Metal Pollutants In Wastewater Research Articles

Fabrication polyaniline via electrochemical synthesis for highly efficient removal of Cr(VI)

AbstractPolyaniline (PANI) is recognized for its exceptional electrochemical conductivity, and its chemical structure, rich in amino and imine functional groups, exhibits significant removal capabilities for heavy metal pollutants in wastewater. In this study, PANI was synthesized via electrochemical cyclic voltammetry, and its micromorphology and phase structure were characterized using SEM, TEM, FTIR, and XRD. By modulating the polymerization potential, control over the surface morphology was achieved, thereby optimizing its adsorption performance. Additionally, the adsorption efficiency of electrochemically synthesized PANI for Cr(VI) in wastewater was assessed. Notably, in acidic conditions, PANI demonstrated an exceptionally high adsorption capacity for Cr(VI), reaching 130.1 mg/g. These findings highlight the potential of conductive polymers such as PANI in the development of highly efficient adsorbents for wastewater treatment, providing tangible solutions for addressing water pollution.

Photoresponse of Ti3C2Tx MXene promotes its adsorptive-reductive removal of Cr(VI) from water

MXenes, such as Ti3C2Tx, demonstrate tremendous potential as heavy metal adsorbents due to their abundant reaction sites, high hydrophilicity, controllable interlayer spacing, and inherent reduction ability. However, their structural dependent pollutant removal performances and the related mechanisms are far less studied. Therefore, the removing abilities of Cr(VI) from water on Ti3C2Tx MXenes with different structures (multilayer (ML-) and delaminated (DL-) Ti3C2Tx) synthesized via several etching techniques were evaluated. Focusing on the most effective ML- and DL-Ti3C2Tx obtained by acid/fluoride salt etching, the impacts of structural variations on the Cr(VI) removal performances were explored. Both ML- and DL-Ti3C2Tx demonstrate outstanding Cr(VI) adsorption and reduction capabilities, achieving equilibrium within 500 min with capacities of 92.7 and 205 mg/g, respectively. The differences in removal mechanisms stemed from the varying adsorption and reduction capacities of two MXenes. ML-Ti3C2Tx, with lower surface area and porosity, had low adsorption capacity but superior reduction ability, efficiently converting most Cr(VI) to Cr(III) (66.8%). Conversely, DL-Ti3C2Tx exhibited better removal efficiency but a lower capacity for reduction (45.7%). Notably, although the partial reduction of DL-Ti3C2Tx to TiO2 results in its limited chemical reduction capacity, Ti3C2Tx might serve as a co-catalyst for TiO2, boosting the photoresponsiveness of DL-Ti3C2Tx or TiO2 through Ti3C2Tx/TiO2 heterojunctions, thereby facilitating photocatalysis to realize the reduction of Cr(VI). Both Ti3C2Tx exhibited both excellent Cr(VI) removal capacity and detoxification capacity, demonstrating their high potential in treating heavy metal pollutants in wastewater.

Evaluating the Potential of Modified Mango Leaves as a Biosorbent for the Removal of Mercury (II) Ion and Congo Red from Wastewater

The discharge of harmful metallic elements from industrial byproducts has resulted in notable environmental and public health risks. The aim of this study was to investigate the effectiveness of mango leaves as a cost-effective adsorbent in eliminating Hg (II) ions from industrial effluents. Experimental procedures were carried out under controlled conditions at ambient temperature to evaluate the influence of pH, contact duration, initial metal levels, adsorbent quantity, and temperature on the adsorption mechanism. The most favorable pH for optimal Hg (II) ions adsorption was identified at pH 7. The adsorption process displayed swift kinetics in the initial 30 minutes of contact, leading to a removal rate exceeding 90%, with equilibrium achieved after 70 minutes of stirring. Analysis of kinetics revealed a significant correlation coefficient for a pseudo-second-order kinetic equation. The absorption of Hg (II) ions escalated with increased stirring intensity and decreased adsorbent amount. The interaction between Hg (II) ions, Congo red, and mango leaves was analyzed employing Langmuir, Freundlich, and BET isotherm models. The equilibrium data was best fitted by the Langmuir model, presenting a correlation coefficient of 0.98 and a maximum adsorption capacity of 28.40 mg/g. These results underscore the potential of mango leaves as an affordable bio adsorbent for addressing heavy metal pollution in wastewater.

