Plant-Based Tacca leontopetaloides Biopolymer Flocculant (TBPF) Produced High Removal of Heavy Metal Ions at Low Dosage

High removal of heavy metals using plant-based bioflocculant under low concentration is required due to its low cost, abundant source, and nontoxicity for improved wastewater management and utilization in the water industry. This paper presents a treatment of synthetic wastewater using plant-based Tacca leontopetaloides biopolymer flocculant (TBPF) without modification on its structural polymer chains. It produced a high removal of heavy metals (Zn, Pb, Ni, and Cd) at a low concentration of TBPF dosage. In our previous report, TBPF was characterized and successfully reduced the turbidity, total suspended solids, and color for leachate treatment; however, its effectiveness for heavy metal removal has not been reported. The removal of these heavy metals was performed using a standard jar test procedure at different pH values of synthetic wastewater and TBPF dosages. The effects of hydroxide ion, pH, initial TBPF concentration, initial metal ion concentration, and TBPF dosage were examined using one factorial at the time (OFAT). The results show that the highest removal for Zn, Pb, Ni, and Cd metal ions were 98.4–98.5%, 79–80%, 97–98%, and 92–93%, respectively, using 120 mg/L dosage from the initial concentration of 10% TBPF at pH 10. The final concentrations for Zn, Pb, Ni, and Cd metal ions were 0.043–0.044, 0.41–0.43, 0.037–0.054, and 0.11–0.13 mg/L, respectively, which are below the Standard B discharge limit set by the Department of Environment (DOE), Malaysia. The results show that TBPF has a high potential for the removal of heavy metals, particularly Zn, Pb, Ni, and Cd, in real wastewater treatment.

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Adsorption of Hexavalent Chromium and Divalent Lead Ions on the Nitrogen-Enriched Chitosan-Based Activated Carbon

Nanomaterials ◽

10.3390/nano11081907 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1907

Author(s):

Fatma Hussain Emamy ◽

Ali Bumajdad ◽

Jerzy P. Lukaszewicz

Keyword(s):

Heavy Metal ◽

Activated Carbon ◽

Metal Ions ◽

Metal Removal ◽

High Surface ◽

Heavy Metal Removal ◽

High Surface Area ◽

Kinetics Of Adsorption ◽

Removal Of Heavy Metals ◽

Pseudo Second Order

Optimizing the physicochemical properties of the chitosan-based activated carbon (Ch-ACs) can greatly enhance its performance toward heavy metal removal from contaminated water. Herein, Ch was converted into a high surface area (1556 m2/g) and porous (0.69 cm3/g) ACs with large content of nitrogen (~16 wt%) using K2CO3 activator and urea as nitrogen-enrichment agents. The prepared Ch-ACs were tested for the removal of Cr(VI) and Pb(II) at different pH, initial metal ions concentration, time, activated carbon dosage, and temperature. For Cr(VI), the best removal was at pH = 2, while for Pb(II) the best pH for its removal was in the range of 4–6. At 25 °C, the Temkin model gives the best fit for the adsorption of Cr(VI), while the Langmuir model was found to be better for Pb(II) ions. The kinetics of adsorption of both heavy metal ions were found to be well-fitted by a pseudo-second-order model. The findings show that the efficiency and the green properties (availability, recyclability, and cost effectiveness) of the developed adsorbent made it a good candidate for wastewaters treatment. As preliminary work, the prepared sorbent was also tested regarding the removal of heavy metals and other contaminations from real wastewater and the obtained results were found to be promising.

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A systematic study for removal of heavy metals from aqueous media using Sorghum bicolor: an efficient biosorbent

Water Science & Technology ◽

10.2166/wst.2018.190 ◽

2018 ◽

Vol 77 (10) ◽

pp. 2355-2368 ◽

Cited By ~ 5

Author(s):

Khalida Naseem ◽

Zahoor H. Farooqi ◽

Muhammad Z. Ur Rehman ◽

Muhammad A. Ur Rehman ◽

Robina Begum ◽

...

