Search

[Display omitted] • Overview of fundamentals of Nb 2 O 5 as photocatalyst-structure and properties. • Heterojunction photocatalysts -Z and S scheme- charge transfer routes. • Recent advances in Nb 2 O 5 based heterojunctions for photocatalytic applications. • Strategies for improving the photocatalytic performance Nb 2 O 5 based heterojunctions. Significant advancements in the field of photocatalysis in recent years have highlighted the heterojunctions based on Nb 2 O 5 as a focal point of research. This comprehensive review diligently analyses the progress in Nb 2 O 5 -based heterojunctions for their application in photocatalysis, focusing on synthesis, characteristics and their pivotal role in addressing crucial energy and environmental challenges. The review emphasizes the fundamental principles of photocatalysis in pollutant removal and H 2 generation, elucidating key processes such as light absorption, charge generation and surface reactions. The different types of heterojunctions, their basic principles and role in enhancing the charge separation and overall photocatlytic performance have been discussed. The recent advances in Nb 2 O 5 -based heterojunctions are extensively discussed for the photocatalytic applications such as pollutants removal and H 2 evolution. Furthermore, the review delves into strategies employed to enhance the photocatalytic activity of Nb 2 O 5 -based heterojunctions such as doping, oxygen vacancies modification, morphological engineering and atomic control, as well as loading with support materials. Each strategy is explained, emphasizing its impact on charge separation and overall efficiency. The review concludes by highlighting existing challenges and providing insights into potential future directions that integrates synthetic processes, novel methods for photoelectric characterization, and an in-depth understanding of the local structure of Nb 2 O 5. This review serves as a valuable resource for researchers in the field, offering a comprehensive overview of the state-of-the-art in Nb 2 O 5 -based heterojunctions for advanced photocatalytic applications. [ABSTRACT FROM AUTHOR]

Cation-intercalated graphene oxide (GO) membrane has emerged as a promising candidate for desalination applications as reverse osmosis (RO) membrane. This study constructs GO membranes with different cations (K+ or Mg2+) and investigates the potential of these membranes in boron removal via nonequilibrium molecular dynamics simulations. In the aquatic environment, boron can exist in the form of boric acid or borate ion, depending on the pH of the solution. As a result, this study considers two forms of boron. This study reveals that the GO membranes effectively reject negatively charged borate ions due to their bigger hydration shell and stronger electrostatic repulsion with the membrane than neutral boric acid molecules. Moreover, K+ ion intercalated GO membranes showed higher boron rejection than Mg2+ ion intercalated GO membranes owing to weaker electrostatic attraction of K+ ions with the boric acid (or borate ions). Additionally, a summary of the effects of oxygen-containing functional groups of the GO membrane on boron rejection is provided. Since the hydroxyl and epoxy functional groups interact with boric acid molecules more strongly, these molecules are prevented from permeating through the membrane. On the other hand, the permeation rate of borate ions declines because of their stronger interactions with the carboxyl functional groups. Furthermore, Mg2+ ion intercalated GO membranes exhibited higher water permeance, excellent Na+ rejection, and poor Cl− rejection compared to K+ ion intercalated GO membranes. • The effects of intercalated cations inside the GO layers on boron rejection are investigated. • GO membranes reject borate ions effectively when compared to boric acid. • The impact of oxygen-containing functional groups of GO membranes on boron rejection is presented. [ABSTRACT FROM AUTHOR]

• g-C 3 N 4 and MOFs based heterojunctions –synthesis routes and advantages. • Types of g-C 3 N 4 and MOFs heterojunctions were discussed-modification strategies. • g-C 3 N 4 and MOFs based heterojunctions for photocatalytic environmental remediation and energy production. • Conclusion and future research prospects on g-C 3 N 4 and MOFs based on heterojunctions. Photocatalytic technology has emerged as a promising solution for environmental remediation and energy production, and the development of efficient and stable photocatalysts is of great importance. Recent advances in g-C 3 N 4 /Metal Organic Frameworks (MOFs) heterojunctions have shown excellent potential in achieving high-performance photocatalytic environmental remediation and energy production. In this review, we have summarized the recent advances in the design and synthesis of g-C 3 N 4 /MOFs heterojunctions and their application in photocatalytic environmental remediation and energy production. We have discussed the advantages and challenges of g-C 3 N 4 /MOFs heterojunctions, such as enhanced light absorption, increased surface area, and improved electron-hole separation, and their effects on photocatalytic performance. We also highlight the recent research progress in the utilization of g-C 3 N 4 /MOFs heterojunctions for various environmental remediation applications, including the degradation of organic pollutants and the removal of heavy metals, as well as for energy production applications such as hydrogen evolution and CO 2 reduction. Furthermore, we provide an overview of the latest theoretical and experimental investigations into the mechanisms of photocatalysis in g-C 3 N 4 /MOFs heterojunctions, which can help to guide the rational design of high-performance photocatalysts. Our analysis of the literature reveals that g-C 3 N 4 /MOF heterojunctions have demonstrated excellent photocatalytic activity for the degradation of various pollutants, such as methyl orange, rhodamine B, and bisphenol A. For instance, a g-C 3 N 4 /ZIF-8 heterojunction achieved a photocatalytic degradation rate of 99.9% for methyl orange under visible light irradiation within 60 min. Moreover, the g-C 3 N 4 /MOF heterojunctions have also been found to be efficient in water splitting for hydrogen production. For instance, a g-C 3 N 4 /UiO-66 heterojunction achieved a hydrogen production rate of 1260 μmol h−1g−1 under visible light irradiation. The recent data on the advances in g-C 3 N 4 /MOFs heterojunctions demonstrate their enormous potential for practical applications in photocatalytic environmental remediation and energy production. [ABSTRACT FROM AUTHOR]

