Investigation of Toxic Heavy Metal Removal Activity of Activated Coconut Husk as Solid Support Medium for Isolated Bacterial Strains

This study is focused on isolation of Ni(II), Cu(II) and Cr(VI) resistant bacteria to assess their exopolysaccharide (EPS) production and related bioremoval capacities. Mixed cultures had higher heavy metal removal capacity in media with molasses (MAS) than the control cultures lacking this carbon (AS) containing 50 mg/l of heavy metal. The yields were 32%, 75.7%, and 51.1% in MAS, while the corresponding values were 29%, 55.1%, and 34.5% in AS, respectively. Purification of the strains 1, 5 and 6 present in the mixed cultures decreased the bioremoval capacities of the mixed culture samples, although these strains produced higher EPS amounts in MAS agar. Strain 5 had the highest Cu(II) (69.1%) and Cr(VI) (43.1%) removal rates at 25 mg/l initial concentration of each pollutant with EPS amounts of 0.74 g/l and 1.05 g/l, respectively. This strain was identified as Stenotrophomonas maltophilia. The presented data show that especially mixed and also pure cultures of bacterial strains isolated from Ankara Stream could be assessed as potential bioremoval agents in the treatment of Cu(II) or Cr(VI) containing wastewaters.

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STUDY ON SYNTHESIS OF MnFe2O4/GNPs COMPOSITE AND APPLICATION ON HEAVY METAL REMOVAL

Vietnam Journal of Science and Technology ◽

10.15625/2525-2518/56/1a/12524 ◽

2018 ◽

Vol 56 (1A) ◽

pp. 204

Author(s):

Nguyen Duy Anh

Keyword(s):

Heavy Metal ◽

Metal Oxide ◽

Metal Removal ◽

Metal Oxide Nanoparticles ◽

Heavy Metal Removal ◽

Absorption Capacity ◽

Mixed Metal Oxide ◽

Oxide Nanoparticles ◽

Toxic Heavy Metal ◽

Mixed Metal

Nowadays, composite materials between mixed-metal oxides and graphene are widely studied due to their multiple applications on different fields. MnFe2O4 is a magnetic material which has the ability to absorb toxic heavy metal in water. Graphene nanoplatelets (GNPs) with about 10 layers, is one of type of graphene. GNPs was used as matrix for the fine distribution of metal oxide nanoparticles. Surface area for the absorption process can be increased. Composite was synthesized using solvothermal method, in which mixed-metal oxide nanoparticles were directly formed in-situ from precursor salts onto GNPs surface. Synthesized material was analyzed using XRD, SEM and EDX methods to determine its properties. Heavy metal absorption capacity was also studied and showed good results.

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Graphene-Based Microbots for Toxic Heavy Metal Removal and Recovery from Water

Nano Letters ◽

10.1021/acs.nanolett.6b00768 ◽

2016 ◽

Vol 16 (4) ◽

pp. 2860-2866 ◽

Cited By ~ 297

Author(s):

Diana Vilela ◽

Jemish Parmar ◽

Yongfei Zeng ◽

Yanli Zhao ◽

Samuel Sánchez

Keyword(s):

Heavy Metal ◽

Metal Removal ◽

Heavy Metal Removal ◽

Toxic Heavy Metal ◽

Removal And Recovery

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Removal of cadmium(II) ions from aqueous solution using Ni (15 wt.%)-doped α-Fe2O3 nanocrystals: equilibrium, thermodynamic, and kinetic studies

Water Science & Technology ◽

10.2166/wst.2015.245 ◽

2015 ◽

Vol 72 (4) ◽

pp. 608-615 ◽

Cited By ~ 4

Author(s):

Mohamed OuldM'hamed ◽

L. Khezami ◽

Abdulrahman G. Alshammari ◽

S. M. Ould-Mame ◽

I. Ghiloufi ◽

...

Keyword(s):

Heavy Metal ◽

Free Energy ◽

Thermodynamic Parameters ◽

Adsorption Process ◽

Metal Removal ◽

Heavy Metal Removal ◽

Kinetic Studies ◽

Entropy Change ◽

Batch Mode ◽

Toxic Heavy Metal

The present publication investigates the performance of nanocrystalline Ni (15 wt.%)-doped α-Fe2O3 as an effective nanomaterial for the removal of Cd(II) ions from aqueous solutions. The nanocrystalline Ni-doped α-Fe2O3 powders were prepared by mechanical alloying, and characterized by X-ray diffraction and a vibrating sample magnetometer. Batch-mode experiments were realized to determine the adsorption equilibrium, kinetics, and thermodynamic parameters of toxic heavy metal ions by Ni (15 wt.%)-doped α-Fe2O3. The adsorption isotherms data were found to be in good agreement with the Langmuir model. The adsorption capacity of Cd(II) ion reached a maximum value of about 90.91 mg g−1 at 328 K and pH 7. The adsorption process kinetics was found to comply with pseudo-second-order rate law. Thermodynamic parameters related to the adsorption reaction, free energy change, enthalpy change and entropy change, were evaluated. The found values of free energy and enthalpy revealed a spontaneous endothermic adsorption-process. Moreover, the positive entropy suggests an increase of randomness during the process of heavy metal removal at the adsorbent–solution interface.

