scholarly journals Removal of hexavalent chromium by chemical modification of 4,4′-((1Z,11Z)-2,5,8,11-tetraazadodeca-1,8-diene-1,11-diyl)diphenol: kinetic and equilibrium modeling

2015 ◽  
Vol 5 (3) ◽  
pp. 312-325
Author(s):  
Aysel Çimen
Keyword(s):  
Metal Ions ◽  
Contact Time ◽  
Industrial Wastewater ◽  
Heavy Metal Ions ◽  
Atomic Absorption Spectrometer ◽  
Equilibrium Modeling ◽  
Chromium Vi ◽  
Adsorption Capacities ◽  
Isotherm Equations ◽  
Surface Modified

This study aimed to synthesize a new resin through immobilization of the 4,4′-((1Z,11Z)-2,5,8,11-tetraazadodeca-1,8-diene-1,11-diyl)diphenol (TRA) onto silica gel modified (Si-CPTS) with 3-chloropropyltrimethoxy silane (CPTS) and its application for the removal of chromium(VI) ions from aqueous solution as well as from industrial wastewater. The same applications were also made for industrial wastewater vapor. The objective purpose of this work was to investigate the influences of concentration, temperature, amount of metal ions, contact time and pH to sorption on the surface modified by TRA (Si-TRA). The newly synthesized Si-TRA is characterized with scanning electron microscope and elemental analysis and Cr(VI) heavy metal ions were used as sorbate. The sorption of Cr(VI) ion was evaluated by using batch methods. The value of adsorption of Cr(VI) ion was detected with an atomic absorption spectrometer. The maximum adsorption capacities and isotherm parameters were calculated from the Langmuir, Freundlich, and Dubinin–Radushkevich isotherm equations. Thermodynamic parameters such as free energy (ΔG°), entropy (ΔS°), and enthalpy (ΔH°) were also calculated from the sorption results. The modified structure used as adsorbent was successfully employed in the removal of Cr(VI) ions from the samples of industrial wastewater.

scholarly journals Adsorption of Chromium(VI) and Zinc(II) Ions on the Skin of Orange Peels (Citrus sinensis)

1970 ◽  
Vol 26 ◽  
pp. 31-39 ◽  
Author(s):  
O. A. Ekpete ◽  
F. Kpee ◽  
J. C. Amadi ◽  
R. B. Rotimi
Keyword(s):  
Heavy Metals ◽  
Metal Ions ◽  
Citrus Sinensis ◽  
Contact Time ◽  
Heavy Metal Ions ◽  
Orange Peel ◽  
Maximum Adsorption Capacity ◽  
Orange Peels ◽  
Chromium Vi ◽  
Aas Method

The removal of heavy metal ions Cr (VI) and Zn (II) from aqueous solution using theskin of orange peel (Citrus sinensis) as an adsorbent under different experimentalconditions was investigated in this study. The concentrations of the metal ions adsorbedwere determined by atomic absorption spectroscopic (AAS) method. The parametersinvestigated were temperature, contact time, adsorbent dosage, initial metal ionsconcentration and pH. It was observed that the white inner skin of orange removed more ofCr (VI) than Zn (II) metal ions in all the adsorption experiments. The optimum removal ofthe Cr (VI) and Zn (II) metal ions occurred at pH 3 and at temperature 30°C. Application ofthe Langmuir isotherm to the systems yielded maximum adsorption capacity of 8.068 (mg/g)and 1.078 (mg/g) for Cr (VI) and Zn (II) metal ions respectively.Keywords: Orange peel; Adsorption; Heavy metals; LangmuirDOI: 10.3126/jncs.v26i0.3628Journal of Nepal Chemical SocietyVol. 26, 2010Page:31-39

scholarly journals Biosorption of copper(II) and chromium(VI) by modified tea fungus

2012 ◽  
pp. 335-342 ◽  
Author(s):  
Marina Sciban ◽  
Jelena Prodanovic ◽  
Radojka Razmovski
Keyword(s):  
Heavy Metal ◽  
Aqueous Solutions ◽  
Metal Ions ◽  
Heavy Metal Ions ◽  
Acid Modification ◽  
Adsorption Ability ◽  
Batch Mode ◽  
Chromium Vi ◽  
Adsorption Capacities ◽  
Tea Fungus

The tea fungus was found to have good adsorption capacities for heavy metal ions. In this work it was treated with HCl or NaOH at 20?C or 100?C, with the aim to improve its adsorption ability. The sorption of Cu(II) and Cr(VI) ions from aqueous solutions by raw and treated tea fungus was investigated in the batch mode. The largest quantity of adsorbed Cu(II), of about 55 mg/g, was achieved by tea fungus modified with NaOH at 100?C. For Cr(VI), the largest quantity of adsorbed anions, of about 58 mg/g, was achieved by the adsorbent modified with NaOH at 20?C. It was shown that acid modification of tea fungus biomass was not effective.