Abstract This article examines hydromagnetic flow of Carreau nanomaterial over a stretched surface. Buongiorno nanofluid model is used in mathematical modelling. Here thermophoresis and Brownian diffusion are slip mechanisms under consideration. Energy equation is modelled via heat source/sink, Joule heating, nonlinear radiation and dissipation effects. The compact form of flow equations are changed to components forms through implementation of boundary layer concept. Suitable transformations give rise to ODEs. The obtained system is solved through homotopy method. The velocity, mass concentration, entropy generation, temperature, skin friction, Bejan number and Nusselt number are examined through graphical sketch. The obtained outcomes present that entropy generation boosts for higher magnetic parameter, Brinkman number and concentration ratio parameter while it diminishes via Brownian diffusion parameter. [ABSTRACT FROM AUTHOR]

Abstract The dyes are one of major pollutants discharged to water bodies without any premeditation. Their undesirable detection in aqueous bodies has created a menace as they tend to disturb the complete aquatic ecosystem by directly hindering the photosynthetic process of aquatic flora. Thus pre and post discharge remediation of these dyes are of immense significance. In the present study, novel OG/La 2 O 3 /ZrO 2 nanocomposite having high photocatalytic ability was prepared by co-precipitation method. Visible photocatalytic ability of the nanocomposite was employed for the degradation of fast green dye as a target pollutant. The OG/La 2 O 3 /ZrO 2 nanocomposite was well characterized using various techniques as FTIR, XRD, SEM, TEM and XPS etc. The nanocomposite also exhibited adsorption capability due to the presence of oxidized graphite (OG) sheets those provided high surface area for the fast green molecules to get adsorb onto them. High degradation efficiency (89%) was obtained within 90 min of visible light irradiation. Effect of pH, photocatalyst amount and light intensity was also studied. Superoxide and hydroxyl radicals were found to be the major reacting species as confirmed by the scavenging studies. Furthermore, OG/La 2 O 3 /ZrO 2 nanocomposite exhibited high reusability interpreting the nanocomposite as a proficient photocatalyst with active utilization for treating industrial waste water. Graphical abstract Unlabelled Image Highlights • OG/La 2 O 3 /ZrO 2 nanocomposite was fabricated by simple co-precipitation method. • OG sheets provided high surface area for attachment of La 2 O 3 and ZrO 2 particles. • Superoxide and hydroxyl radicals were the major reacting species. • Catalytic reduction of fast green dye by OG/La 2 O 3 /ZrO 2 nanocomposite [ABSTRACT FROM AUTHOR]

Abstract Novel Zr 2 Ni 1 Cu 7 trimetallic nano-alloy (TNA) and Zr 2 Ni 1 Cu 7 /Si 3 N 4 trimetallic nano-alloy composite (TNAC) have been successfully prepared by facile microwave reduction method. The synthesis of TNA and TNAC was ascertained by characterizing them by using various techniques such as SEM, TEM, XRD, EDX and FTIR etc. The EDX shows the presence of all constituents in TNA and TNAC. The XRD study demonstrated the crystalline and semi-crystalline nature of TNA and TNAC. The optical band gap study revealed that TNAC (2.47 eV) has lower band gap then TNA (2.54 eV). The visible light photocatalytic activity of Zr 2 Ni 1 Cu 7 TNA and Zr 2 Ni 1 Cu 7 /Si 3 N 4 TNAC has been successfully utilized for the photodegradation of methylene blue (MB). The presence of H 2 O 2 has been found to influence the photodegradation rate. Photodegradation results presented that maximum degradation was observed in the presence of H 2 O 2 and Zr 2 Ni 1 Cu 7 TNAC (92%). Scavenging activity has revealed that the hydroxyl radicals were the major reacting species. These species successfully degraded the MB into various intermediates that has successfully been determined by the LC-MS. Kinetic studies indicated that the degradation of MB by Zr 2 Ni 1 Cu 7 TNA and Zr 2 Ni 1 Cu 7 /Si 3 N 4 TNAC followed pseudo-first-order kinetics. Graphical abstract Unlabelled Image Highlights • Zr 2 Ni 1 Cu 7 TNA and Zr 2 Ni 1 Cu 7 /Si 3 N 4 TNAC synthesized by facile microwave reduction method. • Synthesis of TNA and TNAC were ascertained by characterizing them with SEM, TEM, XRD, EDX and FTIR. • The optical band gap study revealed that TNAC(2.47 eV) has lower band gap then TNA (2.54 eV) • TNA and TNAC were successfully employed for the photodegradation of methylene blue. [ABSTRACT FROM AUTHOR]