Eco-friendly synthesis and application of NH2-COOH functionalized Fe3O4@graphite carbon microballs in heavy metal removal

Heavy metal pollution in wastewater is quite challenging for the environment. This study pioneers the synthesis of a novel adsorbent, amine-acid functionalized Fe3O4 decorated carbon micro-balls (NH2-COOH/Fe3O4@CMBs) via hydrothermal process and controlled thermal treatment under nitrogen atmosphere, utilizing eco-friendly resource glucose as a carbon precursor. The formation of cubic Fe3O4 nanoparticles and crystalline graphite within a carbon core-shell structure is confirmed. NH2-COOH/Fe3O4@CMBs show a porosity conducive to ion exchange in the range of 100–300 nm via FE-SEM, exhibiting a significant surface area of 494 m²/g with optimal pore volume. Within the carbon matrix, H2-TPR affirms the robust integration of Fe3O4, essential for high adsorption rates. In practical applications, NH2-COOH/Fe3O4@CMBs demonstrate exceptional performance, removing ∼ 99 % of Pb2+ ions in 30 min., showcasing an impressive adsorption capacity of 360 mg/g. The rapid and potent adsorption is attributed to the electron-rich graphite layers and the presence of abundant chelating sites. This research introduces NH2-COOH/Fe3O4@CMBs as a commercially viable and environmentally responsible solution for the removal of hazardous heavy metals from wastewater. Scientific understanding of adsorptive material not only advances but also offers a tangible approach to mitigate a pressing public health concern, marking a significant stride towards sustainable water treatment technologies.

Tracking of the conversion and transformation pathways of dissolved organic matter in sludge hydrothermal liquids during Cr(VI) reduction using FT-ICR MS

In this study, the remediation effects of two types of sludge (ferric-based flocculant and non-ferric-based flocculant) on Cr(VI)-polluted wastewater were evaluated to clarify the key components in sludge hydrothermal solutions responsible for reducing Cr(VI) and understand the underlying molecular-level transformation mechanisms. The results revealed that the primary reactions during the hydrothermal processes were deamination and decarboxylation reactions. Correlation analysis highlighted proteins, reducing sugars, amino groups, and phenolic hydroxyl groups as the major contributors. In-depth analysis of the transformation process of functional groups within dissolved organic matter (DOM) and synergistic redox process between Cr(VI) and DOM in hydrothermal solutions demonstrated that phenolic hydroxyl and amino groups gradually underwent oxidation during reduction of Cr(VI) by DOM, forming aldehyde and carboxyl groups, among the others. Time-dependent density functional theory calculations revealed notable shift of reducing functional groups from ground state to excited state following iron complexation, ultimately facilitating reduction reaction. Subsequent investigations, including soil column leaching and seed germination rate tests, indicated that synergistic redox interaction between Cr(VI) and DOM significantly reduced waterborne heavy metal and toxic organic pollution. These findings carry substantial implications for sludge treatment and remediation of heavy metal pollution in wastewater, offering valuable insights into effective environmental remediation strategies.

Preparation of basic magnesium carbonate nanosheets modified pumice and its adsorption of heavy metals.

Heavy metal pollution in wastewater poses a grave danger to the environment and the human body. Pumice is a mineral with abundant reserves and low prices, and its prospect of heavy metal adsorbent is very broad. In this work, we modified pumice with basic magnesium carbonate nanosheets by a convenient hydrothermal synthesis. The adsorption capacity of heavy metals is greatly improved. The effects of different pH and adsorption dosages are investigated. All the optimum pH values for Cu2+, Pb2+, and Cd2+ are 5. The adsorption of three kinds of ions conforms to the quasi-second-order adsorption kinetics model. The theoretical adsorption capacities of Cu2+, Pb2+, and Cd2+, which are calculated by the Langmuir model, are 235.29mg/L, 595.24mg/L, and 370.34mg/L, respectively. The adsorption of Cu2+ and Cd2+ fit the Langmuir model better. The Freundlich model is fitted well with the adsorption of Pb2+. In the experiment simulating real wastewater, the adsorption capacity of heavy metals is not affected. It also shows good reusability in three regeneration cycles. And Mg5(CO3)4(OH)2·4H2O@pumice adsorption column showed the good removal efficiency of three heavy metals at different concentrations and different spatial velocities in the column experiment. Thus, it is believed that the Mg5(CO3)4(OH)2·4H2O@pumice is a promising adsorbent for the efficient removal of heavy metals.

