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The unorganized dumping of effluents along with different wastes directly into the water and soil has resulted in the rise of the concentration of many harmful metals, chemicals, and other gases in the environment. Widely known heavy metals triggering pollution issues are Lead (Pb), Chromium (Cr), Mercury (Hg), Cadmium (Cd), Copper (Cu), Arsenic (As) and Selenium (Se), as these heavy metals are generally found in the effluents of fertilizers, metallurgy, electroplating, and electronics industries. A number of physical-chemical reactions such as acid-base, oxidation-reducing, precipitation- dissolution, solubilization and ion-exchange processes occur and affect metal speciation. The physical methods used for heavy metals removal include magnetic separation, electrostatic separation, mechanical screening method, hydrodynamic classification, gravity concentration, flotation, and attrition scrubbing. The chemical methods used for eliminating heavy metals are chemical precipitation, coagulation and flocculation processes and the heavy metals are therefore removed as sludge. Electro-deposition, membrane filtration, electro-flotation and electrical oxidation are the various electrochemical treatment methods that are used to remove heavy metals from wastewater. Bioremediation is a biological method of eliminating toxins from the environment by using biological microbial bacteria such as Pseudomonas and Sphingomonas. Examples of bioremediation technologies include field farming, bioleaching, phytoremediation, bioventing, bioreactor, bio-stimulation and composting. Bioremediation is a natural process and is quite applicable as a waste treatment process for contaminated soils. The microbes present in the solution or soil can degrade the pollutants. It can also prove to be less expensive than other technologies that are used for clean-up of hazardous waste and are also useful for the destruction of a wide variety of contaminants as many hazardous compounds can be transformed into harmless products.

Background: Kraton/polyaniline ionomer is synthesized and further characterized by electrochemical studies to check the redox properties of the material. Ion exchange capacity, proton conductivity, and selectivity of the synthesized membrane were determined. And found that the membrane was selective for Cu (II) ions. Methods: The dry Kraton membranes were weighed and kept in 25 mL of 10 % prepared aniline solution in a conical flask for 5, 10, 15, and 20 minutes below 10 0C for socking. The prepared solution of 30 mL of 0.1 M potassium peroxydisulfate was added in a conical flask at constant stirring below 10 0C for half an hour. Finally, the aluminum foil-covered conical flask was kept in the refrigerator for 24 h and modified Kraton membranes were weighed again before carrying out further studies. Results: The membrane was characterized by some physicochemical methods like SEM, TGA, T-IR, IEC, proton conductivity and selectivity sorption studies. An ionomeric membrane of Kraton polymer was developed as reported earlier. Kraton membrane showed the IEC of 1.9 meq·g-1. The FTIR spectrum of Kraton/PANI film reveals that weight loss up to 400°C may be found because of the thermal degradation of composite substances. Conclusion: Ion-selective potentiometric was carried out using the self-prepared ion-selective membrane electrode. The membrane was prepared by solution casting method. The membrane was characterized by some physicochemical methods like SEM, TGA, T-IR, IEC, proton conductivity and selectivity sorption studies. On the basis of selectivity studies, the composite material was found selective for Cu (II) ion. A copper ISME was successfully fabricated using the solution casting method. The ISME possessed good selectivity, linearity, working pH range, and response time which was also used as an indicator electrode for the titration of copper using EDTA.

The FeZnO (iron zinc bimetallic oxide) was synthesised using the ultrasound-assisted method and further converted into FeZnOAC (iron zinc bimetallic oxide-doped activated carbon) by treating it with activated carbon. As developed FeZnOAC is effectively used for the adsorption of Fuchsine dye from an aqueous dye solution. A 200 mg of FeZnOAC was sufficient for the rapid removal of Fuchsine (>97.64%) dye. The kinetic adsorption data is well fitted with a pseudo-second-order model. The Langmuir isothermal model shows a high regression coefficient (R2) than the Freundlich with a Qmax of 333.33 mg g−1. The dye adsorption at varying temperatures (i.e. 298–318 K) was based on a multi-layered statistical physics model. The n value (n