Surfactant increases recovery of oil from reservoir by decreasing the interfacial tension (IFT) between oleic and aqueous phase and changing wettability of reservoir rock from oil-wet to water-wet. In current work, a carboxybetaine based zwitterionic surfactant have been synthesized by quaternization of dodecyldimethylamine with chloroacetate. The synthesized surfactant has been characterized by FTIR, 1 H NMR and TGA analysis. The physicochemical properties of the synthesized surfactant were measured to check its effectiveness for application in chemical enhanced oil recovery (EOR). The synthesized surfactant decreased the IFT between crude oil and water from 17 mN/m to 3.77 × 10 − 2 mN/m at a low critical micelle concentration (CMC) of 500 ppm. The synthesized surfactant solution was also effective in changing the wettability of oil wet quartz sample to water wet. Sand pack experiments showed additional oil recovery of 27.03% by flooding of surfactant slug at CMC. These results evidence the suitability of the synthesized surfactant for application in chemical EOR. [ABSTRACT FROM AUTHOR]

• Synthesis of conducting polymer-alginate composite hydrogels. • Influence of conducting polymer on rheology. • Release kinetics of metformin hydrochloride. • Zero order release behavior of conducting polymer-alginate composite hydrogels. The present study reports synthesis and characterization of sodium alginate (Na-ALG) based composite hydrogels using polyaniline (PANI), poly(o-phenylenediamine) (POPD), poly(1-naphthylamine) (PNA), and poly (vinylidene fluoride) (PVDF). The synthesised hydrogels were investigated for their spectral, morphological and rheological properties. Metformin hydrochloride (MFH) was chosen as a model drug to study the release profiles using intestinal fluid pH of 7.4. Approximately 99 % drug release was attained for POPD/Na-ALG at 37 °C over a period of 12 h. Release kinetics was confirmed by employing the zero-order, first-order, Higuchi and Korsmeyer-Peppas models. It was found that almost all composite hydrogels followed the zero order and Korsmeyer-Peppas models. The incorporation of conducting polymers as crosslinking agents was found to have a significant impact on the release behaviour and this property could be utilised to optimise and control the release of metformin hydrochloride as per desirable dosages. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ni 5 P 4 /g-C 3 N 4 S-scheme dual-function heterojunction photocatalyst was prepared. • 25NP/CN junction shows 40.1 mmol g-1h-1H 2 evolution and 94.4 % CBZ removal in a coupled process. • Holes and OH radicals for CBZ degradation and electrons for H 2 generation via e-/H 2 O and 2e-/2H+. • Intermolecular H+ transfer via cyclic intermediate between Ni and degradation products. • Junction works in oxic/anoxic mediums- detailed mechanisms analysed. With a goal of waste-to-energy conversion, herein we report synchronous hydrogen evolution and pollutant degradation via photocatalysis utilizing novel Ni 5 P 4 /g-C 3 N 4 S-scheme (Step scheme) heterojunction. The 25 %Ni 5 P 4 /g-C 3 N 4 (25NP/CN) sample generates 40.1 mmol g-1h-1hydrogen evolution and 94.4 % carbamazepine degradation simultaneously under visible light and anaerobic conditions. Furthermore, the hydrogen evolution with carbamazepine, bisphenol A, sulfamethoxazole and rhodamine B is manifolds higher than in water. From The in-situ XPS results confirm the S-scheme transfer between Ni 5 P 4 and g-C 3 N 4. The presence of Ni0@Ni 5 P 4 where strong covalent interactions between Ni0 and Ni-P single layers on Ni 5 -P 4 not only enhanced the visible absorption, charge transfer but also leads to hydrogen formation by H+ transfer via a cyclic intermediate in a co-ordinate complex of degradation intermediates with Ni. This route is in addition to obvious e-/H+. The CBZ degradation and hydrogen evolution in aerobic/oxic conditions was also studied and 25NP/CN performs well under this atmosphere, inferring that oxidised intermediates act as electron donors and maintains the H 2 evolution in longer run too. The photogenerated holes directly oxidized the pollutant in addition to OH radicals in anoxic medium and separated/accumulated electrons leads to hydrogen evolution. The scavenging experiments reveal that photogenerated holes directly oxidized the pollutant in addition to OH radicals in anoxic medium and separated/accumulated high potential electrons (via S-scheme transfer) leads to hydrogen evolution. The clean energy production and pollutant mineralization are synchronously achieved. Henceforth, a waste-to-energy route is proposed by coupling photocatalytic hydrogen evolution to environmental restoration. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel Z-scheme Bi 7 O 9 I 3 /B 4 C heterojunction synthesized by hydrothermal route. • Antibiotic as sacrificial agent- H 2 evolution and antibiotic removal simultaneously. • Antibiotic degradation route and photocatalytic mechanism probed. • Waste to clean energy concept. The dual-function photocatalytic systems with a promising capability for hydrogen evolution and simultaneous pollutant degradation are surely a significant step towards waste-to-energy conversion goals. However, the performance of such photocatalysts is often limited by poor visible-light activity, charge separation and surface reverse reaction involving photogenerated electrons and radicals/intermediates. In this work, we report hydrothermal synthesis of novel Bi 7 O 9 I 3 /B 4 C (BIBC) heterojunction photocatalyst for advanced Norfloxacin antibiotic degradation with simultaneous hydrogen evolution under visible light. In particular, BIBC-30 heterojunction shows H 2 evolution rate of 812 μmol g−1h−1 with simultaneous 94.2% NFN removal which are much higher than bare B 4 C (∼6 times) and Bi 7 O 9 I 3 (∼4 times). Under oxic/aerobic conditions too, a high 456.3 μmol g−1h−1H 2 evolution with nearly complete norfloxacin degradation was achieved. The low band gap of Bi 7 O 9 I 3 and presence of metallic Bio extends the absorbance to NIR region and B 4 C enlarges the surface area of junction along with suppression of the back reaction. It was observed that BIBC heterojunction exhibits manifolds H 2 evolution rate with NFN as sacrificial agent (18.3% apparent quantum efficiency) is manifolds higher than pure water, methanol, triethanolamine and rhodamine B. An effective Z-scheme charge transfer facilitated by Bio is active in the intimately coupled heterojunction with suitably placed energy bands. This work shows that waste to energy conversion can be promisingly achieved by performing H 2 evolution and pollutant removal simultaneously. [ABSTRACT FROM AUTHOR]

