scholarly journals Experimental Measurement and Modeling of Hg(II) Removal from Aqueous Solutions Using Eucalyptus globulus Bark: Effect of pH, Salinity and Biosorbent Dosage

2019 ◽  
Vol 20 (23) ◽  
pp. 5973 ◽  
Author(s):  
Elaine Fabre ◽  
Carlos Vale ◽  
Eduarda Pereira ◽  
Carlos M. Silva
Keyword(s):  
Eucalyptus Globulus ◽  
Natural Waters ◽  
Metal Removal ◽  
Ph Value ◽  
Operating Conditions ◽  
Experimental Conditions ◽  
Treatment Processes ◽  
Pseudo Second Order ◽  
Optimum Response ◽  
Available Information

Different experimental conditions were tested in order to optimize the Hg(II) removal by Eucalyptus globulus bark. Response surface methodology was applied to extract information about the significance of the factors and to obtain a model describing the sorption. The results were generated through the design of experiments by applying the methodology of a three-factor and three-level Box–Behnken design. The factors tested were pH (4.0, 6.5, and 9.0), salinity (0, 15, and 30), and biosorbent dosage (0.2, 0.5, and 0.8 g dm−3) to evaluate the Hg(II) removal using realistic conditions, such as contaminated natural waters with an initial Hg(II) concentration of 50 µg dm−3. The optimum response provided by the model was 81% of the metal removal under the optimal operating conditions: a pH value of 6.0, no salinity, and a biosorbent dosage of 0.55 g dm−3. Concerning the kinetic, the pseudo-second-order equation fitted better to the experimental results with R 2 between 0.973 and 0.996. This work highlights the promising valorization of this biomass, which is an industrial byproduct and makes available information about the influence of the variables for Hg(II) removal in water treatment processes.

scholarly journals Zeolite NaP1 Functionalization for the Sorption of Metal Complexes with Biodegradable N-(1,2-dicarboxyethyl)-D,L-aspartic Acid

Materials ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2518
Author(s):  
Dorota Kołodyńska ◽  
Yongming Ju ◽  
Małgorzata Franus ◽  
Wojciech Franus
Keyword(s):  
Experimental Data ◽  
Aspartic Acid ◽  
Ph Value ◽  
Complexing Agents ◽  
X Ray Diffraction ◽  
Experimental Conditions ◽  
Modified Zeolite ◽  
X Ray ◽  
Slow Release Fertilizers ◽  
Pseudo Second Order

The possibility of application of chitosan-modified zeolite as sorbent for Cu(II), Zn(II), Mn(II), and Fe(III) ions and their mixtures in the presence of N-(1,2-dicarboxyethyl)-D,L-aspartic acid, IDHA) under different experimental conditions were investigated. Chitosan-modified zeolite belongs to the group of biodegradable complexing agents used in fertilizer production. NaP1CS as a carrier forms a barrier to the spontaneous release of the fertilizer into soil. The obtained materials were characterized by Fourier transform infrared spectroscopy (FTIR); surface area determination (ASAP); scanning electron microscopy (SEM-EDS); X-ray fluorescence (XRF); X-ray diffraction (XRD); and carbon, hydrogen, and nitrogen (CHN), as well as thermogravimetric (TGA) methods. The concentrations of Cu(II), Zn(II), Mn(II), and Fe(III) complexes with IDHA varied from 5–20 mg/dm3 for Cu(II), 10–40 mg/dm3 for Fe(III), 20–80 mg/dm3 for Mn(II), and 10–40 mg/dm3 for Zn(II), respectively; pH value (3–6), time (1–120 min), and temperature (293–333 K) on the sorption efficiency were tested. The Langmuir, Freundlich, Dubinin–Radushkevich, and Temkin adsorption models were applied to describe experimental data. The pH 5 proved to be appropriate for adsorption. The pseudo-second order and Langmuir models were consistent with the experimental data. The thermodynamic parameters indicate that adsorption is spontaneous and endothermic. The highest desorption percentage was achieved using the HCl solution, therefore, proving that method can be used to design slow-release fertilizers.