Fabrication, Modification, and Mechanism of Nanofiltration Membranes for the Removal of Heavy Metal Ions from Wastewater

AbstractHeavy metals present in wastewater and water scarcity are a global challenge worldwide. The elimination of heavy metals in wastewater is necessary to protect the ecosystem and human health. Heavy metals such as lead, cadmium, and mercury are among many other toxic heavy metals present in wastewater. There are several conventional methods that have been implemented to mitigate heavy metal pollution in wastewater and according to literature, it has been evident that the nanofiltration (NF) separation technique requires minimal pressure to obtain high rejections of multivalent inorganic salts compared to conventional methods. NF separation process is highly competitive in terms of selectivity and cost‐benefit. The growing research trend of NF fabrication and modification collates that the technology has been applied in various industrial and municipality wastewater treatment facilities. The review paper aims to illustrate the health impacts of heavy metal exposure, the cons of conventional methods and the utilization of NF membranes in wastewater treatment, the overall factors affecting membrane performance, and future aspects of the separation techniques.

Substantial and efficient adsorption of heavy metal ions based on protein and polyvinyl alcohol nanofibers by electrospinning

The adverse effects of heavy metal pollutants in wastewater have threatened human health in recent decades. Therefore, the development of absorbents for such pollutants is essential to overcome these problems. Electrospun nanofibers are often used for wastewater treatment owing to their high porosity and high specific surface area. Zein from plants and collagen from animals are vulnerable to moisture, which limits its broad application in practice. However fully biodegradable polyvinyl alcohol (PVA), which is soluble in water, can be mixed with protein individually to overcome the limitation. In this work, the two proteins described above and PVA were combined to prepare protein nanofibers by electrospinning technology, which could achieve adsorption of Cu2+. As the protein content increased, the adsorption properties of the obtained nanofibers for Cu2+ showed a rising and then decreasing trend, with the highest point at 50 % of protein content, especially the collagen nanofibers, which reached 24.62 mg/g. Both protein nanofibers reached adsorption equilibrium after 15 h, but overall, collagen nanofibers showed a superior adsorption performance for Cu2+ than that by zein nanofibers. In the process of Cu2+ adsorption by protein nanofibers, both physical and chemical effect existed, and the physical effect played the leading role.

Biosorption Potential of Desmodesmus sp. for the Sequestration of Cadmium and Lead from Contaminated Water

Industrialization, urbanization, and natural processes have potentially accelerated the pace and level of heavy metals in the aquatic environment. Recently, modern strategies for heavy metal treatment in wastewater have received the specific attention of the scientific community. The present study aimed to assess the amorphous biomass of Desmodesmus sp. as a low-cost adsorbent to remove the cadmium (Cd) and lead (Pb) from aqueous solutions. It involved the optimization of pH, contact time, initial concentration of metal ions, and the dosage of biosorbent. Data collation revealed that an optimum contact time for both metals was 60 min, with an adsorption capacity of 63% for Cd and 66% for Pb. Different models were applied to the equilibrium data. The pseudo 2nd order described the best adsorption of Cd and Pb. The equilibrium data were computed with various isotherms. Langmuir isotherms better suit the adsorption of the above-mentioned metals. Hence, the maximum adsorption capacity of Desmodesmus sp. for Cd and Pb was 64.1 and 62.5 mg/g, respectively. The mechanism of biosorption was validated through a comparative FT-IR and Scanning Electron Microscopy of raw and metal-loaded algal biomass based on cell morphological changes. In order to study the reusability of adsorbent, adsorption-desorption of Cd and Pb ions was repeated three times using HCl. These results did not noticeably change in adsorption capacity during the three cycles. Using HCl (0.1 M), desorption of both metals was achieved up to 90% in three cycles. This work presented a long-term bioremediation approach for heavy metal pollutants in wastewater. This research could be seen as an interdisciplinary approach to large-scale heavy metal remediation. In addition, growing microalgae in wastewater produces animal feed and biodiesel. When compared to other conventional methods for environmental remediation and the manufacture of valuable products, the use of microalgae is a more efficient and cost-effective method.