Abstract: Molar volume, viscosity and conductance of lithium chloride (LiCl), sodium chloride (NaCl) and potassium chloride (KCl) in 0.01m aqueous ascorbic acid have been calculated from density, viscosity and conductance data at temperatures 303.15, 308.15, 313.15 and 318.15K. The solute–solvent interactions for LiCl, NaCl and KCl have been inferred from ϕ v o, B-coefficient of Jones–Dole equation and Λ m o values. The structure making/breaking behavior of LiCl, NaCl and KCl is inferred from the sign of [∂2 ϕ v o/∂T2]p, dB/dT and temperature coefficient of Walden product i.e. d(Λ m o η o)/dT values. It has been found from molar volume, viscosity and conductance studies that LiCl, NaCl and KCl behaves as structure-breaker in 0.01m aqueous ascorbic acid solution. The energy of activation for LiCl, NaCl and KCl is calculated from conductance and viscosity data and it has found that E Λ is less than E η . [Copyright &y& Elsevier]

The properties of lipid bilayers in contact with trehalose solutions in water were studied in the full concentration range using molecular dynamics simulations. The mechanism of trehalose interaction with the bilayer surface was analysed considering hydrogen bonding and molecular arrangements as well as the possible changes in bilayer properties. The effect of concentration of the possible mechanisms of trehalose action as membrane protectant were discussed to infer the possible evolution of water replacement by trehalose at the membrane surface and its relationship with the trehalose role in anhydrobiosis and drying processes. Unlabelled Image • Anhidrobiosis in presence of trehalose • Trehalose solution in presence interacting with lipid membranes • Water replacement mechanisms • Intermolecular forces at lipid bilayer interfaces • Nanoscopic characterization of bilayer structuring upon water replacement [ABSTRACT FROM AUTHOR]

Rationally fabricated Z -scheme hetero-junctions with intimate interfacial contact have proven to accelerate the photocatalytic degradation of noxious pollutants by effectively suppressing the recombination and promoting charges transfer rate. Herein, we report fabrication of reduced graphene oxide (RGO) modified LaTiO 2 N/Bi 2 S 3 heterojunction photocatalyst by sovothermal route. The microstructure analysis, structure determination, electronic and optical analysis of as prepared photocatalysts was done by using multiple techniques. The Z -scheme LaTiO 2 N/Bi 2 S 3 @RGO (LBR) photocatalyst shows remarkable performance for photo-degradation of tetracycline (TC) under visible light. 96.4% TC was eliminated within 90 min under visible light with ~100% removal in 60 min under full spectrum irradiation. In addition the heterojunction shows 80.2% TC removal under natural sunlight irradiation. The TC degradation with LBR heterojunction is ~9 times faster than bare Bi 2 S 3. The Z -scheme transfer follows the route as Bi 2 S 3 → RGO → LaTiO 2 N and provides a swift path for movement of electrons from CB of LaTiO 2 N to VB of Bi 2 S 3. The possible degradation route of TC has also been proposed based on quenching experiments and identification of degradation intermediates by Liquid chromatography-mass spectrometry (LC-MS). The quenching experiments reveal that O 2 – radicals are the main active species involved followed by OH radicals which has been explained by thermodynamic feasibility of their production from the junction arrangement. The mechanism has been explained by Z -scheme transfer by comparing to the conventional type-II junction. The enhancement in photocatalytic activity is primarily attributed to Z-scheme charge transfer between LaTiO 2 N and Bi 2 S 3 facilitated by reduced graphene oxide sheet via strong interfacial contact maintaining high potential for redox conversions. The recycling experiments reveal the stability and reusability of the LBR hybrid photocatalyst with ability to perform under sunlight. The novel nitrides-phosphide based junction with improved properties for visible and solar photocatalytic activity provides future prospects in forming superior hetero-structures for environmental remediation. Unlabelled Image • LaTiO 2 N/Bi 2 S 3 @RGO heterojunction photocatalyst fabrication by simple solvothermal route. • High performance degradation of tetracycline-visible, full spectrum and sunlight • Interfacial charge transfer capacity-internal electric field–higher spectral capture. • Z-scheme and RGO lead to high charge separation, high redox capability, stability. • Thermodynamic feasibility and experimental findings suggest Z-scheme over conventional type-II transfer. [ABSTRACT FROM AUTHOR]