Effect of the operating parameters on the separation of metal chelates using low pressure reverse osmosis membrane (LPROM)

2000 ◽  
Vol 41 (10-11) ◽  
pp. 135-142 ◽  
Author(s):  
Z. Ujang ◽  
G.K. Anderson
Keyword(s):  
Factorial Design ◽  
Metal Removal ◽  
Feed Solution ◽  
Metal Chelates ◽  
Operating Conditions ◽  
Operating Parameters ◽  
Operating Pressure ◽  
Permeate Flux ◽  
Experimental Conditions ◽  
Central Composite

This paper describes an investigation on the effect of operating parameters on the separation of metal chelates using LPROM. The objective of this study was to optimise the process of metal chelates removal by a LPROM using statistical factorial design. Factorial experiment by statistical design was applied, in which a central composite factorial design (half replicate) was used, then followed up by a star design to give a central composite factorial design. A bench-scale spiral wound configuration of sulphonated polysulphone LPROM was used at various operating conditions, i.e. operating conditions, solute concentrations, EDTA, pH and temperature. It has been shown experimentally that the effect of pressure is non-linear with respect to percentage of metal removal at different concentrations of metal ions in the feed solution. Observation of the response surface implies that the operating pressure was not the significant parameter in determining the percentage of zinc removal in the LPROM. The operating pressure, temperature and concentration of EDTA in the feed solution were the most significant parameters for permeate flux variation. It can also be concluded that for a given set of feed and experimental conditions, permeate flux increased linearly with operating pressure and temperature. The other parameters, i.e. the concentration of zinc in the feed solution and pH, were not statistically significant.

scholarly journals Bioadsorption characteristics of Pseudomonas aeruginosa PAOI

2014 ◽  
Vol 79 (4) ◽  
pp. 495-508 ◽  
Author(s):  
Anikó Kőnig-Péter ◽  
Béla Kocsis ◽  
Ferenc Kilár ◽  
Tímea Pernyeszi
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Ph Value ◽  
Nonlinear Least Squares ◽  
Equilibration Time ◽  
Order Kinetic ◽  
Experimental Conditions ◽  
Order Kinetic Model ◽  
Pseudo Second Order ◽  
Nonlinear Least Squares Estimation ◽  
Increasing Temperature

Biosorption of Cd(II) and Pb(II) ions from aqueous solution using lyophilized Pseudomonas aeruginosa (PAOI) cells were observed under various experimental conditions. The effect of pH, initial metal concentration, equilibration time and temperature on bioadsorption was investigated. The optimum pH value for Pb(II) adsorption was found to be 5.0, and for Cd(II) 5.0 ? 6.0. The Pb(II) and Cd(II) bioadsorption equilibrium were analyzed by using Freundlich and Langmuir model using nonlinear least-squares estimation. The experimental maximum uptake capacity of Pb(II) and Cd(II) was estimated to be 164 mg g-1 and 113 mg g-1, respectively. For biosorption kinetic study the pseudo second-order kinetic model was applied at various temperatures. The temperature had no significant effect on Pb(II) bioadsorption. In case of Cd(II) bioadsorption the adsorbed amount decreased with increasing temperature.

scholarly journals Equilibrium and Kinetics Study of Adsorption of Crystal Violet onto the Peel ofCucumis sativaFruit from Aqueous Solution

2012 ◽  
Vol 9 (3) ◽  
pp. 1091-1101 ◽  
Author(s):  
T. Smitha ◽  
S. Thirumalisamy ◽  
S. Manonmani
Keyword(s):  
Crystal Violet ◽  
Dye Removal ◽  
High Efficiency ◽  
Ph Value ◽  
Dye Adsorption ◽  
Second Order ◽  
Maximum Adsorption Capacity ◽  
Experimental Conditions ◽  
Pseudo Second Order ◽  
Cucumis Sativa