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Metal Ions ◽

Heavy Metal Ions ◽

Aqueous Media ◽

Review Article ◽

Isotherm Models ◽

Adsorption Efficiency ◽

Adsorption Isotherm Models ◽

Removal Of Heavy Metals

Abstract This review is based on the adsorption characteristics of sorghum (Sorghum bicolor) for removal of heavy metals from aqueous media. Different parameters like pH, temperature of the medium, sorghum concentration, sorghum particle size, contact time, stirring speed and heavy metal concentration control the adsorption efficiency of sorghum biomass for heavy metal ions. Sorghum biomass showed maximum efficiency for removal of heavy metal ions in the pH range of 5 to 6. It is an agricultural waste and is regarded as the cheapest biosorbent, having high adsorption capacity for heavy metals as compared to other reported adsorbents, for the treatment of heavy metal polluted wastewater. Adsorption of heavy metal ions onto sorghum biomass follows pseudo second order kinetics. Best fitted adsorption isotherm models for removal of heavy metal ions on sorghum biomass are Langmuir and Freundlich adsorption isotherm models. Thermodynamic aspects of heavy metal ions adsorption onto sorghum biomass have also been elaborated in this review article. How adsorption efficiency of sorghum biomass can be improved by different physical and chemical treatments in future has also been elaborated. This review article will be highly useful for researchers working in the field of water treatment via biosorption processing. The quantitative demonstrated efficiency of sorghum biomass for various heavy metal ions has also been highlighted in different sections of this review article.

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Heavy metal removal from wastewater and leachate co-treatment sludge by sulfur oxidizing bacteria

Water Science & Technology ◽

10.2166/wst.2001.0579 ◽

2001 ◽

Vol 44 (10) ◽

pp. 53-58 ◽

Cited By ~ 7

Author(s):

L. C. Aralp ◽

A. Erdincler ◽

T. T. Onay

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Municipal Wastewater ◽

Metal Removal ◽

Heavy Metal Removal ◽

Heavy Metal Concentration ◽

Organic Content ◽

Removal Of Heavy Metals ◽

Sulfur Oxidizing ◽

Sulfur Oxidizing Bacteria

Heavy metal concentration in sludge is one of the major obstacles for the application of sludge on land. There are various methods for the removal of heavy metals in sludge. Using sulfur oxidizing bacteria for microbiological removal of heavy metals from sludges is an outstanding option because of high metal solubilization rates and the low cost. In this study, bioleaching by indigenous sulfur oxidizing bacteria was applied to sludges generated from the co-treatment of municipal wastewater and leachate for the removal of selected heavy metals. Sulfur oxidizing bacteria were acclimated to activated sludge. The effect of the high organic content of leachate on the bioleaching process was investigated in four sets of sludges having different concentrations of leachate. Sludges in Sets A, B, C and D were obtained from co-treatment of wastewater and 3%, 5%, 7% and 10% (v/v) leachate respectively. The highest Cr, Ni and Fe solubilization was obtained from Set A. Sulfur oxidizing bacteria were totally inhibited in Set D that received the highest volume of leachate.

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Heavy metal removal from wastewater using various adsorbents: a review

Journal of Water Reuse and Desalination ◽

10.2166/wrd.2016.104 ◽

2016 ◽

Vol 7 (4) ◽

pp. 387-419 ◽

Cited By ~ 98

Author(s):

Renu ◽

Madhu Agarwal ◽

K. Singh

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Aquatic Ecosystems ◽

Adsorption Process ◽

Metal Removal ◽

Low Cost ◽

Heavy Metal Removal ◽

Review Article ◽

Removal Capacity ◽

Removal Of Heavy Metals

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.

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Biological treatment of heavy metals in acid mine drainage using sulfate reducing bioreactors

Water Science & Technology ◽

10.2166/wst.2006.502 ◽

2006 ◽

Vol 54 (2) ◽

pp. 179-185 ◽

Cited By ~ 21

Author(s):