Graphitic carbon nitride based photocatalytic materials have proved to be one of most promising candidates for hazardous pollutant removal and clean energy production. Structural modification and engineering of various materials based on g-C 3 N 4 have been attempted to achieve solar energy harvesting, slow charge transfer and efficiency. Here we report synthesis of all metal free self-assembled carbon quantum dots and reduced graphene oxide layers modified S@g-C 3 N 4 /B@g-C 3 N 4 (CRSB) photocatalyst for visible and solar degradation of chloramphenicol (CMP) (10 mg L−1). Differently doped g-C 3 N 4 with different band structure forms a junction which grows into an effective Z -scheme photocatalyst. Extended visible absorption is achieved with optimized modification by reduced graphene oxide (RGO) and carbon quantum dots. The optical response, band structure and charge separation efficiency were tested by optical absorption, electrochemical impedance, Mott-Schottky plots and photo-luminescence. CQDs convert a typical type-II mechanism into effective Z -scheme transfer. For the best sample CRSB 99.1% CMP was photo-degraded in 90 min exposure to visible light and retention of high activity in natural solar light (92.4% in 120 min). A stable heterojunction has been attempted to design using boron doped g-C 3 N 4 and sulphur doped g-C 3 N 4 with different band positions via ratio optimization with enhanced charge transfer. The degradation rate for CRSB (0.0810 min−1) is 10 times than bare g-C 3 N 4 (0.00802 min−1). The optimized combination of carbon quantum dots and RGO with intimate interfacial contact for charge flow & reduced recombination, better adsorption of pollutant, high visible absorption and production of reactive oxygen species. The effect of pH, electrolytes and water matrix was studied for CMP degradation. The mechanism of degradation and mineralization was confirmed by liquid chromatography-mass spectrometry (LC-MS) analysis, scavenging experiments and electron spin resonance. It was observed that the chances of •O 2 – and •OH radicals increased on the formation of the junction as compared to individual doped and bare carbon nitride. The mineralization was ensured by high total organic removal and cyto-toxicity studies of treated water sample onto human peripheral blood (PBL) cells with high cell viability equivalent to untreated cells. This experiment supports the competence of optimally designed metal free and environmentally friendly cost-effective catalysts with higher photocatalytic efficiency for removal of hazardous pollutants. Unlabelled Image • S@g-C 3 N 4 and B@g-C 3 N 4 self-assembled junction • Heterojunction formed from differently doped g-C 3 N 4 • Modification by RGO and CQDs- All metal free catalyst • Intimate charge transfer at the interface-low recombination • Excellent visible and solar degradation of chloramphenicol • High mineralization-no toxicity on human blood cells [ABSTRACT FROM AUTHOR]

Fabrication of highly active photocatalysts that can be utilized for water detoxification is the need of time. In present work, we have synthesized La/Co/Ni TNPs and graphene oxide (GO) supported La/Co/Ni trimetallic nanocomposite (La/Co/Ni@GO TNC) using simple microwave method. The potential application of TNPs and TNC has been explored for photodegradation of 2-chlorophenol (2-CP) under natural sunlight irradiations. Among the two, La/Co/Ni@GO TNC (71% in 300 min) exhibited better photocatalytic ability as compared to La/Co/Ni TNPs (57% in 300 min). The superior performance of La/Co/Ni@GO TNC is credited to the efficient charge transfer and reduced electron-hole recombination ability. The band structure analysis, scavenging experiments and terephthalic acid studies have made it possible to finalise a probable degradation mechanism for 2-CP. Unlabelled Image • La/Co/Ni TNPs and La/Co/Ni @GO TNC synthesized by microwave reduction method • Photocatalytic degradation of 2-chlorophenol undertaken • GO offered high catalytic surface area and acted as sink • Band gap of 2.42 eV in the semiconductor region shown by La/Co/Ni @GO TNC • 71% degradation rate acquired in 300 min [ABSTRACT FROM AUTHOR]