The use of low-cost, locally available, high efficiency and eco-friendly adsorbents has been investigated as an ideal alternative to the current expensive methods of removing dyes from wastewater. This study investigates the potential use of the peel ofCucumis sativafruit for the removal of crystal violet (CV) dye from simulated wastewater. The effects of different system variables, adsorbent dosage, initial dye concentration, pH and contact time were investigated and optimal experimental conditions were ascertained. The results showed that as the amount of the adsorbent increased, the percentage of dye removal increased accordingly. Optimum pH value for dye adsorption was determined as 7.0. The adsorption of crystal violet followed pseudo-second order rate equation and fit well Langmuir and Freundlich equations. The maximum removal of CV was obtained at pH 7 as 92.15% for adsorbent dose of 0.2 g/50 mL and 25 mg L-1initial dye concentration at room temperature. The maximum adsorption capacity obtained from Langmuir equation was 34.24 mg g-1. Furthermore, adsorption kinetics of (CV) was studied and the rate of adsorption was found to conform to pseudo-second order kinetics with a good correlation (R2> 0.9739). The peel ofCucumis sativafruit can be attractive options for dye removal from diluted industrial effluents since test reaction made on simulated dyeing wastewater show better removal percentage of (CV).

scholarly journals Bagasse Cellulose Grafted with an Amino-Terminated Hyperbranched Polymer for the Removal of Cr(VI) from Aqueous Solution

Polymers ◽  
2018 ◽  
Vol 10 (8) ◽  
pp. 931 ◽  
Author(s):  
Lu Xia ◽  
Zhonghang Huang ◽  
Lei Zhong ◽  
Fengwei Xie ◽  
Chak Tang ◽  
...  
Keyword(s):  
Adsorption Capacity ◽  
Hyperbranched Polymer ◽  
Metal Removal ◽  
Ph Value ◽  
Removal Rate ◽  
Heavy Metal Removal ◽  
Grafting Reaction ◽  
Pseudo Second Order ◽  
Ft Ir ◽  
Ft Ir Spectroscopy

A novel bio-adsorbent was fabricated via grafting an amino-terminated hyperbranched polymer (HBP-NH2) onto bagasse cellulose. The morphology and microstructure of the HBP-NH2-grafted bagasse cellulose (HBP-g-BC) were characterized and its adsorption capacity for Cr(VI) ions in aqueous solutions was investigated. The rough surface structure of HBP-g-BC that is beneficial for improving the adsorption capacity was observed by scanning electron microscopy (SEM). The grafting reaction was confirmed by Fourier-transform infrared (FT-IR) spectroscopy. The adsorbent performance was shown to be better with a lower pH value, a higher adsorbent dosage, or a higher initial Cr(VI) concentration. Moreover, the kinetics study revealed that the adsorption behavior followed a pseudo-second-order model. The isotherm results showed that the adsorption data could be well-fitted by the Langmuir, Freundlich, or Temkin models. Moreover, HBP-g-BC could maintain 74.4% of the initial removal rate even after five cycles of regeneration. Thus, the high potential of HBP-g-BC as a bio-adsorbent for heavy metal removal has been demonstrated.

scholarly journals Removal of Cr(VI) and Cu(II) Ions from Aqueous Solution by Carbon Prepared from Henna Leaves

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
T. Shanthi ◽  
V. M. Selvarajan
Keyword(s):  
Contact Time ◽  
Metal Ion ◽  
Metal Removal ◽  
Ph Value ◽  
Freundlich Isotherm ◽  
Isotherm Models ◽  
Lawsonia Inermis ◽  
Experimental Conditions ◽  
Initial Concentration ◽  
Adsorbent Dosage

Carbon prepared from leaves of henna (Lawsonia inermis) was used to study the adsorption of Cr(VI) and Cu(II) ions from their aqueous solutions. The experimental conditions which include pH, contact time, initial concentration, and adsorbent dosage on the metal removal were investigated. The capacity of adsorption depends on pH value; it increases with an increase in pH value from 1 to 7 and then decreases. The highest percentage of metal removal was achieved in the adsorbent dosage of 0.7 g and at an initial concentration of 100 ppm metal ion. The adsorption isotherm studies revealed that data was confirmed with both the Langmuir and Freundlich isotherm models. The removal percentage was found to be higher for Cu(II) when compared with Cr(VI). The potential of carbon prepared from henna leaves for the removal of these two solutions containing heavy metals was substantiated.

