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Microfiltration flat sheet membranes of polyether sulfone (PES) were fabricated by incorporating varying concentrations of polymer and investigated the influence of substituting solvents. The membranes were prepared via immersion precipitation method. Different solvents that included NMP (N-methyl-2-pyrrolidone), DMF (dimethylformamide), and THF (tetrahydrofuran) were used to analyse their effect on the performance and morphology of the prepared membranes. Two different coagulation bath temperatures were used to investigate the kinetics of membrane formation and subsequent effect on membrane performance. The maximum water flux of 141 ml/cm2.h was observed using 21% of PES concentration in NMP + THF cosolvent system. The highest tensile strength of 29.15 MPa was observed using membrane prepared with 21% PES concentration in NMP as solvent and coagulation bath temperature of 25°C. The highest hydraulic membrane resistance was reported for membrane prepared with 21% PES concentration in NMP as solvent. Moreover, the lowest contact angle of 67° was observed for membrane prepared with 15% of PES concentration in NMP as solvent with coagulation bath temperature of 28°C. Furthermore, the Hansen solubility parameter was used to study the effect on the thermodynamics of membrane formation and found to be in good correlation with experimental observation and approach in the present work.

Environmental concerns due to excessive use of synthetic or petroleum-based materials have encouraged scientists to develop novel, sustainable, and multifunctional material using abundant lignocellulosic biomass. In this work, a study was conducted on the isolation of cellulose from wheat straw using two different methods: acidified sodium chlorite and alkaline hydrogen peroxide. A comparative study was carried out based on the yield and properties of extracted cellulose. The final product (after treatments) was characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA) for the identification of properties. Both the treatments isolated pure white color cellulose. However, the yield of cellulose isolated through acidified sodium chlorite treatment (81.4%) was higher than alkaline hydrogen peroxide treatment (79%). Moreover, no huge difference was observed in the crystallinity and thermal properties of extracted cellulose.

Treatment of pandrug resistant (PDR) Escherichia coli strain is the leading causative agent of bovine mastitis worldwide. Hence, becoming a potential threat to veterinary and public health. Therefore, to control the infection new nontoxic, biocompatible antimicrobial formulation with enhanced antibacterial activity is massively required. Current study was planned to synthesize chitosan coated titanium dioxide nanoparticles (CS-NPs coated TiO2). Coating was being done by chitosan nanoparticles (CS-NPs) using ionic gelation method. Aqueous solution of Moringa concanensis leaf extract was used to synthesize titanium dioxide nanoparticles (TiO2 NPs). The synthesized nanoformulations were characterized by using XRD, SEM, and FTIR. X-ray diffraction (XRD) analysis indicated the crystalline phase of TiO2 NPs and CS-NPs coated TiO2 NPs. Scanning Electron Microscopy (SEM) confirmed spherical shaped nanoparticles size of chitosan NPs ranging from 19–25 nm and TiO2 NPs 35–50 nm. Thesize of CS-NPs coated TiO2 NPs was in the range of 65–75 nm. The UV-Vis Spectra and band gap values illustrated the red shift in CS-NPs coated TiO2 NPs. Fourier transform infrared (FTIR) spectroscopy confirmed the linkages between TiO2 NPs and chitosan biopolymer, Zeta potential confirmed the stability of CS-NPs coated TiO2 NPs by showing 95 mV peak value. In-vitro antibacterial activity of CS-NPs coated TiO2 NPs and Uncoated TiO2 NPs was evaluated by disc diffusion method against PDR strain of E. coli isolated from mastitic milk samples. The antibacterial activity of all the synthesized nanoformulations were noted and highest antibacterial activity was shown by CS-NPs coated TiO2-NPs against pandrug resistant (PDR) E. coli strain with the prominent zone of inhibition of 23 mm. Morphological changes of E. coli cells after the treatment with MIC concentration (0.78 μg/ml) of CS-NPs coated TiO2 NPs were studied by transmission electron microscopy TEM showedrigorous morphological defectand has distorted the general appearance of the E. coli cells. Cytotoxicity (HepG2 cell line) and hemolytic (human blood) studies confirmed nontoxic/biocompatible nature of CS-NPs coated biologically synthesized TiO2 NPs. The results suggested that biologically synthesized and surface modified TiO2 NPs by mucoadhesive polysaccharides (e.g. chitosan) coating would be an effective and non-toxic alternative therapeutic agent to be used in livestock industry to control drug resistant veterinary pathogens.

Deca-dodecasil 3 rhombohedral (DDR3) membrane has received much attention in CO2 separation from small gas molecules because of its molecular sieving property and stable characteristics. Therefore, the present work is focusing on the utilization of previously fabricated membrane (synthesized in 3 days as reported in our previous work) to study the effect of hydrocarbons and its durability at the previously optimized conditions. Subsequently, gas permeation study was conducted on the DDR3 membrane in CO2 separation from small gas molecules and it was found that the permeance of H2, CO2, N2, and CH4 decreased in the order of H2 > CO2 > N2 > CH4, according to the increase in kinetic diameter of these gas molecules. Besides, it was observed that the ideal selectivities of the gas pairs decreased in the sequence of CO2/CH4 > CO2/N2 > H2/CO2. On the other hand, it was found that the presence of hydrocarbon impurities in the gas mixture containing CO2 and CH4 has directly affected the performance of DDR3 membrane and contributed to the losses of CO2 permeability, CH4 permeability, and CO2/CH4 selectivity of 39.1%, 14.8%, and 4.2%, respectively. Consequently, from the stability test, the performance of DDR3 membrane remained stable for 96 h, even after the separation testing using CO2 and CH4 gas mixture containing hydrocarbon impurities.