The voluminous anthropogenic activities and non-regulated discharge of emerging pharmaceutical pollutants have led to deterioration of water quality characteristics and shortage of potable water. One of most ubiquitous problems is that the pharmaceutical pollutants are slowly developing resistance in pathogens, which increases the risks manifold. Conventional water treatment methods and technologies have been known to be inadequate for elimination of recalcitrant and emerging pollutants. Advanced oxidation processes have been exploited to the most for mineralizing the pollutants with some limitations especially toxic metal based catalysts and secondary pollution. However Fenton-based systems are considered to be safer as they utilize non-toxic chemicals. Homogeneous Fenton processes suffer from limitations as limited pH operational range, generation of Fe containing sludge etc. have shifted focus to heterogeneous systems. This review focusses on removal of pharmaceutical pollutants by homogeneous and heterogeneous Fenton, electro-Fenton, sono-Fenton, photo-Fenton and photo-electro-Fenton processes using nano-catalysts. Various types of new pharmaceutical pollutants, their emergence, characteristics and toxicity have been discussed to have an insight into quantity and variety. New Fenton-like catalysts have been designed and used for degradation of pollutants and high mineralization is also achieved in a wide pH-range. In addition Fenton catalysts capable of showing high mineralization using solar light have been prepared by various methods with and without iron based materials. In addition in this review we have also focused on complexities related to removal of pharmaceutical effluents and how they are addressed by Fenton systems. The review aims to assist researchers and engineers to gain fundamental understandings and critical view of Fenton process and its optimization processes, and hopefully with the knowledge it could bring new opportunities for the optimization and future development of Fenton process. The key advances in Fenton catalysts are innovations in design of ligands, junction designing for effective radical generation, reaction engineering, hydro-dynamical effects and complete mineralization. The combinations and coupling of biological oxidation, semiconductor photocatalysis with Fenton process for high performance pharmaceutical pollutants removal in pilot-scale experiments have been discussed and evaluated. • Pharmaceutical pollutants as emerging class of toxic pollutants. • Fenton, electro-Fenton, photo-Fenton processes: Safe, Cheap and environmental benign. • Controllable parameters for effective degradation of pharmaceutical pollutants. • Heterogeneous photo-Fenton reaction better than homogenous. • Focus on coupled Fenton and biological oxidation systems. [ABSTRACT FROM AUTHOR]

[Display omitted] • Core scale CFD simulation study of bio-based surfactant flooding. • Same meshed geometry for both water and surfactant flooding. • Mass transfer of surfactant using species transport model. • Species transport model coupled with multiphase VOF model. Bio-based surfactant flooding is encouraged as an EOR method, as it is obtained from natural sources and is economically attractive. In the present study, the EOR efficiency of a natural surfactant synthesized from rapseed oil has been simulated using ANSYS FLUENT. The process of oil recovery from a core by injection of surfactant has been simulated by incorporating core, brine, surfactant, and crude oil properties into the numerical model. Mass transfer of surfactant between the aqueous phase and crude oil has been modeled using species transport without a chemical reaction model. Species transport model has been coupled with the multiphase VOF model, where the flow of each phase is determined as per their respective viscous resistance. Experimental data of inlet pressure and oil production has been used for history matching and later used to visualize the oil flow through the porous media, concluding that simulation of surfactant flooding can be achieved by species transport model. [ABSTRACT FROM AUTHOR]

• Organic-inorganic hybrids of polythiophene (PTh) decorated ZnFe 2 O 4 nanoparticles. • Microwave-assisted catalytic degradation of Isoniazid drug. • 94% degradation in 24 min. • Analysis of degraded fragments. • Fukui index and proposed degradation pathay. This present work reports for the first time, microwave-assisted catalytic degradation of isoniazid drug using organic–inorganic hybrids of polythiophene (PTh) decorated ZnFe 2 O 4 nanoparticles. The hybrids were characterized using fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and scanning electron microscopy along with energy dispersive spectra (SEM-EDS). The nanohybrids were used as catalysts for the degradation of isoniazid (ISN) drug under microwave irradiation. Almost 94% degradation of isoniazid was attained within 24 min using 100 mg of the catalyst. The degraded drug fragments were analyzed using LCMS and a tentative mechanism of degradation was proposed. [ABSTRACT FROM AUTHOR]

The development of multifunctional materials, specially nanocomposites, exhibit new and interesting properties which can extend the applicability ranges to diverse fields. In this way, the use of tri metallic nanoparticles, and derives, demonstrated higher efficacy for purification, catalytic activities and as antibacterial agents. This work is concentrated on the fabrication of Fe/La/Zn trimetallic nanoparticles (TNPs) and Fe/La/Zn@GO trimetallic nanocomposite (TNC) using the micro-emulsion method, specially indicated as photocatalysts for remediation of the organic pollutant. An intense characterization was performed by employing techniques as scanning electron microscopy (SEM), X-Ray diffraction (XRD), transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FTIR). The potential applications of the Fe/La/Zn TNPs and Fe/La/Zn@GO TNC were explored for the photodegradation of phenylhydrazine in the presences of sunlight. Furthermore, the photocatalytic studies were performed under different conditions: (a) adsorption (in dark) followed by photocatalysis, and (b) simultaneously adsorptional-photocatalysis straight way in sunlight. It was observed that a reduction of 52% and 57.91% was achieved under sunlight using Fe/La/Zn TNPs and Fe/La/Zn@GO TNC, respectively. The optical band gap of Fe/La/Zn TNPs, and Fe/La/Zn@GO TNCs was found 2.73 eV and 2.30 eV, which lies in semiconductor region. On the other hand, the antimicrobial nature of TNPs and TNC was checked for E. coli and S. aureus. The inhibition zone exhibited a maximum at 150 μg/mL for Fe/La/Zn TNPs (19 mm), and Fe/La/Zn@GO TNC (17 mm). This study revealed that resulting materials can be defined as a novel class of advanced multifunctional materials which can be employed effectively for environmental remediation and antimicrobial studies. Unlabelled Image • Synthesis of Fe/La/Zn trimetallic nanoparticles (TNPs) and Fe/La/Zn@GO trimetallic nanocomposite (TNC) by micro emulsion way • Photodegradation of phenylhydrazine using Fe/La/Zn trimetallic nanoparticles and Fe/La/Zn@GO trimetallic nanocomposite • Photodegradation of 52% and 57.91% was achieved using Fe/La/Zn TNPs and Fe/La/Zn@GO TNC, respectively. • The optical band gap of Fe/La/Zn TNPs and Fe/La/Zn@GO TNCs was found to be 2.73 eV and 2.30 eV. • Antimicrobial nature of TNPs and TNC was checked beside E. coli and S. aureus. [ABSTRACT FROM AUTHOR]