Adsorption Kinetics and Isotherms Study of Cadmium Ions from Aqueous Solution on Tailings of Steel Slag

2012 ◽  
Vol 599 ◽  
pp. 602-607 ◽  
Author(s):  
Yong Wei Hui ◽  
Li Chao An
Keyword(s):  
Adsorption Kinetics ◽  
Ph Value ◽  
Removal Rate ◽  
Steel Slag ◽  
Langmuir Model ◽  
Operating Conditions ◽  
Kinetics Equation ◽  
Cadmium Ions ◽  
Pseudo Second Order ◽  
Kinetics And Isotherms

This article explores the operating conditions of the removal of cadmium ions from wastewater by tailings of steel slag and investigates the effect of stirring rate, initial concentration of cadmium, particle size of tailings and pH value of aqueous on removal efficiency. The results show that: under proper conditions, the removal rate of cadmium ions from water on tailings of steel slag can be up to above 99.9%. The adsorption kinetics follows the pseudo-second-order kinetics equation and the adsorption isotherm conforms to the Langmuir model.

scholarly journals Enhanced removal of cationic dye by eco-friendly activated biochar derived from rice straw

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
A. I. Abd-Elhamid ◽  
Mohamed Emran ◽  
M. H. El-Sadek ◽  
Ahmed A. El-Shanshory ◽  
Hesham M. A. Soliman ◽  
...  
Keyword(s):  
Rice Straw ◽  
Contact Time ◽  
Ph Value ◽  
Active Material ◽  
Maximum Adsorption Capacity ◽  
Time Data ◽  
Experimental Conditions ◽  
Activated Biochar ◽  
Highly Active ◽  
Pseudo Second Order

AbstractThis report deals with converting the agriculture waste (rice straw) to environmental cleaner materials (biochar) using airless pyrolysis followed by eco-friendly activation. The biochar (p-Biochar) obtained after pyrolysis step (poorly active material) was activated using wet attrition method to give m-Biochar (highly active materials). The both p-Biochar and m-Biochar were characterized in detail and utilized for MB and CV dye removal from aqueous solution. Various parameters affecting the adsorption process such as dye concentration, adsorbent dose, contact time, temperature, NaCl dose and pH were investigated. The adsorption isotherm was well fitted using Langmuir isotherm, and the maximum adsorption capacity is 90.91 and 44.64 mg/g, for MB and CV dyes, respectively. The contact time data obtained showed that the two dyes were poorly adsorbed over p-Biochar. The equilibrium was reached quickly in 15 min for MB dye and 20 min for CV dye using the m-Biochar, and removal percent was 94.45 and 92.70% for MB and CV dyes, respectively. Moreover, the kinetic isotherm presented very well fitted by pseudo-second-order model. In addition, the adsorption percent increases with further increasing the pH value. Finally, we observed that m-Biochar highly adsorbs the MB dye compared with the CV dye over all experimental conditions.

scholarly journals Adsorptive Removal of Manganese from Water Intended for Consumption by Use of Cost-effective Gisenyi Volcanic Rocks

2021 ◽  
Author(s):  
Constantin Muhire ◽  
Jay Rwaka Itete
Keyword(s):  
Physical Process ◽  
Metal Removal ◽  
Influencing Factor ◽  
Volcanic Rocks ◽  
Cost Effective ◽  
Manganese Concentration ◽  
Order Kinetic ◽  
Experimental Conditions ◽  
Manganese Removal ◽  
Pseudo Second Order