Ultraviolet Radiation-Assisted Preparation of a Novel Biomass Fiber to Remove Cadmium from Wastewater

The heavy metal adsorbents developed based on biomass resources have valuable application prospects due to the characteristics of rich sources, renewability and low cost. In the present work, a carboxyl functioned loofah fiber (LF@AA) was synthesized via UV-induced polymerization, and its adsorption capacity for cadmium (Cd2+) was investigated systematically. This modification resulted in the effective combination of a loofah fiber template and polyacrylic acid (PAA), which promoted its adsorption of Cd2+ to significantly increase to 339.3 mg·g−1, and the applicable pH range was 4.0~7.0. Furthermore, the adsorbability of LF@AA remained stable at a high level after eight consecutive cycles. The adsorption kinetics and isotherm parameters revealed that the adsorption characteristics of cadmium conformed to the Weber–Morris and pseudo-second-order kinetics equations, and the adsorption process of cadmium conformed to Redlich–Peterson and Langmuir models. In addition, consequences of EDS, FTIR, and Zeta potential analysis reflected that the main adsorption mechanism should be ion exchange. Cd2+ was drawn to the adsorbent surface by electrostatic binding, and ion exchange occurred to form a bidentate chelate. This study suggests that it is reasonable and feasible to use natural biomass materials to develop efficient adsorbents to treat heavy metal pollution in wastewater.

Porous organic polymers as a promising platform for efficient capture of heavy metal pollutants in wastewater

Heavy metal pollution in aquatic systems is a tremendous threat to the environment and human beings. Porous organic polymers (POPs) as efficient and promising adsorbents have great potential for use in the metal removal from wastewater.

Highly selective capacitive adsorption and rapid desorption of arsenic ions in wastewater achieving by a recyclable urchin-like iron-manganese composite electrode

The demand for environmental protection drives researchers to develop new concepts or technologies to solve the problem of heavy metal pollution in wastewater. Herein, we report recyclable CDI electrodes composed of sea urchin-like iron-manganese composites to explore the capacitive adsorption and selective adsorption effects of arsenic ions in the simulated wastewater. Under the operating conditions of 1 mm electrode spacing and 1.2 V voltage, the maximum saturated adsorption capacity of the composite electrode for arsenic ions reached 411.22 mg/g, and when the initial concentration was 20 mg/L, the removal rate of arsenic ions reached 99.7%. Besides, the composite material also showed an excellent selective adsorption capacity under the coexistence of lead and cadmium ions. Finally, this recyclable composite electrode was capable of rapid desorption and can retain 97% of the initial capacity after fifty cycles of adsorption/desorption.

An investigation into the efficiency of microalgal dynamic membrane photobioreactor in nickel removal from synthesized vegetable oil industry wastewater: A water energy nexus case study

With growing concerns toward heavy metal pollution in wastewater due to their negative effects on human health and also the environment, a lot of effort has been put to find some novel and efficient methods in order to reduce or eliminate such hazardous elements. Chlorella vulgaris microalgae has been successful in heavy metal removal hence, the current study tries to develop an effective nickel removal technique using the combination of membrane separation along with microalgae dynamic membrane (DM) plus Chlorella vulgaris suspension in order to treat the synthetic vegetable oil wastewater. The experiments were divided into three phases. First phase was to comprehend the effect of microalgae's dry weight (DW) on nickel removal efficiency. With nickel's initial concentration being 10 mg. L−1, the results indicated that by tripling the concentration of microalgae, the removal efficiency increases by more than 66% within the first hour of treatment. There was no significance increase in treatment efficiency by increasing the treatment time from 1 h to 24 h. In phase 2, by initializing the nickel concentration to 10,12.5,17.5 and 20 mg. L−1, the experiments were done in a continuous mode inside a DM bioreactor (DMBR) after the microalgae DM was formed, which led to nickel's removal efficiency being reduced from 60% of previous phase to 22% after 1 h. In the third and last phase, fluidized microalgae inside a photobioreactor (PBR) plus micro-algae DM (DMPBR) were put in use. Comparing the results of this phase with last two phases, this phase with 72% removal compared to 63.6, 52 of previous phases, had the best results yet. To conclude, forming a dynamic membrane, not only preserves the primary membrane but also enhances the heavy metal removal efficiency.

The Adsorption of Corn Stalk Biochar for Pb and Cd: Preparation, Characterization, and Batch Adsorption Study

Biochar adsorption emerges as a convenient and cheap treatment technology to cope with the metal pollution in wastewater. In this study, a biochar made from corn stalks was prepared and its adsorption characteristics for two heavy metals, Pb and Cd, were investigated by materials characterization and batch experiments. Biochar pyrolyzed from waste corn stalks at 400–600 °C, where biochar prepared at 600 °C (BC600) was used to perform following experiments. In materials characterization, the SEM images were initially used to reveal an obvious porous structure feature of corn stalk biochar, followed by XPS and FT-IR analyses unraveling the effects of functional groups in adsorption, especially for phenol and carboxyl groups. These functional groups provided vital adsorption sites. In batch experiment, batch experiments were conducted under different factors such as pH, temperature, and background ionic strength. The increase of pH and temperature can improve the adsorption capacity, whereas the ionic strength showed negative effects. The adsorption processes of both metals can be interpreted by fitting pseudo-first order model, as indicated in kinetic experiments, and the adsorption isotherm can be well described by the Langmuir model. Overall, this study revealed the characteristics of corn stalk biochar and deciphered the potential adsorption mechanisms.