Background: Nanoparticles have become an important part of many modern scientific technologies. Also, many naturally occurring nanoparticles play an important role in various natural and synthetic processes. The detection of these nanoparticles is expensive and challenging. This review paper explains in detail about various sensor-based methods used for the detection of nanoparticles. Methodology: Sensor-based analytical techniques are more accurate than other techniques. Nanoparticles may occur in air, water, solid surface and human or other living organisms’ physical environments. The detection methods include spectroscopic techniques, electrochemical methods, microcavities and microlasers based detection, optical techniques and many other highly sensitive methods. All these methods and their principles are explained in this study. The importance and the ill effects of the nanoparticles are explained in this article. Further, the detection of a particular single nanoparticle is also discussed. Conclusions: The detailed comparative analysis of these methods has shown that sensor-based methods are highly efficient for the detection of nanoparticles. Further research in this field may introduce many cost-effective and high efficient detection techniques that would revolutionize the medical and other application fields.

The prospective of this work is to synthesize a new nanocomposite that serves as an electrode material for the immobilization of biomolecules. In this work surface-functionalized single-walled carbon nanotubes (f–COOH–SWCNTs), and hydrothermally synthesized surface defected 2D nanoplates wrapped by polpyrrole matrix was developed. The developed nanocomposite was utilized as the anode material for the immobilization of enzymes. Nanocomposite f-SWCNTs@Ppy@NiMoSe2 was characterized by X-ray diffraction spectroscopy (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and the electrochemical methods including cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and linear sweep voltammetry (LSV). The electrochemically controlled bioanode reached to the open circuit potential (OCV) of 0.35 V and delivered the maximum current density of 9.01 mA cm−2 in 50 mM glucose concentration prepared in phosphate buffer solution (PBS) (pH 7.0) as the testing solution at 100 mVs−1 scan rates.

Fischer-Tropsch (FT) process has great potential to accomplish energy security but also for utilizing greenhouse gases to address the energy problem. Different kinds of feedstocks like coal, biomass (via gasification), CO2, methane (via reforming), and nonconventional energy sources are used to obtain the syn-gas (CO and H2). The formation of hydrocarbons in the FT process follows ASF distribution over the majority of the catalysts. It can be overcome by the application of a suitable catalyst, controlling the active metal interaction with the support and interaction of formed hydrocarbon with the support. The ratio of syn-gas is important to maintain the desired conversion and to have more selectivity towards C5+ products. Increase in the H2: CO ratios in the feed increases C5+ products and methane decreases. Whereas with the decrease in the ratios increases undesirable reactions and methane formation. In this article, we have discussed the recent literature from the viewpoint of increasing the C5+ selectivity. Support has a profound influence on product distribution. With the application of suitable support and controlling the interaction of the active sites yields the good CO conversion with fewer lighters and higher C5+ hydrocarbons.

Colorimetric and ratiometric fluorescent probe for cations gain very well attention by the chemist, biologist and environmentalist. Metals has two sides, first is biolgical active for living creature and toxic nature for the ecosystem. From last three decades the scientists are contiously trying to find out the best solution for the detection of cations at micro as well as nanomolar levels. In the present review we discussed the colorimetric and ratiometric fluorescent probe synthesized by the authors in almost half decade.

Enzymatic biofuel cells (EBFCs) produce electrical energy from green and renewable fuels, by utilizing redox enzyme. However, the main issue of low power output and stability of the electrode still prevails in this field. Extensive research is going on to overcome this problem by improving the electrical communication between the enzyme and the current collector. In the light of this, a new electrode design based on reduced graphene oxide (rGO) and functionalized magnetic nanoparticles (f-Fe3O4 NPs) in polyaniline matrix has been proposed and employed for the purpose of the EBFCs application, in order to achieve efficient electron shuttling between enzyme glucose oxidase (GOx) and the electrode surface. The as-prepared rGO/PANI/f-Fe3O4 nanocomposite was examined by analytical techniques viz, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and the electrochemical behaviour of the rGO/PANI/f-Fe3O4 nanocomposite and rGO/PANI/f-Fe3O4/Frt/GOx bioanode was determined by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and linear sweep voltammetry (LSV). The bioanode attained a maximum current density of 32.9 mA cm−2 at the optimum glucose concentration of 50 mM.