Abstract This study determined the capacity of Gisenyi volcanic rocks (GVR) located in Rwanda (Nothern Province) to remove manganese from groundwater. Various experimental conditions such as adsorbent dosage and contact time were investigated. The dosage of GVR has shown to be a highly influencing factor in manganese removal from groundwater. The adsorption proceeded via a fast initial metal removal followed by a slow uptake during the first 6 h and equilibrium after 24 h. For the initial manganese concentration of 1.5 mg/L, the removal efficiency varied from 42.5–72.9% for 4g/l and 20g/l of VGR dosage respectively. The Freundlich and Languimur isotherm constants indicated that the adsorption of Mn2+ on GVR is a physical process and favorable. The pseudo-first-order and pseudo-second-order kinetic models also show that the adsorption of Mn2+ onto GVR is a physical process.

Изучение отклика дегидрогеназной активности ила на изменение технологических параметров работы аэротенка

2020 ◽  
Author(s):  
N. Zaletova ◽  
S. Zaletov
Keyword(s):  
Wastewater Treatment ◽  
Dehydrogenase Activity ◽  
Biological Treatment ◽  
Biological Process ◽  
Organic Load ◽  
Treatment Processes ◽  
Mode Of Operation ◽  
Concentrated Solution ◽  
Available Information ◽  
Complicated Mechanism

Биологический метод очистки сточных вод представляет собой сложный многокомпонентный процесс, ключевой составляющей которого является работа ферментной системы. Известно, что одним из важнейших ферментов, обеспечивающих биологический процесс, являются дегидрогеназы. Полностью сложнейший механизм действия ферментов до конца пока не раскрыт, однако в практике контроля процессов биологической очистки используется показатель дегидрогеназной активности ила. Результаты исследований позволили дополнить имеющуюся информацию фактическими данными о взаимообусловленности уровня дегидрогеназной активности ила и показателей отдельных технологических параметров биологической очистки. Показано, что режим работы аэротенков (нагрузка на ил, доза активного ила и др.) и величина показателей исходной дегидрогеназной активности и дегидрогеназной активности этого же образца ила со слабо концентрированным раствором (ДАИН2О) связаны между собой и зависят от нагрузки на ил по органическим веществам. Полученные результаты исследования могут быть использованы для контроля биологического процесса очистки сточных вод.The biological method of wastewater treatment is a comprehensive multicomponent process the activities of the enzyme system being the key component of it. It is known that dehydrogenases have been one of the most important enzymes the ensure the biological process. The complicated mechanism of the action of enzymes has not been fully described so far however, in the practice of monitoring biological treatment processes, an indicator of the dehydrogenase activity of sludge is used. The research results provided for supplementing the available information with actual data on the interdependence of the level of dehydrogenase activity of sludge and indicators of individual process parameters of biological treatment. It was shown that the mode of operation of aeration tanks (organic matter load on sludge, dose of activated sludge, etc.) and the values of the initial dehydrogenase activity and dehydrogenase activity of the same sludge sample with weakly concentrated solution (DASН2О) are interconnected and depend on the organic load on sludge. The results of the study can be used to control the biological process of wastewater treatment.The biological method of wastewater treatment is a comprehensive multicomponent process the activities of the enzyme system being the key component of it. It is known that dehydrogenases have been one of the most important enzymes the ensure the biological process. The complicated mechanism of the action of enzymes has not been fully described so far however, in the practice of monitoring biological treatment processes, an indicator of the dehydrogenase activity of sludge is used. The research results provided for supplementing the available information with actual data on the interdependence of the level of dehydrogenase activity of sludge and indicators of individual process parameters of biological treatment. It was shown that the mode of operation of aeration tanks (organic matter load on sludge, dose of activated sludge, etc.) and the values of the initial dehydrogenase activity and dehydrogenase activity of the same sludge sample with weakly concentrated solution (DASН2О) are interconnected and depend on the organic load on sludge. The results of the study can be used to control the biological process of wastewater treatment.

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