Titania-based photocatalytic degradation is extensively used for treating industrial wastewater containing textile dyes and phenol. In this study, manganese (Mn) (x = 1, 3, and 5 wt.%) and sulfur (S) (y = 1 wt.%) co-doped TiO2 (MnxSyT) were synthesized via sol-gel technique and characterized by X-ray diffraction (XRD), UV-visible DRS, PL, Brunauer-Emmett-Teller (BET), Fourier Transform Infrared (FT-IR), and SEM. The XRD showed that co-doping reduced the crystallite size to 13.77 nm while retaining the anatase phase. UV-visible DRS and PL showed that the co-dopant's synergetic effect reduced the TiO2 bandgap to 2.04 eV and improved electron-hole pair separation, enhancing the photodegradation efficiency. The BET showed the co-doping enhanced surface area (53-110 m(2)g(-1)) and pore volume (0.34-1.10 cm(3)g(-1)). FT-IR confirmed the photocatalysts' purity and stability, while SEM displayed better morphology and bulk superficial properties of the samples. Notably, Mn5S1T possesses low crystallite size and bandgap, high surface area, porosity and purity, better texture, and reusability, and achieving 59%, 86%, and 99% degradation of phenol, Yellow 2 G, and Blue KBR dyes, respectively, under optimized conditions (catalyst dose: 0.2 g/L, pollutant concentration: 20 ppm, pH: 3 (phenol) and 7 (dyes), irradiation time: 120 min) under sunlight. The pseudo-order (zero, first, and second) and BMG kinetics models are used to study the photodegradation of phenol and dyes. The analysis shows that the process follows first-order kinetics, with rate constants of 0.0066, 0.0087, and 0.0167 min(-)(1) for phenol, Yellow 2 G, and Blue KBR. Mn5S1T photocatalyst offers a cost-effective, efficient, and eco-friendly solution to degrade textile dyes and phenol on an industrial scale.

Different composition of mixed matrix membranes comprising Polyvinylidene fluoride (PVDF) as base polymer, Polyvinylpyrrolidone and Montmorillonite clay as additive was fabricated by phase inversion technique using N, N-Dimethylacetamide as a solvent. Furnished membrane samples were characterized by X-Ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), Thermal Gravimetric Analysis (TGA) and Scanning Electron Microscopy (SEM) for phase identification, functional group analysis, thermal stability, determination of surface morphology and textural features which show that PVP and MMT successfully modified PVDF membrane and resulted in PVDF/PVP/MMT mixed matrix membrane. Different membrane characteristics such as pure water flux, water content, porosity, shrinkage ratio, fouling recovery ratio and solute rejection were studied and calculated. The contemporary membrane (PPM5) having 5 wt. % of MMT represented the increase in pure water flux, porosity, and fouling recovery ratio from 13.8 Lm(-2)h(-1), 33% and 52% to 19.8 Lm-2h(-1), 85%, and 87%, respectively. The PPM5 also shows a reduction in shrinkage ratio from 19% to 7% and improved hydrophilicity which results in a solute rejection factor of 83% and 87% for Pb(II) and Cd(II), respectively, in comparison to other fabricated membranes. These membranes provide an economical and effective solution for wastewater treatment.

The undoped TiO2 (T), 1% Ni-doped TiO2 (N1T), and 1% Co-1% Ni co-doped TiO2 (C1N1T) photocatalysts were prepared by the sol-gel technique. The characterization of prepared materials was carried out by X-ray diffraction, Diffused Reflectance Spectroscopy, Scanning Electron Microscopy, Fourier Transform Infrared Spectroscopy, Brunauer-Emmett-Teller and Thermogravimetric Analysis to analyze composition, phase, morphology, and optical properties. These results revealed that C1N1T exhibited higher surface area, better pore volume and enhanced optical properties as compared to undoped and Ni-doped TiO2. Furthermore, the photoactivity of C1N1T nanoparticles was manifested toward Acetaminophen, Phenol and reactive dyes i.e., Remazol Black B and Yellow 2 G. Moreover, C1N1T nanoparticles showed remarkable degradation efficiency of 53%, 56%, 98% and 89% for Acetaminophen, Phenol and anionic dyes, i.e. Remazol Black B and Yellow 2 G under optimized conditions (pollutant concentration = 20 ppm; time = 120 min; C1N1T loading = 20 mg; irradiation source = solar light; pH = 4 for each dye, pH = 7 for phenol and pH = 9 for acetaminophen). The significant degradation values suggested that the C1N1T photocatalyst can be effectively employed to degrade the textile dyes and PPCPs from industrial wastewater.