An estimated 2.2 billion people in 108 countries are expected to survive on multidimensional poverty and almost 1.5 billion out of 2.2 billion people survived on or less than US$1.25 a day. This review highlights the concept of a green economy that promotes an attractive green revolution to the present economic crises affecting developing countries for sustainable economic and environmental improvement. Green roads and highways can reduce the emissions released from fossil fuels and greenhouse gases if constructed with carbon neutral materials. Thus, carbon neutral materials used for the construction of green roads and highways can absorb temperature and excess emissions released by the vehicles because of their neutralities. This is because of the massive quantity of natural aggregates used during construction. Problems associated with green roads and highways made from carbon neutral materials are incompatibles with land use, geology, topography, substructure, landscape, rainfall, and other physical features. Therefore, physical features, geology, landscape, transportation, and development substructures were measured as crucial problems for national development. Most of the approaches used in this study are based on the context of a green economy and the development of green roads and highways. The USA possesses the highest GDP per capita of US$52,194.90 and Bangladesh possesses the lowest GDP per capita of US$1029.60. This implies that the GDP for USA is 50.70 times higher than that of Bangladesh. The study highlights positive solutions to the above global challenges. It can be concluded that global challenges will be addressed through the concept of green revolutions.

Poly(3,4-ethylene dioxythiophene): polystyrene sulfonate (PEDOT: PSS) zirconium(IV) phosphate (ZrP) based ionomeric membrane was prepared by a solution-casting method. Subsequently, aniline polymerization was carried out on the surface of the membrane by oxidative chemical polymerization. It was characterized by thermogravimetric analysis/differential thermal analysis/differential thermogravimetry (TGA/DTA/DTG), scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive X-ray (EDX) analysis, and Fourier-transform infrared (FTIR) spectroscopy. The membrane was also characterized by ion-exchange properties. The tip displacement investigation of the ionomeric membrane was also carried out. The outcomes demonstrated that the manufactured ionomeric membrane could produce generative strengths (tip powers), and consequently create good displacement. In this manner, the proposed ionomeric membrane was found proper for bending movement actuator that will give a successful and promising stage for smaller-scale mechanical applications.

Larger amount of poultry waste is generated in tonnes round the whole globe due to high-level demand for poultry meat. Therefore, there is a higher challenge involved in the management of agro-industrial wastes, especially poultry waste. There are numerous applications where feather could be utilized that entails feedstock, decorative applications, bedding materials, medical devices, dusters, and fertilizers. The conventional techniques such as landfilling and burning are not eco-friendly because it involves the discharges of several threat and hazards to the environment and to humans. Therefore, there is a need to search for an eco-friendly and sustainable techniques that can convert poultry waste into added-value products using biological means. Therefore, this chapter intends to provide a detailed information on the application of beneficial microorganism as one of the environmental and sustainable approaches that could be used for effective conversion of these poultry wastes, such as feathers, into value-added products like animal feeds, biofertilizers, and many more. The modes of action thorough which the poultry waste could be degraded were also highlighted.