R. Sierra-Alvarez ◽

S. Karri ◽

S. Freeman ◽

J.A. Field

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Acid Mine Drainage ◽

Biological Treatment ◽

Mine Drainage ◽

Metal Removal ◽

Abandoned Mines ◽

Synthetic Wastewater ◽

Sulfate Reducing ◽

Acid Mine

The uncontrolled release of acid mine drainage (AMD) from abandoned mines and tailing piles threatens water resources in many sites worldwide. AMD introduces elevated concentrations of sulfate ions and dissolved heavy metals as well as high acidity levels to groundwater and receiving surface water. Anaerobic biological processes relying on the activity of sulfate reducing bacteria are being considered for the treatment of AMD and other heavy metal containing effluents. Biogenic sulfides form insoluble complexes with heavy metals resulting in their precipitation. The objective of this study was to investigate the remediation of AMD in sulfate reducing bioreactors inoculated with anaerobic granular sludge and fed with an influent containing ethanol. Biological treatment of an acidic (pH 4.0) synthetic AMD containing high concentrations of heavy metals (100 mg Cu2+l−1; 10 mg Ni2+l−1, 10 mg Zn2+l−1) increased the effluent pH level to 7.0–7.2 and resulted in metal removal efficiencies exceeding 99.2%. The highest metal precipitation rates attained for Cu, Ni and Zn averaged 92.5, 14.6 and 15.8 mg metal l−1 of reactor d−1. The results of this work demonstrate that an ethanol-fed sulfidogenic reactor was highly effective to remove heavy metal contamination and neutralized the acidity of the synthetic wastewater.

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Competitive adsorption and mechanism of hexahydroxy metallic system by aminated solution-blown polyacrylonitrile micro/nanofibers

Water Practice & Technology ◽

10.2166/wpt.2021.084 ◽

2021 ◽

Author(s):

Huiqing Lou ◽

Siyu Li ◽

Xiangwei Feng ◽

Xianzhong Cao

Keyword(s):

Heavy Metal ◽

Metal Ions ◽

Adsorption Capacity ◽

Metal Ion ◽

Metal Removal ◽

Interactive Effect ◽

Maximum Adsorption Capacity ◽

Coupling Mechanism ◽

Metal System ◽

Metallic System

Abstract Adsorptive properties for Cd(II), Cr(III), Cu(II), Ni(II), Pb(II) and Zn(II) onto an amidoxime-functionalized polyacrylonitrile (APAN) micro/nanofibers were systematically investigated in hexahydroxy metallic solution system using batch experiments. The interactive effect of multi-metal ions in multi- metal systems was antagonistic in nature, and the adsorption capacity in multi-metal system was lower than that in single-metal system. The Langmuir isotherm model could explain respectively the isotherm and kinetic experimental data for hexahydroxy metallic system with much satisfaction. The maximum adsorption capacity in hexahydroxy metallic for Cd(II), Cr(III), Cu(II), Ni(II), Pb(II) and Zn(II) was calculated to be 98 mg/L, 158 mg/L, 80 mg/L, 76, 312 and 58 mg/L individually. The APAN micro/nanofibers possessed good selectivity toward Pb(II) and Cr(III), over Cd(II), Cu(II), Ni(II), and Zn(II), having the highest selectivity coefficients at 17.52 and 6.07 in the test range. The five adsorption-desorption cycle experiments exhibited that APAN micro/nanofibers adsorbent are readily reusable, and have potential for heavy metal removal from wastewater. The adsorption behavior in multi-metal systems was shown to be complex, including surface complexation, antagonistic competition and displacement reactions. The diversity and selectivity in metal ion adsorption onto the micro/nanofibers relate mainly to the stability constants, and the microscopic coupling mechanism between the heavy metal ions and the functional groups on the fiber surface. This interaction mechanism between the favorable component and other metal ions could contribute significantly to the direct displacement impact illustrated schematically.

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Heavy Metal Removal from Aqueous Solution Using Biosurfactants Produced by Pseudomonas aeruginosa with Corn Oil as Substrate

Indonesian Journal of Chemistry ◽

10.22146/ijc.28805 ◽

2018 ◽

Vol 18 (3) ◽

pp. 472

Author(s):

Venty Suryanti ◽

Sri Hastuti ◽

Tutik Dwi Wahyuningsih ◽

Mudasir Mudasir ◽

Dian Kresnadipayana ◽

...

