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The current research work is to investigate the photocatalytic efficiency and degradation of ciprofloxacin using WO3/TiO2 nanoparticles under visible light irradiation. The nanoparticles of tungsten trioxide (WO3) and its composite with titanium dioxide (TiO2) i.e. WO3/TiO2 was prepared by hydrothermal method. Four basic characterizations were performed to study the prepared sample materials. To study the morphology of the prepared samples, scanning electron microscopy (SEM) was used. The results of SEM clearly showed that tungsten trioxide (WO3) has Rectangular shaped structure. The average size of the pure Tungsten trioxide nanoparticles was about 40–540 nm. The composite of WO3/TiO2 has spherical structure. The reason behind that was the addition of TiO2 in WO3 changes the morphology of pure WO3, and transformed the rectangular structure to a spherical structure. The presence of TiO2 changes the position and orientation of the nanorods in all possible directions. For the detailed analysis of the functional groups present in these samples, band gap, and optical properties of these samples, Fourier transform infrared spectroscopy (FTIR), ultraviolet visible (UV–VIS) spectroscopy and Photoluminescence (PL) emission spectroscopy was used. UV–Vis spectroscopy results showed that the bandgaps of prepared catalysts vary within the range of 2.76 – 2.5 eV. This decrease in bandgap is directly related with the concentration ratio of TiO2 in WO3. The maximum excitation wavelength observed at 440 nm. The maximum degradation efficiency was at 2% of WO3/TiO2 composite catalyst due to unique morphological structure and increase rate of photo absorption. [ABSTRACT FROM AUTHOR]

In this paper, the bismuth vanadate and the composite of bismuth vanadate BiVO4 with nickel ferrite BiVO4/NiFe2O4 is aimed to be synthesized using hydrothermal method for the effective degradation of methylene blue. The concentration of nickel ferrite is varied from 1 to 5%. The morphological, structural, and the optical properties of the prepared samples are studied using X-ray diffraction (XRD), Scanning electron microscope (SEM), Photoluminescence (PL) spectroscopy, and Ultra-violet (UV) spectroscopy. The photocatalytic activity of the prepared photocatalyst is performed under visible light. The composite of BiVO4/NiFe2O4 4% efficiently degrade 99% of methylene blue after 90 min from 100-ml solution under visible light. This paper explains the synthesis of bismuth vanadate and it is composite with nickel ferrite BiVO4/NiFe2O4 and give information about the structural and morphological of these synthesized materials. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate the impact of an anionic precursor [N² gas and triethyleneamine (TEA) as nitrogen dopant source] to prepare anionic doped ZnO thin films surface morphologies, via a novel route - hydrothermal solution deposition at low temperature. The effect of dopant concentration under both with and without pH control was studied. The less populated doped ZnO crystal nearly had the same band gap as compared to undoped ZnO thin films. The photocatalytic activity of selected doped ZnO thin films were studied for the degrdation of 10 mg L-1 Methylene Blue under UV irradiation of 254nm. Based on the 1 st order reaction rate constant results the morphology N2:S2-MS has shown highest degradation followed by N:S1-MS. Overall, the photocatalytic activity order is N2:S2-MS > N:S1-MS > N:S2-CG > N:S1-CG. In general, a significant variation in surface morphologies, crystal size and population, porosity and orientation were observed. This tailored-made variation enabled the doped ZnO thin films to successfully degrade the waste methylene blue effluents. [ABSTRACT FROM AUTHOR]

The natural gas liquefaction process occupies a considerable part of the energy consumption in the LNG industry chain, and efficient optimisation methods should be developed to improve the economic and environmental performances of this process. In this work, a new optimisation strategy based on the particle swarm optimisation (PSO) algorithm and bisection method was developed to optimise the propane precooled refrigerant process (C3MR). In the proposed optimisation strategy, the molar fractions of the mixed refrigerant (MR) components were directly adopted as variables in the PSO algorithm, and the MR flow rate was independently adjusted by the bisection method to satisfy the minimum temperature approach constraints. The results show that the optimal operating conditions reduced the energy requirement of the C3MR process by 4% and decreased the consumption of MR by 31.9%, compared to traditional using the flow rates of MR components as variables. The correlations among the properties of key streams were calculated based on the intermediate results of the proposed method and visualised with the heat map. The results show that the energy requirement of the C3MR process decreased with the increase of the low boiling temperature components and increased with the high boiling temperature components of MR. • A new strategy based on PSO algorithm and bisection method was proposed. • Directly taken the molar fractions of MR components as decision variables. • The energy consumption of the C3MR process was reduced by 4%. • The requirement of MR was decreased by 31.9%. • Using a heat map to analyze the correlations among the properties of key streams. [ABSTRACT FROM AUTHOR]