Remediation of noxious wastewater using nanohybrid adsorbent for preventing water pollution

Electrochemical oxidation and sensing of para benzoquinone using a novel SPE based disposable sensor

Para-benzoquinone (PBQ) is an emerging micro-contaminant owing to its chronic toxicity to plants and animals as well as its potential to induce cytotoxicity in primary rat hepatocytes and kidney cell injury. Hence, it is of utmost importance to monitor this contaminant in industrial wastewater and groundwater. In this article, we devised a unique disposable sensor that is based on a screen-printed electrode using MnO2@Co-Ni MOFs/fMWCNTs nanocomposite and is able to detect PBQ. The as-produced nanocomposite was prepared via ultrasonic assisted reflux condition and thoroughly examined by several physicochemical characterisation methods such as SEM, EDX, TEM, Raman, AFM, UV-visible, and FT-IR. Moreover, electrochemical methods like CV, DPV, EIS, and chronoamperometry were used for detecting PBQ on MnO2@Co-Ni MOFs/fMWCNTs/SPCE. Sensor performance has been investigated thoroughly and optimized to enhance the analytical potential of the fabricated sensor. DPV analysis was done on MnO2@Co-Ni MOFs/fMWCNTs that exhibit high selectivity, low peak potential, a broader linear detection range (0.005 mM-30 mM), and a LOD of 0.0027 ± 0.0005 mM. The designed electrode has shown remarkable reproducibility and excellent repeatability, with relative standard deviations of 0.12%, and 0.17%, respectively. Additionally, MnO2@Co-Ni MOFs/fMWCNTs/SPCE have been used to analyse PBQ in industrial wastewater samples, and the results have shown a significant level of recovery between 96.91 and 105.67%. Moreover, the PBQ sensor displays high applicability and was verified via the use of HPLC techniques. This disposable sensor is quick, easy, and cost-effective, so it can be useful in the future for analysing other phenolic contaminants present in environmental samples.

Biogenic polymer nanoparticles to remove hydrophobic organic contaminants from water

Soil and water pollution is of significant concern worldwide because of the consequences of environmental degradation and harmful effects on human health. Water bodies are very much polluted by various organic and inorganic pollutants by different human activities, including industrial wastes. Environmental pollution remains high because of urbanization-induced industrial developments and human lifestyle. It accumulates pollutants in the environment including plants and living organisms. Even mothers' milk is poisoned because of the uncontrolled, widespread increase in pollution. The discharge levels of organic hydrophobic contaminants in the water and soil are increasing rapidly. This severe pollution must be remediated to upgrade the environment and ensure the safety of human beings. It is vital to eradicate soil and water pollution to guarantee sufficient food and water. Different techniques available to remove the pollutants vary according to the type of pollutants. Hydrophobic contaminants are more dangerous than heavy metals and other pollutants; they cannot be easily removed, requiring special care. Hydrophobic organoxenobiotics released in the environment pose severe contamination in soil and water. Therefore, developing efficient and cost-effective processes is necessary to remove hydrophobic contaminants from soil and water. With nanoparticle-mediated remediation techniques, the green-synthesized nanoparticles exhibit improved performance. This review consolidates reports on the remediation techniques of hydrophobic contaminants, focusing on green-synthesized remediation agents. The very limited works on green synthesis of polymeric nanoparticles, particularly polyurethane-based materials for organic contaminants removal demand more attention in this area. PRACTITIONER POINTS: Consolidated the effects of hydrophobic organic and plastic contaminants on environment degradation. Summarized the advantages of green synthesized polymer nanoparticles for efficient removal of hydrophobic contaminants. Discussed the different sources of pollution and remediation techniques referring 112 research works.

Preparation of Chitosan/β-Cyclodextrin Composite Membrane and Its Adsorption Mechanism for Proteins

A significant portion of the protein in food waste will contaminate the water. The chitosan/modified β-cyclodextrin (CS/β-CDP) composite membranes were prepared for the adsorption of bovine serum albumin (BSA) in this work to solve the problem of poor adsorption protein performance and easy disintegration by a pure chitosan membrane. A thorough investigation was conducted into the effects of the preparation conditions (the mass ratio of CS and β-CDP, preparation temperature, and glutaraldehyde addition) and adsorption conditions (temperature and pH) on the created CS/β-CDP composite membrane. The physical and chemical properties of pure CS membrane and CS/β-CDP composite membrane were investigated. The results showed that CS/β-CDP composite membrane has better tensile strength, elongation at break, Young's modulus, contact angle properties, and lower swelling degree. The physicochemical and morphological attributes of composite membranes before and after the adsorption of BSA were characterized by SEM, FT-IR, and XRD. The results showed that the CS/β-CDP composite membrane adsorbed BSA by both physical and chemical mechanisms, and the adsorption isotherm, kinetics, and thermodynamic experiments further confirmed its adsorption mechanism. As a result, the CS/β-CDP composite membrane of absorbing BSA was successfully fabricated, demonstrating the potential application prospect in environmental protection.

Effect of the green synthesis of CuO plate-like nanoparticles on their photodegradation and antibacterial activities

Green synthesis of copper oxide nanoparticles and its effects on photocatalytic dye degradation and antibacterial activities are reported. The synthesis of nanoparticles by green routes provides many advantages over chemical routes, including simplicity, cost-effectiveness, and fast processing route without using any costly or harmful chemicals. Tridax procumbense (coat buttons) plant root extract was used to synthesize copper oxide nanoparticles. The synthesized Tridax procumbense-copper oxide nanoparticles (TP-CuO NPs) were characterized by UV-visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), dynamic light scattering spectroscopy (DLS), and X-ray diffraction (XRD) techniques. The synthesized TP-CuO NPs were applied for photocatalytic dye degradation and antibacterial activity studies. The TP-CuO NPs exhibited a maximum antibacterial activity at 500 μg mL^-1 concentration against Staphylococcus aureus and E. coli showing inhibition zones of 7.5 mm and 7.2 mm, respectively. The photocatalytic ability of the TP-CuO was also tested against the textile dye Trypan blue (TB), and showed about 55% degradation after 48 h for 500 μg mL^-1 CuO NP concentration, showing a concentration-dependent degradation efficiency. This is the first work on TP-derived CuO nanoparticles and their photocatalytic and antimicrobial applications. Overall, this study supports the superiority of green-synthesized TP-CuO NPs as photocatalytic and antimicrobial agents.