scholarly journals Adsorption capability of brewed tea waste in waters containing toxic lead(II), cadmium (II), nickel (II), and zinc(II) heavy metal ions

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Hakan Çelebi ◽  
Gülden Gök ◽  
Oğuzhan Gök

Abstract Recently, the search for low-cost eco-friendly adsorbents has become one of the main objectives of researchers. The aim of this study was to test the removal of four heavy metals, namely lead (Pb), zinc (Zn), nickel (Ni) and cadmium (Cd), from a simulated watery solution using brewed tea waste as a potentially suitable adsorbent. The effects of pH levels (2.0–6.0), adsorbent amount (0.1–5.0 g), contact times (1–150 min.) were examined throughout the adsorption process. The results of the experiments showed that the heavy metals elimination yields had an inverse relationship with pH and a linear relationship between the other parameters. The optimum pH for the removal of the heavy metals was between 4.0 and 5.0 in the case of the brewed tea waste. Equilibrium times of 2, 10, 30 and 5 min were required for the adsorption of Pb, Zn, Ni, Cd onto Camellia sinensis, respectively. Based on the results of this study it can be said that brewed tea waste has a high potential to remove heavy metals from aqueous solutions. The maximum adsorption capacities were calculated as 1.197, 1.457, 1.163 and 2.468 mg/g, for Pb, Zn, Ni and Cd, respectively, by fitting the equilibrium data to the Langmuir isotherm model.

2011 ◽  
Vol 393-395 ◽  
pp. 1098-1101 ◽  
Author(s):  
Yan Yu ◽  
Feng Yuan Huang

In the present paper, the ability of carboxymethylcellulose sulfate (CMC-S) for Cu(II) removal was studied. The influence of factors, such as the pH value, the initial copper concentrations, and the contact time, were investigated in detail. Atomic absorption spectrophotometer was applied to determined the concentration of Cu(II). The results showed that the adsorption process was strongly dependent on the pH value and the initial copper concentration. The optimum pH value was in the range of 6-7. The theoretical adsorption capacities for Cu(II) was 127.7 mg/g. The equilibrium data was well fitted to the Langmuir isotherm model at 25°C, which can be explained as a monolayer adsorption.


2012 ◽  
Vol 27 ◽  
pp. 107-114
Author(s):  
Jagjit Kour ◽  
P. L. Homagai ◽  
M. R. Pokherel ◽  
K. N. Ghimire

The industrial discharge of heavy metals into waters' course is one of the major pollution problems affecting water quality. Therefore, they must be removed prior to their discharge into waste streams. An efficient and low-cost bioadsorbent has been investigated from Desmostachya bipinnata (Kush) by charring with concentrated sulphuric acid and functionalized with dimethylamine.It was characterised by SEM, FTIR and elemental analysis. The effect of pH, initial concentration and contact time of the metal solution was monitered by batch method. The maximum adsorption capacities were determined for Cd and Zn at their optimum pH 6. The equilibrium data were analysed using Langmuir and Freundlich isotherm models. Langmuir isotherm model fitted well and the rate of adsorption followed the pseudo second order kinetic equation.DOI: http://dx.doi.org/10.3126/jncs.v27i1.6669 J. Nepal Chem. Soc., Vol. 27, 2011 107-114  


2021 ◽  
Author(s):  
Zhiyu Huang ◽  
Peng Wu ◽  
Yankun Yin ◽  
Xiang Zhou ◽  
Lu Fu ◽  
...  

