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In the present work, CdFe2O4/Al2O3 magnetic nanocomposite photocatalyst is successfully synthesized by simple sol-gel auto-combustion method. The role of this sample is studied as a photocatalyst. The influence of Al2O3 concentration with CdFe2O4 on the photocatalytic property is also studied. We have considered three weight percentage of Al2O3, 5%, 10%, and 20% with CdFe2O4. All the samples are characterized with X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) with selected area electron diffraction (SAED), vibrating sample magnetometer (VSM), UV-Visible, and photoluminescence (PL) spectroscopy techniques. The 10% composite sample showed the lower particle size, higher surface area, enhanced porosity, higher saturation magnetization, and considerable band gap as compared to that of 5% and 20% CdFe2O4/Al2O3 as well as bare CdFe2O4 nanoparticles. The photocatalytic activity of the sample is evaluated towards the degradation of the xylenol orange (XO) dye under UV light. The degradation process of the dye is monitored spectrophotometrically. The performance in terms of removal efficiency is studied by varying the contact time, dye concentration and amount of catalyst. Among the three concentrations of Al2O3, the 10% weight concentration of Al2O3 with CdFe2O4 is found to be the optimal concentration and showed the higher degradation rate. After 30 min photocatalytic reaction, the degradation rate is 92.29% for 10% CdFe2O4/Al2O3 and for bare CdFe2O4, it is 85.79%. This work provides a new reference for designing Al2O3-based spinel ferrite nanocomposites and their role in wastewater management. [ABSTRACT FROM AUTHOR]

Alumino‐silicate sulphate sodalite (Nosean), Na8 [AlSiO4]6(SO4)7H2O, was first time successfully synthesized from waste coal fly ash by alkali fusion followed by hydrothermal method. This synthesized Nosean was characterised by FT‐IR, XRD, TGA/DTA, MAS‐NMR, SEM, TEM and BET surface analysis. This paper first time reports the possibility of competitive removal efficiency of Murexide dye (MD) by adsorption and photocatalytic degradation using Nosean. The removal of Murexide dye by adsorption onto Nosean was tested by applying Langmuir's and Freundlich adsorption isotherm along with evaluating the kinetic parameters. Nosean was successfully used for photocatalytic degradation of MD under UV‐Visible light irradiation. The degradation mechanism for MD was established by HPLC‐MS technique and shows various degradation products. Further the recyclability of the photocatalyst, Nosean, was studied up to five runs. [ABSTRACT FROM AUTHOR]

A novel fly ash supported NiO (FA-NiO) nanocomposite solid heterogeneous catalyst has been prepared by impregnation of Ni(NO3)2 · 6H2O on thermally activated fly ash (FA) support. FT-IR spectroscopy, X-ray diffraction analysis, scanning electron microscopy, TEM and BET techniques were employed to characterize the catalyst. The catalytic adeptness of FA-NiO was tested and optimized in xanthene formation. Catalyst gave very high yield and good purity. Stability of the catalyst could be promising as it easily recovered and reused giving a similar yield up to four cycles. FA-NiO is an efficient catalyst providing an environmentally clean process for xanthene formation and for developing a revolutionary way to use the majority of waste fly ash. Further, we have also performed docking simulation between 1ONF and a xanthene molecule to evaluate binding orientation and affinity of the ligand. [ABSTRACT FROM AUTHOR]

Hydrothermal synthesis and comparative gas sensing properties of nanocrystalline ZrO2, 5% yttrium doped ZrO2 (5%Y/ZrO2) and silver coated 5% yttrium doped ZrO2 (Ag-5%Y/ZrO2) and their thick films were reported here for the first time. The obtained polycrystalline products were analyzed by various physical investigative techniques including XRD, TEM and BET surface area. Screen printed thick films of ZrO2 and modified ZrO2 oxides were prepared for gas sensing properties of most toxic combustible and hazardous gases CO, CO2, H2, Cl2, NH3 and H2S at different operating temperatures ranging from 50 to 400 °C. This work investigates the use of ZrO2, 5%Y/ZrO2 and Ag-5%Y/ZrO2 thick film as a gas sensor and the annealing temperature considerably affects the sensitivity of these metal oxides towards NH3 and CO2 gases. The statistical analysis for gas sensitivity towards synthesized catalyst was also carried out. Further, metrological study of Ag-5%Y/ZrO2 sensor as a function of relative humidity (RH) and light intensity with various concentration of CO2 gas is also studied. [ABSTRACT FROM AUTHOR]

