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Abstract: Composite ultrafiltration membranes were prepared by applying thin coating of polyvinyl acetate (PVAc) over ceramic support by using a modified dip-coating method. Well-known dip coating method was not found suitable for PVAc, as the polymer solution (N,N-di-methyl acetamide solvent), was not viscous enough for uniform coating. In the modified technique, a secondary solvent (water) was used for the removal of DMAc rather than drying it from the solution. For studying the effect of polymer concentration and dipping time over membrane parameters, twelve different membranes were prepared using four different concentrations (10%, 20%, 30% and 40%) and three dipping time (30s, 60s and 120s). Membranes were characterized with TGA, SEM, air and hydraulic permeability and acid/base treatment. From gas permeability study, the pore sizes were found between 150 and 9nm. The lowest pore size membrane (9nm) was applied for the purification of lysozyme from chicken egg white (CEW) using three different concentrations. pH 11.0 was found as most suitable for the purification using the prepared membrane and over 98% of transmission of LS were found. [Copyright &y& Elsevier]

This work reports the prediction of selective extraction of cresol from aqueous solutions using ionic liquids (ILs) as the solvent. Judicious screening of various ILs was carried out for all the three forms of cresol (i.e., o-cresol, m-cresol, and p-cresol). A quantum chemical based theoretical model “conductor-like screening model for real solvents” (COSMO-RS) was used to predict the selectivity of cresol in aqueous medium at infinite dilution. A screening of 360 possible ILs from 15 cations and 24 anions was carried out to determine the best IL for the removal of cresol from water. Amongst the phosphonium and imidazolium based cations, trihexyl tetradecylphosphonium [THTDP] and 1-octyl-3-methylimidazolium [OMIM] gave the highest selectivity other than the anions bromide and chloride. The selectivities for different cresols followed the pattern: m-cresol > p-cresol > o-cresol. Similarly for pyridinium and quinolium based cations, 1-ethylpyridinium [EPY] and 1-octylquinolium [OQU] gave the highest selectivity. Amongst the two cations studied for pyrrolidinium based cations, 1-hexyl-1-methylpyrrolidinium [HMPL] was the best. Trihexyl tetradecylphosphonium salicyclate [THTDP][SAL] gave the highest selectivity of 662 amongst all the ILs screened. [ABSTRACT FROM AUTHOR]

Ceramic disc type microfiltration membranes (50 mm diameter and 5 mm thickness) were prepared by the paste method from different compositions of clay, kaolin, and binding agents like sodium carbonate, sodium metasilicate, boric acid, and sintered at different temperatures. All the membranes were characterized by TGA, SEM, XRD, water permeability test, and acid-base treatment. With the increase of sintering temperature, the pore size as well as the permeability and flexural strength were increasing while porosity and pore density were decreasing. It was found that with increasing the amount of kaolin and decreasing the amount of clay the pore diameter was decreasing. A membrane prepared from 18% clay, 62% kaolin, and 20% binding material and sintered at 1000°C has shown the lowest average pore size of 0.31 μm with porosity, pore density, and flexural strength of 0.22, 4.80 × 1012 m-2 and 12.81 MPa respectively. The membrane pore size and pore density were predicted directly from the particle size distribution of the clay and kaolin and were suitably represented by second-order polynomials. [ABSTRACT FROM AUTHOR]

Abstract: Advanced oxidation process (AOP) followed by microfiltration (MF) was proposed for the removal of crystal violet from aqueous solutions to save energy, time and cost. Fenton''s reagent was used to degrade the dye. The optimal composition of Fenton''s reagent for an initial dye concentration of 100mgL−1 was 1000mgL−1 H2O2 and 100mgL−1 FeSO4 7H2O. A microfiltration membrane (average pore size of 0.31μm) was used to remove the oxidation product at transmembrane pressures of 138, 207 and 276kPa. Small changes in pH (6.4 to 6.2), total dissolved solid (360mgL−1 to 350mgL−1) and density (999.7kgm−3 to 997.1kgm−3) were observed during microfiltration. No dye and dispersed particles were found in the permeate. Thus, 100% dye removal was achieved by the hybrid process. [Copyright &y& Elsevier]