Abstract In order to prepare low-cost and environmentally friendly adsorbent materials for adsorption of heavy metal ion, two kinds of novel modified cottons (C-4-APD and C-2-APZ) were obtained by introducing 4-aminopyridin and 2-aminopyrazine into the surface of degreasing cotton, respectively, and used for the removal of Cr(VI) ions from aqueous solution. The two modified cottons were characterized by Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS), which confirmed the amino groups, pyridine groups and pyrazine groups grafted onto the surface of modified cottons. The maximum adsorption capacities of C-4-APD and C-2-APZ were 73.78 mg/g and 61.34 mg/g, respectively, at the optimum pH of 6 and an initial concentration of 200 mg/g. Kinetic and isotherm studies were carried out to investigate the adsorption behavior of the modified cottons on Cr(VI) ions. The results showed that the adsorption of Cr(VI) ions by modified cottons followed a pseudo-second-order kinetic model, the equilibrium data were in good agreement with the Langmuir isotherm model, and electrostatic and chemisorption may be the main adsorption mechanisms. The recovery and reuse of modified cotton were achieved by washing with 2 wt% thiourea-hydrochloric acid solution (0.5 mol/L concentration of HCl), and the adsorption capacities of C-4-APD and C-2-APZ were maintained above 90% and 80%, respectively, after six cycles.


2014 ◽  
Vol 11 (3) ◽  
pp. 1373-1380
Author(s):  
Abeer Al Saharty

The Bean Plants were used in this work as low cost adsorbent material for removal of Pb(II), Cd(II) and Zn(II) ions from aqueous solutions. The samples were prepared and sorted according to the particles diameter by standard sieves 250 - 500 µm. Batch adsorption experiments were carried out to study the adsorption process pH of adsorbent, effect of contact time, effect of adsorbent amount and effect of metal concentration were Investigated in these experiments. The effect of any one of those previously mentioned parameters on the adsorption capacity were studied while the other parameters were kept constant. The maximum adsorption capacities of beans for the removal of selected heavy metals were very high. It is suggested to use it as a low coast adsorbent material to clean up the water in the environment from toxic heavy metals.


2021 ◽  
pp. 34-44
Author(s):  
Yanasinee Suma ◽  
Nittaya Pasukphun ◽  
Numfon Eaktasang

Elephant dung biochar (ED350) prepared by controlled heating at 350 ºC was used to adsorb methylene blue (MB) in an aqueous solution. The effects of adsorption time, pH, adsorbent dosage, and initial MB concentration were examined. Kinetic, isotherm, and thermo-dynamic models were then further analyzed to determine the adsorption. The results show that ED350 was found to be efficient within 180 min. The optimum pH of MB adsorption was 11. The Langmuir isotherm model was found to be the most suitable fit for the adsorption equilibrium data, with ED350 having a homogeneous surface. The calculated equilibrium parameter (RL) values were greater than zero and less than one, indicating a favorable adsorption process and that ED350 was an efficient adsorbent for MB removal. The kinetics of MB adsorption onto ED350 obeys the pseudo-second-order model. The results of thermo-dynamic data consideration reveal that the adsorption process is spontaneous and exothermic in nature. This finding suggests that ED350 may prove to be an efficient low-cost adsorbent of MB from wastewater.


2012 ◽  
Vol 9 (3) ◽  
pp. 1457-1480 ◽  
Author(s):  
R. Bhaumik ◽  
N. K. Mondal ◽  
B. Das ◽  
P. Roy ◽  
K. C. Pal ◽  
...  

A new medium, eggshell powder has been developed for fluoride removal from aqueous solution. Fluoride adsorption was studied in a batch system where adsorption was found to be pH dependent with maximum removal efficiency at 6.0. The experimental data was more satisfactorily fitted with Langmuir isotherm model. The kinetics and the factor controlling adsorption process fully accepted by pseudo-second-order model were also discussed. Eawas found to be 45.98 kJmol-1by using Arrhenius equation, indicating chemisorption nature of fluoride onto eggshell powder. Thermodynamic study showed spontaneous nature and feasibility of the adsorption process with negative enthalpy (∆H0) value also supported the exothermic nature. Batch experiments were performed to study the applicability of the adsorbent by using fluoride contaminated water collected from affected areas. These results indicate that eggshell powder can be used as an effective, low-cost adsorbent to remove fluoride from aqueous solution as well as groundwater.