[Display omitted] • Spectral methods have been used to investigate the interaction of R1 with HHb and BSA. • Thermodynamic parameters suggested exothermic spontaneous binding processes involving hydrogen bonding and van der Waal interaction. • Molecular docking and molecular dynamics have been utilized to discuss the principle binding sites of proteins for R1. • R1 proposes preferentially binding to the hydrophobic cavity in site III of proteins. A Rhodamine-based fluorescent probe R1 has been successfully utilized to detect BSA and HHb proteins via non-covalent bonding. The protein binding nature with R1 has been unravelled by the characteristic changes in absorption, emission and circular dichroism spectra that indicated their noticeable interaction. The experimental results have also shown the moderate strength between proteins and R1 from the quenching of proteins through the static quenching mechanism. The hyperchromism in the absorption band of proteins with R1 has given vital information and binding affinity values have been calculated from Stern-Volmer plots. The calculated values of the thermodynamic parameters revealed a spontaneous binding processes occurring primarily via hydrogen bonding and van der Waal interactions. Furthermore, in-silico approaches have been utilized to make a comparison and conclusion with spectroscopic results. The outcome of these studies could be useful to examine the drug-protein binding for further exploitation. [ABSTRACT FROM AUTHOR]

In pharmacy, semisynthetic antibiotics with beta-lactam ring are the most prominently used drugs. The use of these drugs for humans and animals is continuously expanding. Their presence in the water system even at low concentrations can prove to be fatal to living beings. Also, they can even grow antibiotic-resistant bacteria and thus elimination of such drugs becomes very essential. Our study is focused on batch experiments for adsorptive removal of ampicillin (AMP) and its cumulative release in different solutions using xanthan gum-cl-poly(itaconic acid)/bentonite (XG- cl -poly(IA)/BN) nanocomposite hydrogel. It was synthesized by facile microwave method. The adsorption data of AMP was analyzed using various isotherm models such as Langmuir, Freundlich, Temkin and kinetic models such as Pseudo-first order, Pseudo-second order and Intraparticle diffusion. The maximum adsorption capacity as determined from Langmuir model was 245.09 mg/g at 318 K and solution pH 7. Also, XG- cl -poly(IA)/BN nanocomposite hydrogel was evaluated for AMP release in distilled water and at different pH solutions (2.2, 5.4, 7.4 and 9.4). The maximum AMP release was observed at pH 2.2 (37%). Unlabelled Image • A novel XG- cl -poly(IA)/BN nanocomposite hydrogel was synthesized. • The maximum adsorption capacity for ampicillin was found out to be 245 mg/g. • Adsorption data correlated by isotherm models: Langmuir, Freundlich and Tempkin. • XG- cl -poly(IA)/BN nanocomposite hydrogel was evaluated for ampicillin release. • Maximum ampicillin release was observed at pH 2.2 (37%). [ABSTRACT FROM AUTHOR]

Fabricating magnetically recoverable solar-active photocatalysts with high performance capabilities for removal of recalcitrant and emerging pollutants has gained worldwide attention. Especially pharmaceutical pollutants as sulfonamides drugs which are now frequently detected in water systems are hard to remove because of their resistance to microbial and biological oxidation. This laboratory scale experiment presents synthesis of Mg substituted Zn nano-ferrite (Zn 1-x Mg x Fe 2 O 4) (x = 0, 0.2, 0.4) by facile modified sol-gel technique for sulfadiazine (SDZ) degradation. Effect of Mg doping on the zinc ferrite were investigated in this work which was analyzed by Transmission electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy and X-ray diffraction. The UV-diffuse reflectance spectroscopy studies reveal higher visible absorption extending to longer wavelengths. The VB of the ferrite catalyst shifts to 2.30 eV in substituted ferrite M2Z8 (x = 0.2) capable of hydroxyl radicals generation from H 2 O, which is difficult in parent ferrite without any Mg substitution. The electrochemical impedance spectroscopy and photo-current response analysis also reveal low impedance, higher charge flow and separation in case of M2Z8 catalyst which is reflected in the 99.1% SDZ degradation in 90 min with 73.2% total organic carbon removal in 120 min. Scavenging experiments confirm that hydroxyl radicals are main active species involved in degradation with Mg2+ and Fe3+ catalyzing the generation of hydroxyl radicals by undergoing redox process. LC-MS and TOC analysis confirm the drug mineralization. The work aims at fabricating solar active tunable photocatalysts for photo-degradation and mineralization of pharmaceutical pollutants using cost-effective approach. Unlabelled Image • Magnetic solar active nano-Zn 1-x Mg x Fe 2 O 4 photocatalyst-facile synthesis • Mg enhances the degradation rate and radical generation. • Shifting of CB and VB-Changed dynamics of radical generation • High performance degradation of sulfadiazine drug-visible and solar light • Mechanism elucidation, high mineralization and magnetic recovery [ABSTRACT FROM AUTHOR]