The TiO2/AC nanosorbent was prepared via the impregnation method. The prepared material was characterised by using X-ray diffraction (XRD), Fourier transform Infra-Red (FT-IR), Thermal gravimetric analysis (TGA) and Scanning electron microscopy (SEM) equipped with energy dispersive X-rays (EDX) to examine crystalline size and structure, purity, morphology, surface area and thermal stability. The prepared TiO2/AC nanosorbent exhibits enhanced surface area and high porosity. The adsorption capacity of the TiO2/AC nanosorbent was evaluated at both laboratory and industrial scales. The effect of contact time, adsorbent dose and heavy metals' initial concentration on the adsorption rate of Pb (II) and Cd (II) were also examined to optimise the adsorption performance of nanosorbent. Under the optimised condition, the percent removal efficiency for Pb (II) and Cd (II) was 91.48 and 93.13, respectively. Different isotherms and kinetic models have been applied to study the adsorption mechanism which suggested that adsorption is exothermic and physical in nature. The maximum adsorption capacity for Pb (II) and Cd (II) obtained by the Langmuir adsorption isotherm was found to be 101.01 and 24.45 mg/g, respectively. Among different kinetic models, Elovich and Weber-Morris intraparticle diffusion fitted well which suggested that the adsorption involves intraparticle diffusion. In addition, the fixed bed column prototype was designed to treat steel industry samples.

Different compositions of manganese (x = 1 & 3 wt. %) and nitrogen (y = 1 wt. %) co-doped TiO2 (MnxNyT) photocatalysts are prepared by the conventional sol-gel method. The crystallinity, optical properties, phase purity and surface morphology of prepared nano-photocatalysts were characterised in detail. The structural analyses show that the simultaneous doping with manganese and nitrogen controls the growth of TiO2 crystal structure having an average crystallite size in the range of 14.6 to 24.5 nm. The optical analysis also demonstrated that due to the synergistic effect of Mn and N, co-doped TiO2 represents the red-shift in the absorption band edge from 3.33 eV to 2.39 eV, which improved the response of TiO2 structure towards the visible region and enhanced electron-hole separation. Among all, Mn3N1T represented the better photocatalytic efficiency against anionic dyes (Blue KBR and Red GD) and phenol under optimised conditions (such as initial substrate's concentration = 20 ppm, photocatalyst dose = 0.5 g and solution pH of 3 and 7, respectively) due to its low bandgap, low crystallite size and high absorptivity towards the visible region. The kinetics study also showed that the degradation of dyes and phenol over Mn3N1T followed pseudo-first-order kinetics.

Non-uniform, non-spherical bismuth oxide deposited on titanium vanadium oxide (3

Membrane fouling remains a challenge to the membrane technology. Herein, we report the fabrication of composite membranes of polyaniline/polyvinylidene fluoride (PANI/PVDF) blended with nanodiamond (ND) with improved antifouling properties. The designed membranes were characterized by XRD, FTIR and SEM techniques. Characterization analysis revealed that addition of ND has maintained the structural integrity and porosity of composite membranes. The membrane permeation and antifouling performances were tested for hydrophilicity, porosity, pure water flux, shrinkage ratio, salt rejection of zinc acetate and copper acetate, and their fouling recovery ratio (FRR) measurements. A high solvent content ratio of 0.55 and a low shrinkage ratio of <12% due to enhanced hydrophilicity and porosity of the composite membrane with fouling-recovery of membranes to 88% were achieved. Separation of copper and zinc ions from aqueous solution was achieved. These findings imply that ND-based PANI/PVDF composite membranes can effectively serve as microfiltration membranes in industrial and municipal wastewater treatment.

Adsorption of methylene blue from aqueous solution by activated carbon-loaded copper oxide nanocomposites (CuO@AC) was investigated. The activated carbon was derived from Prosopis juliflora (Mesquite) pods which is a noxious wild invader. Both activated carbon and CuO@AC were prepared at low-temperature in shortest possible duration ensuring environmentally-friendly and green synthesis approach. CuO@AC nanocomposites were characterized by XRD, SEM, EDX, and FTIR and tested for adsorption kinetics, isotherm, thermodynamics, mechanism and effect of experimental variables on removal of MB from aqueous solution. The obtained results revealed that > 97% MB removal over CuO@AC was achieved within 15 min by using 0.1 g adsorbent dosage, 10 mg/L MB at neutral pH and 313 K. The monolayer adsorption of MB was found to be favourable with maximum adsorption capacity to be 54.73 mg/g at 313 K. Both the gradual decrease in values of & UDelta;G,-5.865 kJ/mol at 293 K to-7.71 kJ/mol at 313 K) and positive values of delta S (95.12 J/K/mol) and delta H (22.035 kJ/mol) are indicative of spontaneity and endothermicity of MB adsorption in the current study under studied experimental conditions. CuO@AC nanocomposite has demonstrated stability and recyclability to four adsorption cycles with nearly same adsorption efficiency. These findings prove that CuO@AC nanocomposite can be utilized as an excellent adsorbent for wastewater treatment at wider scale.