Keyword(s):

Aqueous Solution ◽

Heavy Metal ◽

Metal Ions ◽

Contact Time ◽

Metal Ion ◽

Metal Removal ◽

Corn Oil ◽

Metal Ion Removal ◽

Ion Removal ◽

Removal Capacity

The batch removal of Cu(II), Cd(II) and Pb(II) from individual heavy metal ion aqueous synthetic solution using biosurfactants produced by Pseudomonas aeruginosa with corn oil as substrate was investigated. The metal ion removal process of crude preparation biosurfactants (CPB) was established to be dependent on the initial pH and contact time. The optimum metal removal was observed at pH 6.0 of the initial metal solution and 10 min of contact time. The affinity sequence for metal ion removal was Pb(II)>Cd(II)>Cu(II). The removal capacity value of biosurfactant for Cu(II), Cd(II) and Pb(II) from single metal ions solution were 0.169, 0.276 and 0.323 mg/g, respectively. The removal capacity value of biosurfactant for Cu(II), Cd(II) and Pb(II) from multi metal ions solution were 0.064, 0.215 and 0.275 mg/g, respectively. The removal capacity of individual metal ion was diminished by the presence of other metal ions in multi metal ions from synthetic aqueous solution. The removal capacity value of biosurfactant for Cu(II), Cd(II) and Pb(II) from silver industry wastewater were 0.027, 0.055 and 0.291 mg/g, respectively. The results indicated that biosurfactants have potential to be used in the remediation of heavy metals in industrial wastewater.

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Insights into the Recent Use of Modified Adsorbents in Removing Heavy Metal Ions from Aqueous Solution

Biointerface Research in Applied Chemistry ◽

10.33263/briac122.18841898 ◽

2021 ◽

Vol 12 (2) ◽

pp. 1884-1898

Keyword(s):

Aqueous Solution ◽

Heavy Metal ◽

Metal Ions ◽

Metal Ion ◽

Heavy Metal Ions ◽

Metal Removal ◽

Low Cost ◽

Ion Concentration ◽

Future Research ◽

Batch Tests

Natural water gets contaminated with heavy metal ions because of industrial effluents' discharge into the aquatic environment. As these heavy metal ions cause various health hazards, they should be removed from the aqueous solution. Heavy metal ion concentration in the aqueous solution is very less, so conventional metal removal and recovery processes cannot be applied here. The adsorption method is a great alternative to all these processes as it is a cost-effective and easy method. The use of natural, low-cost materials as adsorbents is eco-friendly also. However, metal uptake capacity of low-cost materials is very less. So, modification is required for low-cost materials to increase their efficiency. In the present review, different modification procedures adopted by different researchers have been discussed. Different low-cost materials used are sawdust, fruit and vegetable wastes, soil, minerals, etc. The modifying agents are heat, acids, bases, and other chemicals. Nevertheless, most of the studies are limited to batch tests only. Future research should be carried out on the extension of batch tests to column study for the large-scale treatment of contaminated water, and the cost of modification procedures and their impact on the environment should also be assessed.

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pH-Regulated Carbon Dots Fluorescence Sensor Array Detection of Multiple Heavy Metal Ions Under Stepwise Prediction

10.21203/rs.3.rs-1170064/v1 ◽

2022 ◽

Author(s):

Zijun Xu ◽

Yuying Liu ◽

Jiao Chen ◽

Xiyuan Wang ◽

Hao Liu ◽

...

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Metal Ions ◽

Metal Ion ◽

Heavy Metal Ions ◽

Sensor Array ◽

Chelating Agent ◽

Fluorescence Sensor ◽

Array Detection ◽

Multiple Heavy Metals

Abstract As a large amount of heavy metals leaches into water sources from industrial effluents, heavy metal pollution has become an important factor affecting water quality. To enable the detection of multiple heavy metals, we constructed a pH-regulation fluorescence sensor array. Firstly, by adding a metal chelating agent as receptor, metal ions and carbon quantum dots (CDs) were connected to distinguish between Cr6+, Fe3+, Fe2+, and Hg2+ ions. Thus, the lack of affinity between the indicator functional groups and the analyte was solved. Secondly, by adjusting the pH environment of the solution system, an economical and simple array sensing platform is established, which effectively simplified the array construction. In this study, the SX-model was used in the field of fluorescence sensor array detection for metal ion recognition. Based on the strategy of stepwise prediction, combined with the classification and concentration models, the bottleneck of the unified model in previous studies was broken. This sensor array demonstrated sensitive detection of four heavy metal ions within a concentration range from 1 to 50 µM, with an accuracy of 95.45%. Moreover, it displayed the ability to efficiently identify binary mixed samples with an accuracy of 95.45%. Furthermore, metal ions in 15 real samples (lake water) were effectively discriminated with 100% accuracy. A chelating agent was used to improve the sensitivity of heavy metal ion detection and eventually led to high-precision prediction using the SX-model.

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