Preparation and characterization of magnetic modified bone charcoal for removing Cu2+ ions from industrial and mining wastewater

Heavy metal water pollution is an urgent global problem to be addressed. Copper ions are common toxic heavy metal pollutants in wastewater. In order to remove the excessive copper ions in wastewater, in this study, chicken bone charcoal was modified by sodium dodecyl sulfonate and combined with magnetic nanoparticles prepared with ferric chloride hexahydrate and ferrous sulfate heptahydrate to produce a high efficiency adsorbent. The characterization of the magnetically modified bone charcoal was analyzed by scanning electron microscopy, surface and porosity analyses, FTIR and thermogravimetric analysis. The optimal adsorption conditions of magnetically modified bone charcoal for Cu2+ were obtained through batch experiments. The highest removal rate and adsorption capacity of Cu2+ was 99.98% and 15.057 mg/g, respectively, when the pH was 3.0, adsorbent dosage was 0.2 g, initial concentration of the Cu2+ solution was 50 mg/L, and temperature was 25 °C. The adsorption process fitted well with the Langmuir isotherm and the pseudo-second-order kinetic model. The regeneration experiment indicated that M-SDS-BC-500 maintained a high removal rate after five repetitions. The results suggest that the adsorbent has wide application prospects.

Enhanced tolerance and resistance characteristics of Scenedesmus obliquus FACHB-12 with K3 carrier in cadmium polluted water

Microalgae have been recognized as a cost-effective biosorbent for heavy metal pollutants in wastewater, while microalgal biofilms exhibit significant potential in microalgae–water separation post-treatment. In this study, cadmium (II) removal mechanisms of suspended Scenedesmus obliquus FACHB-12 (isolated from southern China) and Scenedesmus obliquus biofilm with K3 carriers were investigated based on their cadmium removal efficiency, pigment content, and antioxidant activity. Scenedesmus obliquus biofilm achieved the highest cadmium (II) removal of 91.27% under 20 mg/L of cadmium stress compared to 87.49% by suspended Scenedesmus obliquus after three days. Under 10 mg/L of cadmium stress, photosynthetic pigments, extracellular polymeric substances, total protein, and antioxidant responses including superoxide dismutase, catalase, and glutathione were measured for both suspended and biofilm forms of Scenedesmus obliquus. During the cultivation process with cadmium solution, temporary inhibition of pigments was observed within the first 24 h and then recovered after two days of exposure to cadmium. Extracellular polymeric substance concentration increased significantly in the biofilm at 34.91 mg/g on the third day of exposure to 10 mg/L of cadmium compared to 22.52 mg/g for suspended Scenedesmus obliquus. Protein levels in both groups increased over time at similar concentrations at the end of the experiment. Antioxidant activity was enhanced during the absorption process, with higher activity observed in the biofilm group. The results suggested that Scenedesmus obliquus biofilm could provide higher cadmium removal efficiency with increased tolerance to cadmium content. This study provides insightful information on the response mechanism of Scenedesmus biofilms under heavy metal oxidative stress.

Effectiveness of a biogenic composite derived from cattle horn core/iron nanoparticles via wet chemical impregnation for cadmium (II) removal in aqueous solution

The objective of the current study was focused on the potential adsorption capability of a biogenic hydroxyapatite/iron nanoparticles-based composite tailored for the elimination of toxic pollutant, Cd(II) ions. Morphological along with physicochemical properties of composites were analyzed by different techniques including Scanning electron microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDAX), X-ray diffraction (XRD), and Fourier Transform Infrared Spectroscopy (FTIR). It has been noticed an increase in cell parameters of prepared composites with an increase in the amount of nanoparticles. The best adsorbent was found to be the one with a 5% amount of nanoparticles (P400Fe(5%)). The kinetics studies have shown that the pseudo-first-order-models were in good agreement for the removal of Cd(II) ions onto P400Fe(5%) at any concentration, suggesting a physisorption mechanism. Besides, isotherms analysis has consistently revealed Freundlich as the model better explained the isotherm data, with a maximum removal capacity of 392.3 mg g−1, higher compared to many adsorbents. Thermodynamically, the removal adsorption process of Cd(II) ions onto the composite favorable, exothermic, and spontaneous. The regeneration study has been also investigated with reusability used until four cycles. The overall results pointed out the suitability and efficiency of the prepared biogenic composite for the elimination of metal pollutants in wastewater.