The groundwater is one of the biggest natural resources for providing drinking water to millions of people all around the globe. However, the presence of large amount of arsenic(V) in water causes serious health hazards to the consumers which necessitates the development of cost-effective remediation. The CuO/TiO2 nanocomposites were prepared by the precipitation-deposition method for the removal of the arsenate ion (AsO43-) from water. The prepared samples were characterized by powder X-ray diffraction, Fourier transform infrared, and scanning electron microscopy to examine crystallite size and structure, material purity, textural features, morphology, and surface area. The effect of different operating parameters such as pH, contact time, initial concentration of arsenic(V) and nanocomposite dose on the removal rate of arsenic(V) was examined to optimize the adsorption performance of the CuO/TiO2 nanocomposite. In addition, the adsorption mechanism was studied by employing Langmuir and Freundlich adsorption isotherms to gain better understanding of the adsorption mechanism. The Freundlich adsorption isotherm fits well with the experimental data and the maximum adsorption capacity of the Langmuir model was found to be 90 mg/g for arsenic(V). The CuO/TiO2 nanocomposite shows remarkable adsorption performance for the treatment of arsenic(V) contaminated water samples. This study provides a cost-effective solution for the safe use of groundwater contaminated with arsenic.

We discuss anisotropic source describing the phenomena of collapse and expansion in the context of f(R, T) theory. For this purpose, we take an auxiliary solution of the Einstein field equations and evaluate expansion scalar whose negative values lead to collapse and positive values give expansion. For both cases, the behavior of density, pressures as well as anisotropic parameter is explored and the effects of model parameter on these quantities are examined. We also check the energy conditions for physical viability of these generating solutions.

In current study nanodiamonds (NDs) and LiCl were added into poly (vinylidene fluoride) (PVDF) matrix to prepare PVDF/ND/LiCl nancomposite membranes by using phase inversion method. Fabrication of nanocomposite membranes was then confirmed by XRD, SEM, FTIR and TGA. The results showed that the nanodiamonds were incorporated into the pores and onto the surface of PVDF membranes. The effect of NDs loading (0.1 to 0.7 wt%) on nanocomposite membranes properties was studied. The presence of NDs in PVDF substrate provided it a hydrophilic character thus improved permeability, antifouling performance and decreased shrinkage ratio. PNL-0.5 (adding 0.5% NDs with PVDF membrane) exhibited the best results with fouling recovery ratio of 95%, malachite green dye rejection of 95%, decolorization rate of 89% and and mechanical stability up to 15 cycles. These results showed that the characteristics of PNL-0.5 were best and can be used for the removal of dyes from industrial effluent.

Realizing the importance of keeping our planet clean, researchers are actively working for eco-friendly alternative technologies for all areas of daily life. The presence of colored dye pollutants in water due to industrial, agricultural and domestic activities has led to the global need for the development of new and improved but efficient technologies to effectively address the challenges of water quality. Therefore it is necessary to develop technologies that could completely remove contaminants from contaminated waters. Semiconductor-mediated photocatalysis is a well-established technique for degradation of organic pollutants. TiO2 (titania) nanocatalysts have a proven potential to treat “difficult-to-remove” contaminants and thus are expected to play an important role in the remediation of environmental and pollution challenges. Doped-titania structures (nanoparticles, nanotubes, nanowires) are intended to be both supplementary and complementary to the present water-treatment technologies through the degradation of hazardous chemical wastes to innocuous end-products, that is, CO2 and H2O. This review article brings to attention the present scenario of water pollution, textile waste water, waste water treatment strategies, in particular, advancements of titania photocatalytic nanostructures in their use for water-treatment processes.

Water is precious natural resource on earth but rapid industrialization and effluent discharge from domestic, agriculture and municipal wastes is polluting water continuously.Membrane technology provide solution to water related problems and used as an attractive tool for removal of pollutants from water.Different types of polymeric membranes are used for wastewater treatment but certain drawbacks are related to polymeric membranes such as hydrophobicity, fouling and low mechanical strength.Incorporation of nanoparticle in polymeric membranes enhances the membrane properties.Recently nanocomposite membranes are developed that increased hydrophilicity, improved mechanical properties and enhanced rejection efficiencies of polymeric membranes.Among different types of polymeric membranes, polyvinylidene fluoride nanocomposites membranes are widely used for removing various contaminants from wastewater.It is reported that polyvinylidene fluoride based nanocomposite membranes possess good separation efficiency for the removal of different pollutants.In this review several polyvinylidene fluoride membranes incorporated with metal oxide such as titanium dioxide, aluminium oxide, silicon oxide, zinc oxide, carbon nanotubes and graphene oxide based nanocomposite membranes have been discussed for wastewater treatment.The current study objective is to summarize the applications of polyvinylidene fluoride based nanocomposite membranes for the removal of different pollutants from wastewater.