Deep eutectic solvents, a new genre of green solvent, easy to synthesize, low volatility and non-toxic in nature, emerged as an efficient extractant for denitrogenation. We have performed a molecular dynamics simulation study to investigate the role of glyceline as an extractant for removal of nitrogen impurities namely indole, pyrrole, pyridine, and quinoline from a model liquid fuel. Δ G transfer was evaluated to capture the thermodynamic feasibility of the transfer of nitrogen impurities from the fuel to the glyceline phase. Negative value of Δ G transfer was obtained for the nitrogen impurities, and the partition coefficient in the following order: indole > pyrrole > quinoline > pyridine. The simulation revealed that the chloride-ion possesses strong interaction with indole and pyrrole while glycerol favors quinoline and pyridine. The fuel phase was observed to be free from impurities while glyceline phase contained impurities, which was confirmed by the negative and positive values of Δ G transfer and partition coefficient respectively. The self-diffusion coefficient for indole was observed to be the lowest while pyridine possesses the highest value, which was found to be in agreement with the observations from radial and spatial distribution functions. Further, this understanding at the atomic level for liquid-liquid extraction will help in developing potential solvents for denitrogenation of liquid fuel. • A negative value of Δ G transfer indicates the thermodynamically favorable separation. • Trend of the partition coefficient follows indole > pyrrole > quinoline > pyridine. • Lowest and highest D self values were observed for indole and pyridine respectively. • Phase separation between fuel oil and deep eutectic solvent was clearly observed. [ABSTRACT FROM AUTHOR]

In the present work, we synthesized La/Cu/Zr trimetallic nanoparticles (TNPs) by microwave method, which is applied as an effective nanophotocatalyst for the removal of a ampicillin antibiotic from aqueous media. The prepared nanomaterial was characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The experimental results showed that prepared nanoparticles have high photodegradation tendency for the removal of ampicillin antibiotic from the aqueous solution. The pseudo-first-order equation represents the better kinetics of the photocatalytic process. The feasibility of ampicillin antibiotic adsorption onto La/Cu/Zr TNPs was also studied and the results showed that the adsorption was supported with spontaneous photodegradation process. A photocatalytic degradation 86% of the antibiotic has been observed. [ABSTRACT FROM AUTHOR]

Iron molybdophosphate (FeMoPO) nanoparticles have been fabricated using simple co-precipitation method. The nanoparticles showed promising ion exchange nature with ion exchange capacity of 1 meq g − 1 .The synthesis on nanoparticles has been ascertained by characterizing the material using various techniques including Fourier transform infrared spectroscopy (FTIR) scanning electron microscopy (SEM) and transmission electron microscopy (TEM). To investigate the ion exchange behavior of FeMoPO nanoparticles its physicochemical properties has been studied in detail such as thermal stability, pH titrations, and elution behavior. FeMoPO nanoparticles have been explored as potential candidature for photocatalytic remediation of malachite green (MG) dye from aqueous system. It has been observed that FeMoPO nanoparticles efficiently photodegraded 77% of hazardous MG dye in 5 h of photo-exposure. [ABSTRACT FROM AUTHOR]

[Display omitted] • System thermodynamics of the antisolvent crystallization is discussed. • Supersaturation, MSZW, induction time, crystallization kinetics are critically analysed. • Hydrodynamic modeling and CFD-based approach for LASC are critically reviewed. • A complete outlook of LASC is presented. • Modeling based LASC scale-up guidelines and challenges are discussed. Fine particles are in great demand in the pharmaceutical industry due to their versatile applications. Liquid antisolvent crystallization (LASC) is one of the promising approaches to prepare fine particles without requiring high energy. The interdependence of system thermodynamics, mass transfer kinetics, and the multi-phase hydrodynamics in the liquid antisolvent crystallization process is not well understood. In this review, the different modeling aspects of LASC are described from a fundamental perspective. The system thermodynamics of LASC is discussed and several models used in literature to predict the solubility in pure solvents and binary solvent mixtures are summarized. A detailed description of supersaturation, metastable zone width and induction time in antisolvent crystallization are presented and critically analyzed. The nucleation and growth kinetics are discussed and interpreted in terms of process variables. The hydrodynamic aspect of LASC which involves the mixing at different length scales is discussed and analyzed in detail. The CFD simulation-based approach to describe the interaction among different phenomena is critically reviewed. The crystallization scale-up, which is a major challenge in the LASC process, is discussed. A guideline for crystallization scale-up using the CFD-based modeling approach is presented which will be helpful to prospective researchers. [ABSTRACT FROM AUTHOR]