Abstract: We discuss a continuous two-stage cascade ultrafiltration bioreactor-separator system for fragmentation of immunoglobulin G (IgG) by pepsin and purification of F(ab′)2 fragment thus generated. F(ab′)2 is frequently preferred to intact IgG in therapeutic applications due to lower immunogenicity and faster onset of action. The 10kDa MWCO membrane of the first stage bioreactor retained pepsin, IgG and F(ab′)2 while allowing degraded Fc sub-fragments through and the 70kDa membrane of the second stage retained both IgG and F(ab′)2 while allowing pepsin through. Due to this differential retention behavior, the pepsin concentration within the first stage was significantly higher than that in the feed. The first bioreactor therefore primarily carried out IgG digestion while the second stage primarily served as a separator for pepsin and F(ab′)2. The two-stage system was first assessed using pure equine IgG as feed. Under optimized feed and sweep flow rates, 97% IgG conversion with 93% pure F(ab′)2 product were obtained. A mathematical model for the bioreactor system was developed and simulated and experimental data were found to be in good agreement. When the bioreactor system was operated with unpurified equine serum as feed, close to 95% IgG conversion was observed. The F(ab′)2 product obtained from serum showed a single band on SDS-PAGE. The results demonstrated the suitability of the two-step cascade membrane bioreactor for production of F(ab′)2 from both IgG and unpurified equine serum. [Copyright &y& Elsevier]

Abstract: Low-cost ceramic microfiltration membranes were prepared using clay of IIT Guwahati. Two membranes were prepared by paste casting followed by sintering at different temperatures, the first one from clay only (membrane A) and the second one from clay with small amounts of sodium carbonate, sodium metasilicate and boric acid (membrane B). Both the membranes were characterized by TGA, SEM, XRD, water permeability test and acid–base treatment. With the increase of sintering temperature, pore size as well as permeability and flexural strength were increasing while porosity and pore density were decreasing. The overall performance of membrane B was better than membrane A. The average pore size, porosity, pore density and flexural strength of membrane B sintered at 1000°C were 4.58μm, 0.42, 2.06×1010 m−2 and 11.55MPa respectively. This membrane was used for the removal of chromate from aqueous solutions by micellar enhanced microfiltration (MEMF) using cetylpyridinium chloride (CPC). 100% rejection of chromate ions were obtained at a feed ratio (CPC/chromate) of 10. Based on raw material prices, the membrane cost was estimated to be $19/m2. The prepared low-cost membrane showed good promise for the treatment of wastewater containing such heavy metals. [Copyright &y& Elsevier]

In this work, the performance of a commercially available aquaporin HFFO membrane was studied for concentrating the sugarcane juice by adopting appropriate UF pretreatment technique. The influences of draw and feed solution flowrates, draw concentration and its direction of flow such as co-current or counter-current on water and reverse solute flux was evaluated in batch mode. The specific reverse solute flux for counter-current mode was found to be less compared to co-current mode of operation. Improved draw solution (NaCl) flowrate increased the water flux with reduced specific reverse solute flux. The FS concentration ratio was 1.65 within 12 min of batch FO operation by using 100 g L-1 draw solution. Membrane fouling was studied systematically with appropriate membrane cleaning strategy. The effect of UF clarified and raw sugarcane juice on FO membrane fouling was calculated and it was found that raw sugarcane juice led to severe membrane fouling that reduced water permeability after 60 min of operation. The membrane fouled by UF clarified juice was able to regenerate by DI water wash for 30 min, however in the case of membrane fouled by raw juice, an additional 0.1 M NaOH wash was required. [ABSTRACT FROM AUTHOR]

• LaPO 4 coated alumina based ceramic UF membrane was prepared. • Sugarcane juice clarification was carried out using this membrane. • Clarified sugarcane juice properties confirmed a better quality juice. • Innovative cleaning strategy using physical and chemical cleaning was implemented. • Stability of filtered juice for both feed and permeate over 7 weeks at 4 °C studied. The present work explores the possibility of employing rare earth phosphates deposited alumina substrates for ceramic membrane applications. Multichannel porous alumina supports are coated with Lanthanum phosphate nanofibrils of thickness 6 µm by sol-gel deposition technique. The performance of lanthanum phosphate coated ultrafiltration (UF) membrane for sugarcane juice clarification was studied by measuring polyphenol oxidase (PPO) enzyme, bacteria removal efficiency and permeate flux decline profile. The PPO enzyme activity was observed to be lower by 70% in permeate along with a less bacterial presence. The analysis of sucrose loss with time is also studied for raw sugarcane juice, clarified and limed sugarcane juice. A hybrid cleaning strategy involving an innovative brushing action on the membrane surface for physical cleaning combined with chemical cleaning was implemented in this study. The fouled membrane was analyzed by FESEM, EDX, and FTIR. Shelf-life study of feed and permeate confirmed that permeate was more stable than the feed. The experimental results conclude that raw sugarcane juice clarification using lanthanum phosphate coated UF membrane was viable with the use of innovative physical cleaning method as proposed in this study. [ABSTRACT FROM AUTHOR]