In the past few decades, the scientific community have used aqueous solutions as the media for enzyme and whole cell biocatalysis reactions, but nonaqueous media also play a significant role in biocatalytic reactions, for example, in biotransformation technology. The design and discovery of efficient biocatalysis and has made tremendous progress for various synthetic applications in recent years. Versatile nonaqueous “green” solvents have been used in biocatalysis and are divided into three major solvent systems: ionic liquids (ILs), supercritical fluids (SCFs), and organic solvents. Recent works explain that enzymatic reactions in nonaqueous media offer new prospects for the production of useful chemicals such as surfactants, peptides and proteins, emulsifiers, wax, biopolymers, chiral drug molecules, etc. Compared with aqueous solvents, the feasibility of enzymatic reactions in nonaqueous solvents offers various potential aspects for biotechnological production. Biocatalysis also plays a key role in the production of various compounds with applications in the chemical and pharmaceutical industries. In this chapter, we will discuss biocatalytic reactions and the role of nonaqueous solvents.

Water borne polyurethanes have gained significant attention due to high-performance, excellent elasticity, no toxicity, abrasion resistance, adhesion functionality, flexibility, environmental friendliness, and broad substrate suitability. The physiochemical properties of water borne polyurethanes include low temperature, one component application, low viscosity, low solubility, and excellent coating performance. Therefore, this chapter intends to provide a detailed information sustainable production and applications of water borne polyurethanes. Different techniques such as thermal gravimetric analysis, Fourier transform infrared spectroscopy, mechanical measurements, and dynamic thermomechanical analysis used for the characterization of water borne polyurethanes were also highlighted. Moreover, detailed information on the application of water borne polyurethane plus polyurethane-urea dispersions for the production of novel eco-friendly nanomaterials were also highlighted.

In current research, solid-state materials are often used as the most promising materials for hydrogen storage materials in comparison of the other storage materials. Hydrogen is considered as an important source of energy storage system for automotive applications. Hydrogen as a conventional fuel offers high potential benefits due to their easily storage and transportation and considered as an alternative fuel because of its natural abundance and a clean and sustainable energy carrier. It is available in abundance and is the renewable sources of energy and, more significantly, is a clean fuel. Metal hydrides are able to store relatively large amounts of hydrogen in a solid phase as compared with other solid-state materials with safety and long-term stability. This perspective chapter highlights the brief idea about the various solid-state materials as storage of hydrogen and various applications in energy fields.

Graphene is a two-dimensional substance with a large monolayer sheet of sp2 hybridized carbon atoms and possessing a zero-gap and large surface area. It has unique optical, thermal, electronic, mechanical, and magnetic properties that fascinated the scientific community for its use as storage media in recent years. Due to these properties, graphene can be considered as extensive research materials in various fields such as fuel cells, photovoltaic cell, nanoelectronics, batteries, super-capacitors, sensing, gas sorption, catalysis, and separation and storage. Extraordinary and enormous applications of graphene are in the field of nanoelectronics, and fabrication of high-quality graphene is essential in large production. The large surface/volume ratio of these materials has significant features with respect to energy storage, and the opportunity of this new class of materials is used for hydrogen storage devices. Recent investigations have shown that these nanomaterials have been used as nanostructured systems viz., carbon nanotubes, complex hydride/carbon, nanocomposites, nanomagnesium based hydrides, boron nitride nanotubes, TiS2/MoS2 nanotubes, and polymer nanocomposites are considered as a hydrogen storage devices. In this chapter, we have discussed the contribution of chemically modified graphene-based materials and their applications in the field of hydrogen storage systems.

Over the years, there are numerous benefits derived from water borne polyurethane which entails medical devices (vascular prostheses, catheters, pacemakers), reconstructive surgery materials (breast implants, wound dressings, maxillofacial prosthetics, several other tissue implants) obstetrics and gynecology plus reproductive biology (contraceptive sponges, condoms, and assisted reproductive technology devices) medical materials (surgical drapes and hospital sheets). Also, they are extensively utilized in wound and plaster sectors because of the flexible, barrier protective, antimicrobial and soft properties. Therefore, this chapter intends to provide detailed information on the application of water borne polyurethane most especially in the medical field such as drug delivery with nanocapsules plus nanoparticles, bone regeneration, catheters polyurethane, contact lenses, tissue engineering scaffolds.