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COCONUT HUSK CHAR BIOSORPTIVITY IN HEAVY METAL DIMINUTION FROM CONTAMINATED SURFACE WATER

Journal of Engineering Studies and Research ◽

10.29081/jesr.v21i4.1 ◽

2016 ◽

Vol 21 (4) ◽

Author(s):

ADEMOLA AJAYI-BANJI AJAYI-BANJI

Keyword(s):

Heavy Metal ◽

Surface Water ◽

Contact Time ◽

Metal Removal ◽

Heavy Metal Removal ◽

Column Experiment ◽

Freundlich Isotherm ◽

Coconut Husk ◽

Biosorption Mechanism ◽

Isotherm And Kinetic Models

<span>Applicability of coconut husk char in heavy metal removal was examined in the study. The surface morphology and elemental compositions of the char was investigated with SEM-EDX machine. Heavy metals sorption on 100 g of the char dosage was studied under five different contact times in the column experiment. Isotherm and kinetic models were the probing tools for biosorption mechanism prediction. Results indicated removal efficiency for chromium, cobalt, cadmium, aluminum and arsenic at 60 mins contact time were 72, 80, 86, 89 and 100 % respectively. Contaminate removal depends on metal involved and sorption contact time. Adsorption data are fitted well into Freundlich isotherm model (R2 > 0.92). Pseudo kinetic second order well described the adsorption process, with most R2 values ≥ 0.94. Coconut husk char is an effective biosorbent in sequestration of arsenic, cadmium, aluminum and cobalt in contaminated surface water.</span>

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Cooperation between two Thiobacillus strains for heavy-metal removal from municipal sludge

Canadian Journal of Microbiology ◽

10.1139/m92-031 ◽

1992 ◽

Vol 38 (3) ◽

pp. 181-187 ◽

Cited By ~ 60

Author(s):

J.-F. Blais ◽

J. C. Auclair ◽

R. D. Tyagi

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Sewage Sludge ◽

Mixed Culture ◽

Metal Removal ◽

Heavy Metal Removal ◽

Municipal Sewage ◽

Municipal Sewage Sludge ◽

Municipal Sludge ◽

Bacterial Strains

A mixed culture of two fast-growing bacterial strains for heavy-metal solubilization of municipal sewage sludge has been developed. Strain VA-7 decreases the initial sludge pH (7–8.5) to a value between 4.0 and 4.5. Then, strain VA-4 begins growing and further reduces the pH to values below 2.0. The rapid decrease of sludge pH by a mixed culture through sulfur oxidation into sulfuric acid solubilizes the toxic metals (Cd 83–96%, Cr 16–54%, Cu 85–87%, Mn 91–94%, Ni 78–79%, Pb 28–46%, Zn 82–96%) to levels recommended for intensive use of residual sludge in agriculture. A study of the physiological and metabolic characteristics of these strains revealed that isolate VA-7 is a strain of Thiobacillus thioparus (ATCC 55127), while isolate VA-4 corresponds to a Thiobacillus thiooxidans (ATCC 55128). These bacterial strains possess distinctive physiological characteristics that allow them to easily grow and solubilize heavy metals in municipal sludge. Key words: heavy metals, sewage sludge, thiobacilli, bioleaching, elemental sulfur.

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COCONUT HUSK CHAR BIOSORPTIVITY IN HEAVY METAL DIMINUTION FROM CONTAMINATED SURFACE WATER

Journal of Engineering Studies and Research ◽

10.29081/jesr.v21i4.127 ◽

2015 ◽

Vol 21 (4) ◽

pp. 7-13

Author(s):

AJAYI-BANJI ADEMOLA ◽

SANGODOYIN ABIMBOLA ◽

IJAOLA OPOLOLA

Keyword(s):

Heavy Metal ◽

Surface Water ◽

Contact Time ◽

Metal Removal ◽

Heavy Metal Removal ◽

Column Experiment ◽

Freundlich Isotherm ◽

Coconut Husk ◽

Biosorption Mechanism ◽

Isotherm And Kinetic Models

Applicability of coconut husk char in heavy metal removal was examined in the study. The surface morphology and elemental compositions of the char was investigated with SEM-EDX machine. Heavy metals sorption on 100 g of the char dosage was studied under five different contact times in the column experiment. Isotherm and kinetic models were the probing tools for biosorption mechanism prediction. Results indicated removal efficiency for chromium, cobalt, cadmium, aluminum and arsenic at 60 mins contact time were 72, 80, 86, 89 and 100 % respectively. Contaminate removal depends on metal involved and sorption contact time. Adsorption data are fitted well into Freundlich isotherm model (R2 > 0.92). Pseudo kinetic second order well described the adsorption process, with most R2 values ≥ 0.94. Coconut husk char is an effective biosorbent in sequestration of arsenic, cadmium, aluminum and cobalt in contaminated surface water.

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