• Cynodon dactylon biomass is an abundant and low-cost biological resource. • XRF analysis confirmed the presence of high alkali which might form molten salts. • Kinetic parameters were estimated to understand pyrolysis reaction mechanisms. • Py-GC/MS analysis confirmed formation of high hydrocarbons and phenolics at 550 °C. • Py-FTIR analysis confirmed majority of gases generated within 4−15 s Cynodon dactylon (DG) is a biological resource available in abundance across the world; and has the capability to yield sustainable renewable fuels and fine chemicals. The present study explored the bioenergy potential of DG biomass by evaluating its physicochemical properties, pyrolysis characteristics, and kinetic behaviouer with thermodynamic analysis (TD) for the first time. The physicochemical outcome established its bioenergy potential towards sustainable energy production. The thermal decomposition study of DG biomass was carried out in a thermogravimetric analyser (TGA) at dynamic heating rates (10, 30 and 50 °C min−1), under nitrogen atmosphere while Py-GC–MS was executed to understand the pyrolysis behaviour. The thermal decomposition profile of the DG biomass established multistage degradation, which is linked to the diverse components in its structure. The average apparent kinetic energy was found to be 208.89, 220.43, 211.90, 213.66, 214.28 and 192.30 kJ mol−1 for Kissinger-Akahira-Sunose (KAS), Ozawa-Flynn-Wall (OFW), Friedman (FM), Starink (ST), Distributed Activation Energy Model (DEAM), and Vyazovkin (VZ). Py-GC–MS results revealed that formation of phenolics, aromatic hydrocarbons and ketones in the temperature range 450–650 °C were increased while formation of cyclopentanones, acids, esters and other oxygenated compounds were reduced. Finally, Py-FTIR study confirmed that the majority of functional groups generated in the range of 4 −15 s. [ABSTRACT FROM AUTHOR]

• Recent advances on microalgal biomass to bioenergy conversion process. • Waste derived from algal biofuel conversion process towards value-added co-products. • Validation of zero-waste microalgal biorefinery under circular bioeconomy. • Technoeconomic and life cycle assessment of microalgal biorefinery approach. • Mixed-biomass feedstocks a solution for sustainable operation of biorefinery. In view of the globalization and energy consumption, an economic and sustainable biorefinery model is essential to address the energy security and climate change. From this perspective, renewable biofuel production from microalgae along with a wide range of value-added co-products define its potential as a biorefinery feedstock. However, economic viability of microalgal biorefinery at its current state is not considered sustainable. Reduce, recycle, and reuse of waste derived from algal bioenergy conversion process will lead to an energy efficient and sustainable zero-waste microalgal biorefinery. This review focuses on three major aspects of zero-waste microalgal biorefinery approach; (1) recent advances on microalgal bioenergy conversion processes (chemical, biochemical and thermochemical); (2) mitigation and transformation of liquid and solid waste and (3) techno-economic analysis (TEA) and lifecycle assessment (LCA). In addition, the study also focuses on the challenges and future perspectives for an advanced microalgal biorefinery model. [ABSTRACT FROM AUTHOR]