2020 ◽  
Vol 81 (1) ◽  
pp. 159-169
Author(s):  
Feyza Ergüvenerler ◽  
Şerif Targan ◽  
Vedia Nüket Tirtom

Abstract Simple, fast, effective, low cost and waste biosorbents, lemon, bean and artichoke shells, were used to remove lead (II) ions from aqueous solution. The influence of pH, contact time, temperature and lead (II) concentration of the removal process was investigated. The sufficient contact time was deemed 10 minutes for bean and artichoke shells and 60 minutes for lemon shells for Pb(II) ions. The thermodynamic parameters, such as standard free energy (ΔG), standard enthalpy (ΔH), and standard entropy (ΔS) of the adsorption process were calculated as −5.6786, −5.5758, −3.1488 kJmol−1 for ΔG, −7.2791, −20.285, −9.5561 kJ mol−1 for ΔH, −0.00545, −0.05017, −0.02185 kJ mol−1 K−1 for ΔS, respectively, for lemon, artichoke and bean shells. Maximum adsorption capacities of lead (II) were observed as 61.30 mg g−1, 88.5 mg g−1 and 62.81 mg g−1, respectively, for lemon, bean and artichoke shells according to the Freundlich isotherm model at 20 °C. Scanning electron microscope (SEM) and energy-dispersive X-ray detector (EDX) were used to characterize the surface morphology of the adsorbents. Consequently, Pb(II) removal using lemon, bean and artichoke shells would be an effective method for the economic treatment of wastewater.


2016 ◽  
Vol 7 (4) ◽  
pp. 387-419 ◽  
Author(s):  
Renu ◽  
Madhu Agarwal ◽  
K. Singh

Heavy metals are discharged into water from various industries. They can be toxic or carcinogenic in nature and can cause severe problems for humans and aquatic ecosystems. Thus, the removal of heavy metals from wastewater is a serious problem. The adsorption process is widely used for the removal of heavy metals from wastewater because of its low cost, availability and eco-friendly nature. Both commercial adsorbents and bioadsorbents are used for the removal of heavy metals from wastewater, with high removal capacity. This review article aims to compile scattered information on the different adsorbents that are used for heavy metal removal and to provide information on the commercially available and natural bioadsorbents used for removal of chromium, cadmium and copper, in particular.


2013 ◽  
Vol 20 (02) ◽  
pp. 1350021
Author(s):  
SADAF BHUTTO ◽  
M. NASIRUDDIN KHAN

The low-cost modified activated carbons were prepared from Thar and Lakhra (Pakistan) coals by activation with sulfuric acid and further modified with citric, tartaric and acetic acids for the selective adsorption of Cu(II) from aqueous solution. The original carbon obtained from activated Thar and Lakhra coals at pH 3.0 displayed significant adsorption capacity for lead and insignificant capacity values (0.880 and 0.830 mg⋅g-1) for copper. However, after modification with citric, tartaric and acetic acid the copper adsorption capacities enhanced in the range of 5.56–21.85 and 6.05–44.61 times, respectively. The Langmuir, Freundlich and Temkin adsorption isotherms were used to elucidate the observed sorption phenomena. The isotherm equilibrium data was well fitted by the Langmuir and sufficiently fitted to the Freundlich models. The calculated thermodynamic parameters such as change in Gibbs free energy (ΔG°), enthalpy (ΔH°) and entropy (ΔS°) inferred that the investigated adsorption was spontaneous and endothermic in nature. Based on the results, it was concluded that the surface alteration with citric and tartaric acid, Thar and Lakhra activated carbons had significant potential for selective removal of copper(II) from industrial wastewater.


2018 ◽  
Vol 156 ◽  
pp. 03014
Author(s):  
Sudarat Sertsing ◽  
Thanaphat Chukeaw ◽  
Sitthiphong Pengpanich ◽  
Bawornpong Pornchuti

In this study, silica aerogel was synthesized by drying at atmospheric pressure and modified further with aminopropyl triethoxysilane (APTES). The amine-functionalized silica aerogel was investigated as an adsorbent for removal of nickel and chromium ions. The effect of contact time, solution pH, and initial solution concentration were studied. The equilibrium was achieved within 60 min. The optimum pH was found to be 4. Adsorption equilibrium data were agreed fairly well with Langmuir isotherm model. Adsorption capacities for nickel and chromium ions were found to be 40.32 mg/g and 46.08 mg/g, respectively.


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