Arsenic is highly carcinogenic element and less concentration of this chemical element makes natural water unsafe for human consumption. Versatile techniques including adsorption method have been established to remove the arsenic from water. However, adsorption is found to be one of effective method for the remediation of arsenic from contaminated water. Different types of natural adsorbents i.e. clays, waste materials, carbon based material have been studied widely for the adsorption of arsenic. Recently, nanotechnology is considered to be one of the best technology for waste water treatment. Therefore researchers have synthesized several types of nanoadsorbents and investigated them for the removal of various pollutants including arsenic from water. Now days, attention is paid on development of nanocomposite materials which are proven as competent arsenic adsorbent candidate as compared to other adsorbents due to dominant structural and surface features. Various metal/metal oxide based nanocomposites have been developed and studied for arsenic removal from aqueous media. It has been reported that TiO2 based nanocomposite exhibit stong affinity for both inorganic form of arsenic. Therefore, in this review numerous metal or metal oxide based titania nanocomposites i.e. TiO2-αFe2O3, NHITO, Ce-Ti oxide, Zr-TiO2, RGO-MFT etc. have been discussed in details for the water treatment containing arsenic. This review also presents an overview of low cost adsorbents, titania based nanoadsorbent and hybrid titania nanostructures for the removal of arsenic. In this review paper the particle size, surface area and adsorption efficiency of these titania based materials at different pH are also been presented in tabulated form. It provides the opportunity to choose best titania based nanocomposites for the treatment of arsenic polluted water.

Membrane technologies have been at the heart of research since last few decades with latest improvement in both fabrication and analytical tools. Porous polymeric membranes have gained much attention in this perspective for their utilization in a variety of fields. This review article is mainly concerned with reporting the research work being conducted so far in the direction of fabricating porous polymer membranes. In this context, various additives used to design porous polymer membranes resulting in well-controlled and broad variety of morphologies are being discussed. However, the emphasis of this review is on the use of various additives mainly different water-soluble pore formers (WSP) in polymeric membranes such as PVP, PEG and PAA. The effect of these WSP on pure water flux, hydrophilicity, fouling, mechanical strength and applications of porous membranes in various fields has also been explained in detail.

Polyvinylidene fluoride and an ionic liquid, 1-butyl-3-methylimidazolium bromide-based ionogel membranes, were fabricated by phase inversion method. The concentration of ionic liquid was varied in these membranes ranging from 0 to 15 wt%. The membranes were characterized by X-ray diffraction analysis, thermogravimetric analysis, Fourier transform infrared spectroscopy and scanning electron microscopy. The X-ray diffraction and Fourier transform infrared spectroscopy results confirmed the conversion of alpha phase of pure polyvinylidene fluoride into beta phase with the addition of ionic liquid. The thermogravimetric results exhibited an increase in thermal stability, whereas scanning electron microscopy analysis displayed an increase in porosity of the ionogel membranes with the increase in concentration of ionic liquid. These fabricated membranes were applied for desalination such as the removal of copper nitrate trihydrate and cobalt nitrate hexahydrate from water. Different membrane properties including porosity, water content, solvent content, shrinkage ratio, pure water flux, salt rejection and fouling recovery ratio were also studied for the determination of applicability of these membranes in desalination. The porosity, water content, pure water flux and fouling recovery ratio manifested an increasing trend. The solvent content decreased as we moved from less hydrophobic solvents toward more hydrophobic solvents. Shrinkage ratio also decreased with the subsequent addition of ionic liquid. All these results evidenced the efficiency of these membranes in desalination and are mainly attributed to an increase in hydrophilicity and porosity of membranes.

Ionogels have emerged as one of the most interesting and captivating form of composites which credits to the outstanding characteristics. One of the most important constituent of ionogels is ionic liquid, which show many attractive properties notably non-volatility, in-flammability, negligible vapor pressure, tunability, thermal stability and solvating ability. A large variety of matrix materials have been under consideration for ionogels, presently, polymer/ionic liquid based ionogels have attracted much attention. Numerous polymeric materials such as have been utilized for these polymer/ionic liquids based ionogels. Polyvinylidene fluoride (PVDF) has been on top of the line as a matrix material for polymer based ionogels owing to its stability, aging and chemical resistance and mechanical strength. This review is primarily concerned with the properties of polyvinylidene fluoride based ionogels with an emphasis on their applications in various domains electrochemical devices, gas separation and liquid/liquid separations.