• Co-pyrolysis of Samanea saman (SS) seeds and PET was carried out. • Blends of SS and PET produced lower ash and higher volatiles. • SS and PET blend at 3:1 resulted in higher synergistic effect than 1:1 and 5:1. • SS and PET blend at 3:1 required lower activation energy to start reaction. • Five model-free methods were used to calculate kinetic parameters. • Kinetic data show good agreements with experimental data. This work deals with co-pyrolysis of polyethylene terephthalate (PET) with Samanea saman seeds (SS) to understand the kinetics and synergistic effects between two different feedstocks. SS and PET were blended in different ratios (1:1, 3:1 and 5:1) and iso-conversional models such as Kissinger-Akahira-Sunose (KAS), Friedman method (FM), Starink (ST), Ozawa-Flynn-Wall method (OFW), and Coats-Redfern method (CR) were used to calculate the kinetic parameters. Results substantiate assumed hypothesis that blending of SS and PET at 3:1 provided higher synergistic effect and RMS value, which in turn indicated maximum formation of hot volatiles during pyrolysis. Kinetic analysis confirmed that individual SS and PET required higher activation energy while blended SS and PET at 3:1 ratio required lower activation energy to start the reaction. The thermodynamic and kinetic analysis confirmed that biomass had complex reaction kinetics which depends on reaction rate as well as its order. [ABSTRACT FROM AUTHOR]

In this research work, agricultural residue was pyrolytically converted in a continuous semi pilot auger reactor. Studies have been carried out with variation in operating conditions such as temperature, and its effect on product yield and quality has been analyzed comprehensively. It was found that with increase in temperature from 400 to 500 ℃, the oil yield increased; however, reduced on further increasing the temperature. The char yield decreased from 50 to 20 wt% and gas yield increased with rising temperature. For cotton stalk pyrolysis, maximum biochar yield of 51% was obtained at 400 ℃, whereas maximum bio-oil yield of 46.5% was obtained at 500 ℃. Maximum gas yield of 55% was obtained with mustard husk feedstock at 700 ℃ temperature. Water content of the cotton stalk bio-oil (35%) was found to be lower than mustard husk bio-oil (79%). The water content in bio-oil was found to enhance with increase in temperature. GC-MS analysis confirmed that different chemical value compounds are present in the bio-oils obtained from both cotton stalk and mustard husk. In addition, the chars obtained had a calorific value of 24.15 MJ/kg for cotton stalk and 24.57 MJ/kg for mustard husk. At 500 °C, biochar showed good thermal stability in TGA analysis and major weight loss occurred in the temperature range of 500–600 ℃. It was also observed that biochar contains high amount of micronutrients and can be used for improving crop productivity by partially replacing synthetic fertilizers. [Display omitted] • Continuous biomass pyrolysis studies were carried out in a semi pilot scale auger reactor. • Effect of temperature on product yields and bio oil chemical value was investigated. • Water content of CS bio-oil was found to be lower as compared to MH bio-oil. • Effect of process conditions on bio char properties was studied. [ABSTRACT FROM AUTHOR]

Developing an efficient photobioreactor (PBR) and reducing freshwater dependence are among the significant challenges for generating 3rd generation biomass feedstock. Addressing these, the present study focused on developing a modified airlift (MoAL) PBR. Its performance was further evaluated and compared with the traditional airlift PBR by cultivating microalgae in dark fermentation spent wash. Lower mixing time and higher interfacial mass transfer coefficient was observed in the MoAL PBR having a perforated draft tube. Experimentally, the MoAL exhibited the maximum biomass concentration of 3.18 g L−1, which was 30% higher than that of the conventional airlift PBR. The semi-continuous operation of the MoAL (with water recycling) achieved the maximum biomass productivity of 0.83 g L−1 d−1, two folds superior to that of batch culture. The comprehensive biomass characterization (proximate, ultimate, and thermochemical) further confirmed its potential for bioenergy application. Considering that, hydrothermal liquefaction of the biomass resulted in a maximum biocrude yield of 31% w/w with a higher heating value (HHV) of 36.6 MJ kg−1. In addition, the biocrude comprised 66.6% w/w lighter fraction (<343 °C), including 21.5% w/w of heavy naphtha, 20.5% w/w of kerosene, and 24.6% w/w of diesel. The results can help develop sustainable technology for simultaneous wastewater remediation and biocrude production. [Display omitted] • Modified airlift (MoAL) photobioreactor was designed for enhanced biomass yield. • Dark fermentation spent wash (DFSW) was found suitable for mixotrophic algal growth. • Biomass concentration was 30% higher in the MoAL than that of the conventional PBR. • Semi-continuous operation of MoAL PBR with water recycling was successfully studied. [ABSTRACT FROM AUTHOR]

