
Jia Wei Qian ◽  
Hua Zheng Xin ◽  
Mu Qing Qiu

In this study, sawdust modified by cetyltimethyl ammonium bromide was applied to adsorb conge red in aqueous solutions. The characteristics of modified sawdust were characterized by Fourier transform infrared spectrum and scanning electron microscopy. The effect of factors, such as pH, contact time, temperature, dosage, and salt concentration, were investigated. The results revealed that the addition of modified sawdust can significantly increase the adsorption capacity of dye. The maximum adsorption capacity of dye on modified sawdust was 109 mg·g-1 at 328K. The adsorption processes were rapid within the first 30 min and reached equilibrium in about 150 min. The adsorption kinetics fitted well with pseudo-second-order model. The pH value of the solution had significant impact on the amount of adsorption. Adsorption isotherm fitted better with the Langmuir model and the adsorption was an endothermic process


2020 ◽  
Vol 16 (7) ◽  
pp. 880-892
Author(s):  
Şerife Parlayıcı ◽  
Kübra Tuna Sezer ◽  
Erol Pehlivan

Background: In this work, Cr (VI) adsorption on nano-ZrO2๏TiO2 impregnated orange wood sawdust (Zr๏Ti/OWS) and nano-ZrO2๏TiO2 impregnated peach stone shell (Zr๏Ti/PSS) was investigated by applying different adsorption parameters such as Cr (VI) concentrations, contact time, adsorbent dose, and pH for all adsorbents. Methods: The adsorbents were characterized by SEM and FT-IR. The equilibrium status was achieved after 120 min of contact time and optimum pH value around 2 were determined for Cr (VI) adsorption. Adsorption data in the equilibrium is well-assembled by the Langmuir model during the adsorption process. Results: Langmuir isotherm model showed a maximum adsorption value of OWS: 21.65 mg/g and Zr๏Ti/OWS: 27.25 mg/g. The same isotherm displayed a maximum adsorption value of PSS: 17.64 mg/g, and Zr๏Ti/PSS: 31.15 mg/g. Pseudo-second-order kinetic models (R2=0.99) were found to be the best models for describing the Cr (VI) adsorption reactions. Conclusıon: Thermodynamic parameters such as changes in ΔG°, ΔH°, and ΔS° have been estimated, and the process was found to be spontaneous.


Molecules ◽  
2021 ◽  
Vol 26 (5) ◽  
pp. 1437
Author(s):  
Chih Ming Ma ◽  
Bo-Yuan Yang ◽  
Gui-Bing Hong

Hydrogel beads based on the husk of agarwood fruit (HAF)/sodium alginate (SA), and based on the HAF/chitosan (CS) were developed for the removal of the dyes, crystal violet (CV) and reactive blue 4 (RB4), in aqueous solutions, respectively. The effects of the initial pH (2–10) of the dye solution, the adsorbent dosage (0.5–3.5 g/L), and contact time (0–540 min) were investigated in a batch system. The dynamic adsorption behavior of CV and RB4 can be represented well by the pseudo-second-order model and pseudo-first-order model, respectively. In addition, the adsorption isotherm data can be explained by the Langmuir isotherm model. Both hydrogel beads have acceptable adsorption selectivity and reusability for the study of selective adsorption and regeneration. Based on the effectiveness, selectivity, and reusability of these hydrogel beads, they can be treated as potential adsorbents for the removal of dyes in aqueous solutions.


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.


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.


2011 ◽  
Vol 704-705 ◽  
pp. 486-491
Author(s):  
Yi Nan Hao ◽  
Xi Ming Wang ◽  
Li Jun Ding ◽  
Da Yan Ma

Xanthoceras Sorbifolia Bunge hull activated carbon (XSBHAC) developed by phosphoric acid activation for removing basic fuchsin (BF) has been investigated. Experiments were carried out as function of contact time, pH (4-10) and temperature (303,313 and 323K). Adsorption isotherms were modeled with the Langmuir and Freundlich isotherms. The data fitted well with the Langmuir isotherm. The Langmuir monolayer saturation capacities of BF adsorbed onto activated carbon were 351.35, 354.96 and 355.94 mg/g at 303,313, and 323 K, respectively.The kinetic models were also studied .The rates of adsorption were found to conform to the pseudo-second-order kinetics with good correlation.Using the equilibrium concentration contents obtained at different temperatures, various thermodynamic parameters,such as △G,△H and △S, have been calculated. The thermodynamics parameters of system indicated spontaneous and endothermic process. Key words: Xanthoceras sorbifolia bunge hull;biosorption; basic fuchsin


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