scholarly journals Lettuce Leaves as Biosorbent Material to Remove Heavy Metal Ions from Industerial Wastewater

2014 ◽  
Vol 11 (3) ◽  
pp. 1164-1170
Author(s):  
Baghdad Science Journal
Keyword(s):  
Heavy Metal ◽  
Environmental Factors ◽  
Metal Ions ◽  
Contact Time ◽  
Industrial Wastewater ◽  
Heavy Metal Ions ◽  
Current Data ◽  
Zinc Ions ◽  
Biosorption Capacity ◽  
Copper And Zinc

The current study was designed to remove Lead, Copper and Zinc from industrial wastewater using Lettuce leaves (Lactuca sativa) within three forms (fresh, dried and powdered) under some environmental factors such as pH, temperature and contact time. Current data show that Lettuce leaves are capable of removing Lead, Copper and Zinc ions at significant capacity. Furthermore, the powder of Lettuce leaves had highest capability in removing all metal ions. The highest capacity was for Lead then Copper and finally Zinc. However, some examined factors were found to have significant impacts upon bioremoval capacity of studied ions, where best biosorption capacity was found at pH 4, at temperature 50º C and contact time of 1 hour.

scholarly journals Synthesis and Adsorption Properties of Novel Bacterial Cellulose/Graphene Oxide/Attapulgite Materials for Cu and Pb Ions in Aqueous Solutions

Materials ◽  
2020 ◽  
Vol 13 (17) ◽  
pp. 3703 ◽  
Author(s):  
Shen Song ◽  
Zhao Liu ◽  
Ji Zhang ◽  
Caizhen Jiao ◽  
Ling Ding ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Graphene Oxide ◽  
Polyvinyl Alcohol ◽  
Metal Ions ◽  
Bacterial Cellulose ◽  
Industrial Wastewater ◽  
Heavy Metal Ions ◽  
Adsorption Process ◽  
Adsorption Capacities ◽  
Dsc Analyses

Removing heavy metal ions from industrial wastewater is one of the most important and difficult areas of the water treatment industry. In this study, Bacterial Cellulose/Polyvinyl Alcohol/Graphene Oxide/Attapulgite (BC/PVA/GO/APT) composites were successfully prepared via a repeated freeze-thaw method using bacterial cellulose, polyvinyl alcohol as the skeleton, and graphene oxide, attapulgite as fillers. The capacities of adsorbing Cu2+ and Pb2+ ions in solution were investigated. FTIR, XRD, SEM, BET, and TG-DSC analyses showed that the BC/PVA/GO/APT hydrogel has a better hydrophilicity, a larger specific surface area and a better thermal stability than traditional materials. We found that the adsorption of Cu2+ and Pb2+ ions can be accurately predicted by the Freundlich kinetic model, and the optimal adsorption capacities of these ions were found to be 150.79 mg/g and 217.8 mg/g respectively. Thermodynamic results showed that the adsorption process is spontaneous and exothermic. BC/PVA/GO/APT composites are suggested to be an ideal adsorption material for removing heavy metal ions from industrial wastewater.

The adsorption of divalent heavy metal ions on (8,0) carbon nanotubes: The first-principles study

2020 ◽  
Vol 34 (32) ◽  
pp. 2050368
Author(s):  
Z. Zhu ◽  
L. An ◽  
T. Chen ◽  
X. Jia
Keyword(s):  
Carbon Nanotubes ◽  
Heavy Metal ◽  
Metal Ions ◽  
First Principles ◽  
Industrial Wastewater ◽  
Heavy Metal Ions ◽  
Density Functional ◽  
Physical Adsorption ◽  
Functional Theory ◽  
Sensing Material

In order to explore new ways to detect and remove heavy metal ions from industrial wastewater, the first-principles method based on density functional theory has been used to investigate the performance of carbon nanotubes (CNTs) in adsorbing divalent heavy metal ions which include Zn[Formula: see text], Cu[Formula: see text], Pb[Formula: see text] and Sn[Formula: see text]. Results show that the adsorption of Zn[Formula: see text] on CNTs is weak and only physical adsorption forms between them. However, for Cu[Formula: see text], Pb[Formula: see text] and Sn[Formula: see text], the final adsorption distance with CNTs is greatly decreased, and the adsorption energy and charge transfer amount with CNTs are significantly increased. In addition, the charge density of Cu[Formula: see text], Pb[Formula: see text] and Sn[Formula: see text] overlaps effectively with that of CNTs. These indicate the formation of strong chemisorption between these ions and CNTs. Therefore, CNTs could be used as a sensing material to detect and remove Cu[Formula: see text], Pb[Formula: see text] and Sn[Formula: see text] from wastewater. The research provides theoretical guidance for the application of CNTs in heavy metal ions treatment.