[Display omitted] • The shape selectivity of ZSM-5 has been addressed in order to improve bio-oil quality. • ZSM-5′s catalytic activity, structure, and surface chemistry have all been spotlighted. • The acidity of the ZSM-5 catalyst has been thoroughly investigated. • The process characteristics of ZSM-5 catalysts have been described. The oxygenated compounds found in bio-oil limit their application as a transportation fuel. Several studies were reported on eliminating the oxygenated components from bio-oil so as to improve its fuel properties. This work is dedicated to studying the shape selectivity, porosity, structure, acidity of zeolites and their effect in bio-oil and chemicals production. The unified pore size, specific structure, controlled Si/Al ratio, unique channels and circular entrances, mesoporosity, and acidity are the utmost discerning parameters for aromatics production and deoxygenation reaction. The conversion of biomass-derived oxygenates to aromatics using zeolite is subjected to the reactants entering the pore, conversion inside the pore, and diffusing out of the products from the zeolite pores. These approaches were considered for an in-depth understanding of zeolite properties, which will enhance the fundamental understanding of pyrolysis. [ABSTRACT FROM AUTHOR]

• Operative parameters of HTL substantially influence the property and yield of bio-crude. • HTL produced a higher viscosity bio-crude than pyrolysis. • Apart from the temperature, pressure, biomass to solvent ratio altered the bio-crude yield. • Bio-crude generated by HTL scores over pyrolysis except for higher sulphur, yield, and viscosity. • TEA and LCA established variations in yield and properties of fuels with varying operating conditions. An in-depth, comprehensive, and critical review of the hydrothermal liquefaction (HTL) technology for maximum yield of biocrude with enhanced properties has been undertaken. The feedstocks, process parameters, kinetic of HTL for bio-crude production have been systematically examined and collated from a board range of research. In the coverage of Techno-Economic Analysis (TEA) and Life Cycle Assessment (LCA) of HTL of feedstocks, this review overcomes the failure of existing literature to give due weightage to those crucial issues. HTL is introduced by the direct use of wet biomass that eliminates the drying unit, reduction in total expenditure, and conversion of materials into solid and liquid fuels at moderate temperatures (250–400 °C) and pressures (10–35 MPa). The introduction of hot pressurized water results in a lower yield of tar with higher energy proficiency. The biomass is delineated via elemental composition, renewable feedstock potential, and evaluation of dry versus wet biomass feedstocks. HTL is comprehensively reviewed through the process mechanisms, depolymerization reactions of biomass, hydrothermal liquefaction process of dry and wet lignocellulose feedstocks, and the effect of operating parameters. The product(s) description and evaluation, process advancements, energy efficiency, and kinetic investigation in relation to HTL form the final parts of this review. This review is aimed at optimization and commercialization of the HTL technology to meet the demands of the biofuel sector, the researcher working in the thermochemical conversion of feedstocks, and the development of new HTL reactors. [ABSTRACT FROM AUTHOR]

Ionic Liquids (IL) are green solvents and has shown immense potential recently for the solubilisation and dispersion of certain coals. However, the choice of IL is cumbersome owing to its infinite cation and anion combination. Continuum Solvation Models (CSM) can theoretically predict the solvation phenomena of a component in solution. In this work, the continuum solvation model namely Conductor like Screening Model (COSMO) was used to predict the Solid (brown coal) - Liquid (IL) behaviour. Taking the process economics and the nature of ionic liquids into account, 18 ILs were selected from the Sigma Aldrich Catalogue to predict the Solid-liquid Equilibria (SLE) of brown coal in ionic liquid. Initially, the model was benchmarked qualitatively using the data available in literature for coal and conventional solvents such as pyridine and NMP. Thereafter, Gibb's Free Energy of solvation and SLE predictions were performed for these 18 ILs. IL showing the highest solubility was chosen as potential solvent which can disrupt the hydrogen bonding of brown coal and the same was used to predict the solid-liquid-equilibrium. The IL namely 1-butyl-1-methylpyrrolidinium methylcarbonate [BMPYR][CH3CO3] and brown coal gave complementary behaviour in sigma profile which proved that this IL is highly miscible in brown coal. [ABSTRACT FROM AUTHOR]