Polymer Ligands Derived from Jute Fiber for Heavy Metal Removal from Electroplating Wastewater.

Industrial operations, domestic and agricultural activities worldwide have had major problems with various contaminants caused by environmental pollution. Heavy metal pollution in wastewater also a prominent issue; therefore, a well built and economical treatment technology is demanded for pollution-free wastewater. The present work emphasized pure cellulose extracted from jute fiber and further modification was performed by a free radical grafting reaction, which resulted in poly(methyl acrylate) (PMA)-grafted cellulose and poly(acrylonitrile)-grafted cellulose. Subsequently, poly(hydroxamic acid) and poly(amidoxime) ligands were prepared from the PMA-grafted cellulose and PAN-grafted cellulose, respectively. An adsorption study was performed using the desired ligands with heavy metals such as copper, cobalt, chromium and nickel ions. The binding capacity (qe) with copper ions for poly(hydroxamic acid) is 352 mg g−1 whereas qe for poly(amidoxime) ligand it was exhibited as 310 mg g−1. Other metal ions (chromium, cobalt and nickel) show significance binding properties at pH 6. The Langmuir and Freundlich isotherm study was also performed. The Freundlich isotherm model showed good correlation coefficients for all metal ions, indicating that multiple-layers adsorption was occurred by the polymer ligands. The reusability was evaluated and the adsorbents can be reused for 7 cycles without significant loss of removal performance. Both ligands showed outstanding metals removal capacity from the industrial wastewater as such 98% of copper can be removed from electroplating wastewater and other metals (cobalt, chromium, nickel and lead) can also be removed up to 90%.

Microbacterium sp. MRS-1, a potential bacterium for cobalt reduction and synthesis of less/non-toxic cobalt oxide nanoparticles (Co3O4)

BackgroundDetoxification of heavy metal pollutants in wastewater has become a serious problem to surrounding environment. This research was conducted to utilize a potential heavy metal-resistant bacterium for the remediation of cobalt metal and simultaneous synthesis of cobalt oxide nanoparticles in the form of powder for various industrial applications. Metal oxide nanoparticles have great applications in electrochemical devices such as supercapacitors, biosensors, and batteries.MethodA heavy metal-resistant bacterium Microbacterium sp. MRS-1 isolated from electroplating industrial effluent reduced cobalt ions from an initial concentration of 200 mg/L to 26 mg/L were analyzed by atomic absorption spectroscopy. Instrumental analysis of bacterially synthesized Co3O4 has been characterized. Cytotoxicity of synthesized nanoparticles was assessed by MTT assay.ResultsMicrobacterium sp. MRS-1 isolated from electroplating industrial effluent was found to be suitable for cobalt oxide nanoparticles as it showed tolerance towards high concentration of metal. The nutrient broth containing metal solution and Microbacterium sp. MRS-1 showed color change from light pink to dark pink indicated the formation of extracellular nanoparticles. It also converted soluble cobalt salts into less soluble cobalt oxide nanoparticles outside the cell which allows easy recovery of nanoparticles without the destruction of cells and simultaneous detoxification of toxic metal ions. Electron microscopic imaging verified that nanoparticles were predominantly surrounding the bacterial cells and SEM imaging revealed that the produced particles were in the range of 10–100 nm in size. XRD spectrum exhibited 2θ values were corresponding to cubic face-centered cobalt oxide (Co3O4) nanoparticles.ConclusionThe present study investigated new prospective for eco-friendly detoxification of toxic heavy metal Co from metal-polluted sites and the production of cobalt oxide nanoparticles in powder form for clinical and other industrial applications.

Treatment of Common Effluent Treatment Plant Pollutant under Growing & Non-growing Condition of Biomass

Heavy metal pollution in wastewater has always been a serious environmental problem because heavy metals are not biodegradable and can be accumulated in living tissues. Copper is widely used in various important industrial applications. The increasing level of heavy metals in the aquatic system due to incomplete treatment of industrial wastewater by existing conventional methods is of environmental concern. Therefore, there has been an increasing interest in the possibility of using biological treatments. It is important to evaluate the performance of biomass with actual industrial effluent to ensure its field applicability. Hence the experiments were conducted with actual industrial effluents collected from Effluent Treatment Plant (ETP) and tannery industry.