Adsorption of Heavy Metal Ions by Chelate-Fiber Prepared by Chemical Surface Modification

2011 ◽  
Vol 308-310 ◽  
pp. 178-181
Author(s):  
Xin Liang Liu ◽  
Li Jun Wang ◽  
Yong Li Chen ◽  
Nan Chen ◽  
Shuang Fei Wang
Keyword(s):  
Heavy Metal ◽  
Metal Ions ◽  
Heavy Metal Ions ◽  
Optimal Process ◽  
Order Model ◽  
Chemical Surface ◽  
Adsorption Capacities ◽  
Chemical Surface Modification ◽  
Pseudo Second Order ◽  
Mechanism Of Sorption

The bagasse fibers were activated by alkalize and etherified. 1,2-ethanediamine and carbon disulfide were used to modify the etherify fiber to get the chelate-fiber contained sulfur and nitrogen. The FTIR was used to characterize the xanthated aminating-fiber (XAF). The mechanism of sorption properties for heavy metal ions were studied. As the results shown, the optimal process to prepare the XAF was that the reaction time, concentration of NaOH and dosage of CS2 was 60min, 12% and 2mL, respectively. The chelate-fiber containing sulfur and nitrogen possessed high adsorption capacities for Cu(II) and the mechanism of sorption fitted the pseudo-second-order model well.

Bioremediation of heavy metal contaminated aqueous solution by using red algae Porphyra leucosticta

2015 ◽  
Vol 72 (9) ◽  
pp. 1662-1666 ◽  
Author(s):  
Jianjun Ye ◽  
Henglin Xiao ◽  
Benlin Xiao ◽  
Weisheng Xu ◽  
Linxia Gao ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Metal Ions ◽  
Red Algae ◽  
Contact Time ◽  
Heavy Metal Ions ◽  
Industrial Effluent ◽  
Optimal Conditions ◽  
Removal Capacity ◽  
Experimental Parameters ◽  
Biomass Dosage

Bioremediation is an effective process for the removal and recovery of heavy metal ions from aqueous solutions. In this study, red algae Porphyra leucosticta was examined to remove Cd(II) and Pb(II) ions from wastewater through biological enrichment and biological precipitation. The experimental parameters that affect the bioremediation process such as pH, contact time and biomass dosage were studied. The maximum bioremediation capacity of metal ions was 31.45 mg/g for Cd(II) and 36.63 mg/g for Pb(II) at biomass dosage 15 g/L, pH 8.0 and contact time 120 minutes containing initial 10.0 mg/L of Cd(II) and 10.0 mg/L of Pb(II) solution. Red algae Porphyra leucosticta biomass was efficient at removing metal ions of 10.0 mg/L of Cd(II) and 10.0 mg/L of Pb(II) solution with bioremediation efficiency of 70% for Cd(II) and 90% for Pb(II) in optimal conditions. At the same time, the removal capacity for real industrial effluent was gained at 75% for 7.6 mg/L Cd(II) and 95% for 8.9 mg/L Pb(II). In conclusion, it is demonstrated that red algae Porphyra leucosticta is a promising, efficient, cheap and biodegradable sorbent biomaterial for reducing heavy metal pollution in the environment and wastewater.

scholarly journals Polyaniline Modified with Cobalt-Hexacyanoferrate (PmCH) as an Adsorbent for Removal of Heavy Metals from Aqueous Solutions

2018 ◽  
Vol 51 ◽  
pp. 03004
Author(s):  
Nima Moazezi ◽  
Mohammad Ali Moosavian
Keyword(s):  
Heavy Metals ◽  
Ionic Strength ◽  
Aqueous Solutions ◽  
Metal Ions ◽  
Contact Time ◽  
Ion Concentration ◽  
Adsorption Capacities ◽  
Cobalt Hexacyanoferrate ◽  
Optimum Ph ◽  
Removal Of Heavy Metals

In this study, polyaniline modified with cobalt-hexacyanoferrate (PmCH) composite was synthesized and characterized for removal of Rb+, Cd2+, Zn2+, Pb2+, and Ni2+ by FTIR and XRD. The effect of pH, adsorbent dosage, ionic strength, contact time, initial ion concentration, and temperature were studied. The competition adsorption experiments between metal ions were investigated. Batch desorption was also conducted to evaluate the reusability of PmCH. The maximum adsorption capacities were 96.15, 27.17, 17.85, 19.15, and 4.76 mg g-1 of Rb+, Cd2+, Zn2+, Pb2+, and Ni2+, respectively. The optimum pH was determined at natural pH of each solution.

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