Highlights: [•] LLE of ammonium and phosphonium ionic liquids-aromatic-aliphatic component reported. [•] Experimental data were correlated with NRTL and UNIQUAC models. [•] Successful prediction using quantum chemical based COSMO-RS model. [•] Low cross contamination between both phases reported. [Copyright &y& Elsevier]

[Display omitted] • Industrial wastewater (IWW) serve as ideal nutrient growth media for microalgae. • IWW requires specific pretreatments and optimization before microalgae cultivation. • Recent advances of IWW treatments through microalgae cultivation are explored. • Microalgal biomass grown on IWWs must be valorized to value-added products. This review article focuses on recent updates on remediation of industrial wastewater (IWW) through microalgae cultivation. These include how adding additional supplements of nutrient to some specific IWWs lacking adequate nutrients improving the microalgae growth and remediation simultaneously. Various pretreatments strategy recently employed for IWWs treatment other than dealing with microalgae was discussed. Various nutrient-rich IWW could be utilized directly with additional dilution, supplement of nutrients and without any pretreatment. Recent advances in various approaches and new tools used for cultivation of microalgae on IWW such as two-step cultivation, pre-acclimatization, novel microalgal-bioelectrical systems, integrated catalytic intense pulse-light process, sequencing batch reactor, use of old stabilized algal-bacterial consortium, immobilized microalgae cells, microalgal bacterial membrane photobioreactor, low-intensity magnetic field, BIO_ALGAE simulation tool, etc. are discussed. In addition, biorefinery of microalgal biomass grown on IWW and its end-use applications are reviewed. [ABSTRACT FROM AUTHOR]

Pyrolysis kinetics and thermodynamic parameters of two non-edible seeds, Pongamia pinnata (PP) and Sapindus emarginatus (SE), and their blend in the ratio of 1:1 (PS) were studied using the thermogravimetric analyzer. Kinetic triplets were determined using both model-free [Starink (STR), Friedman (FRM), Iterative Kissinger-Akahira-Sunose (IT-KAS), Iterative Ozawa-Flynn-Wall (IT-OFW), Vyazovkin (VYZ), and Master plot (MP)] and model fitting Coats-Redfern (CR) methods at three different heating rates 10, 30 and 50 °C/min. Activation energies were 192.66, 179.44, and 163.25 kJ/mol for PP, SE, and PS, respectively. It was found that the blend of the two-biomass (PS) showed promising results with lower activation energy compared to the individual biomass. Thermodynamic parameters (ΔG, ΔS, and ΔH) were obtained using the model-free isoconversional method. The three hidden layers of complex neuron topology are well fitted to the experimental DTG curves by artificial neural network (ANN). The study confirmed that the heating rate had a significant impact on the kinetics and thermodynamic parameters. The reaction mechanism was also in consonance with the experimental data. The study suggests that the PP and SE seeds can be an appropriate feed for pyrolysis, and their blend (PS) can be a viable alternative in optimizing the entire process. [Display omitted] • Both model-free and model-fitting methods are scrutinized. • Kinetics suggested that the binary mixture was suitable for pyrolysis. • The thermodynamics feasibility of the binary mixture is also determined. • Three-layer ANN topology is well fitted with DTG experimental data. [ABSTRACT FROM AUTHOR]

Abstract: This work presents the fabrication of chitosan based ceramic membranes using dip coating technique. Low-cost ceramic supports were prepared from local clay of IIT Guwahati and kaolin with an average pore size of 1093nm and porosity of 0.37. Different ceramic membranes were prepared by varying chitosan concentration and dipping time and were characterized using scanning electron microscope (SEM), air and hydraulic permeability tests. The average pore sizes were in the range of 760–13nm which confirmed that the chitosan impregnated ceramic membranes were applicable for both microfiltration (MF) and ultrafiltration (UF) applications. An increase in both chitosan concentration and dipping time was found to reduce the pore size. The lowest pore size ultrafiltration membrane (pore size: 13nm) was used for the removal of mercury and arsenic from wastewater by polymer enhanced ultrafiltration (PEUF) technique using polyvinyl alcohol (PVA) as the chelating agent. The effects of initial concentrations of mercury, arsenic and PVA on the extent of removal of both the heavy metals were investigated in detail. The efficiency of PEUF was explored in terms of rejection of metals and permeates flux. Almost 100% removals were observed for both 500μgL−1 mercury and 1000μgL−1 arsenic. [Copyright &y& Elsevier]

The viability of the FO process for concentration of sugarcane juice by using a commercially available aquaporin embedded hollow fibre membrane module (HFFO) (active area, 2.3 m2) is presented. NaCl is used as a draw solution (DS), and the selection of suitable DS concentration, flow conditions and flow configuration are observed to be vital aspects to minimize the reverse solute flux (RSF) and energy consumption. Further, the one dimensional mathematical model for the batch and continuous FO process using HF module is developed and validated with experimental data within the error limit of 5% for water flux and RSF. Based on the flowsheet modelling, the method for establishing the optimized FO process is presented. The optimized FO flowsheet presented in this study can concentrate the sugarcane juice from 150 g L−1 to 531 g L−1 with energy consumption of 92.14 WL-1 of permeate and specific RSF = 1.57 g L−1. Further, to commercialize FO process for sugarcane juice concentration application, the selection of suitable food-grade draw solute that can provide high osmotic pressure and low RSF is a very important aspect. • Laboratory-scale FO process was evaluated for concentration of sugarcane juice. • A model for tank mass balance and concentration polarisation has been developed. • Counter-current and co-current were studied with associated parameters evaluation. • Specific energy consumption was 74% higher in batch mode than continuous mode. [ABSTRACT FROM AUTHOR]

Green synthesis of iron oxide nanoparticles (Fe NPs) was prepared using Delonix regia flower extract, and their Photo Fenton like oxidation was performed. The synthesized Fe–NPs were characterized using XRD, FESEM, FETEM, FT-IR, and VSM confirmed the formation both of Magnetite (Fe3O4) and Hematite (α-Fe2O3) nanoparticles. The prepared catalyst was used for the photo Fenton like degradation of Methylene blue (MB) and Congo red (CR) dyes. The optimization of various operational parameters, such as the influence of concentration of catalyst, H2O2, initial dye and initial pH was executed. The results showed that under optimum conditions, about 99% decolorization of both MB and CR dye was accomplished within 10 min. The catalyst was removed by an external magnet, and reuse study showed that there is no notable decrease in the efficacy of the catalyst was observed up to five cycles. The results are exemplifying that the biogenic prepared Fe NPs having high potential for the photo-assisted degradation of both MB and CR in the existence of H2O2. [ABSTRACT FROM AUTHOR]

Multiphasic crystallite complex of the most popular photocatalyst – TiO 2 has consistently shown better UV and/or visible photoactivity than its pristine monophasic counterparts. An identical behaviour is reported in the studies conducted on ZnO as well. This motivated the present study i) to explore the possibility to establish this as generic behavior for all such materials, and ii) to look for a better material with high photocatalytic activity. The choice of niobium pentoxide for the purpose lies in its uniqueness in terms of its existence in different oxidation states and crystalline phases. Additionally it offers a novel and promising alternative to the existing photoactive nanomaterials due to its apposite band gap, band edge location, stability, sorption characteristics and recyclability. Herein, an attempt has been made to prepare niobium pentoxide with different crystalline phases, including mixed, and analyze their photoactivity in UV and visible ranges. The results show that niobium pentoxide, calcined between 500-800°C, crystallizes predominantly in orthorhombic and 900 °C and above in monoclinic phase. The results reveal that under both UV and visible radiation the monophasic (monoclinic phase) niobia has high photoactivity as compared to the other phases in degradation of aqueous probe pollutant. This result is contrary to the expected result. The samples have been characterized by X-ray diffraction(XRD), UV-VIS spectroscopy (UV-VIS DRS), X-ray photoelectron spectroscopy(XPS), photoluminescence(PL) spectroscopy, transmission electron microscopy(TEM), and scanning electron microscopy(SEM) to arrive at a conclusive explanation of the results. The sorption characteristics of the hydrocolloid system, among others, have been found to be responsible for this behavior. • Orthorhombic, monoclinic and pyrochlore niobia phases tested for photocatalytic activity. • Monoclinic niobium pentaoxide showed large activity in both UV and visible irradiation. • Oxygen vacancies played an important role in enhancing the photoactivity of samples. • Role of Zeta potential in enhancement of photocatalytic activity revealed. [ABSTRACT FROM AUTHOR]