This paper for the first time reports the conversion of coal fly ash into intense blue ultramarine via thiocyanate aluminosilicate sodalite Na8[AlSiO4]6(SCN)2. The possibility of stepwise and systemic conversion of thiocyanate aluminosilicate sodalite into intense blue ultramarine had never been previously demonstrated. The ultramarine analogs of various colors have been prepared by structure conversion of thiocyanate aluminosilicate sodalite by calcination (500–950°C). The products obtained are characterized by various investigative techniques including Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, X-ray diffraction (XRD), UV-visible spectroscopy, scanning electron microscopy (SEM), electron spin resonance (ESR) spectroscopy. Surface morphology is studied by the SEM technique. Elemental analysis is carried out with the help of EDAX. Results of ESR have been reported and interpreted. Ultraviolet and Raman spectroscopic analysis gave clear evidence of conversion of SCN−toand further on into. These extensive characterizations showed that the ultramarine pigment is good enough and that the sodalite framework is thermally highly stable with its structure undisturbed even at 950°C. [ABSTRACT FROM AUTHOR]

The CdO and modified CdO nanoparticles were synthesized using hydrothermal method. The absorption spectra, crystal phase, surface morphology, particle size, and surface area of CdO and modified CdO nanoparticles were studied by UV–DRS, FT-IR, XRD, SEM, TEM, TGA, PL, and BET surface area analysis. The present paper reports adsorption technique for the removal of chromium (VI) using CdO and modified CdO nanoparticles. The operating variables such as adsorbent dose, nature of adsorbent, adsorbate concentration, contact time, and pH were optimized. The technique was found to be highly useful and cost effective for removal of chromium (VI). The Langmuir and Freundlich models were evaluated using the experimental data and result showed that the Freundlich isotherm fit better than the Langmuir isotherm. [ABSTRACT FROM PUBLISHER]

This study investigated the chemical modification of F-class coal fly ash (CFA) to an iodate enclathrated aluminosilicate sodalite, Na8[AlSiO4]6(IO3)2, cubic P43n, has been synthesized by hydrothermal treatment followed by fusion of CFA with NaOH. The fused mass was mixed with excess NaIO3 and hydrothermally treated at 100°C. Infrared spectroscopy, X-ray diffraction, Scanning electron microscopy, and inductively coupled plasma spectroscopy methods were used to characterize the obtained sodalite. Sorption behavior of heavy metals (Cd2+, Pb2+, and Zn2+) from aqueous solution on iodate sodalite was examined. The Freundlich and Langmuir isotherms are evaluated for iodate sodalite. These models were fitted to the curves of heavy metals ion solutions to estimate the Freundlich (Kf) and Langmuir (Qo) adsorption parameters. These values followed the same trend of the batch experiments. The maximum sorption capacity of sodalite increased in the order Pb2+>Cd2+ >Zn2+ at the same condition. The effect of different parameters, such as contact time, and temperature were also investigated. The present investigation also revealed that iodate sodalite as sorbents can serve as low-cost adsorbent with higher sorption capacities towards heavy metals. [ABSTRACT FROM AUTHOR]

We report here the synthesis of visible light sensitive PbO and Ni doped PbO nanoparticles by hydrothermal method and characterized by UVDRS, photoluminescence spectroscopy (PL), FTIR, X-ray diffraction (XRD), SEM, EDAX and TGA. Further an efficient approach has been developed for degradation of methyl blue (MB) in aqueous medium. The photodegradation of dye was monitored as a function of dye concentration, pH and catalyst amount has been determined. The reduction in the chemical oxygen demand (COD) revealed the mineralization of dye along with colour removal. [ABSTRACT FROM AUTHOR]

One-pot synthetic gallosilicate nitrate cancrinite (CAN) framework topology have been synthesized under hydrothermal conditions at 100 oC. The synthesized product was characterized by, X-ray powder diffraction, IR, Raman and 29Si, 23Na MAS NMR spectroscopy, SEM and thermogravimetry. The crystal structure refinement of pure nitrate cancrinite has been carried out from X-ray data using Rietveld refinement method. Gallosilicate cancrinite Na8[GaSiO4]6(NO3)4(H2O)6 crystalline hexagonal with space group P63 and a = 12.77981 Å (2), c = 5.20217 Å (1), (Rwp = 0.0696 Rp = 0.0527). The results by MAS NMR spectroscopy confirmed the alternating Si, Ga ordering of the gallosilicate framework for a Si/Ga ratio of 1.0. A distribution of the quadrupolar interaction of the sodium cations caused by the enclatherated water molecules and motional effects can be suggested from the 23Na MAS NMR. Thermogravimetric investigation shows the extent of nitrate entrapment, stability within the cancrinite cage and decomposition properties. SEM clearly shows the hexagonal needle shaped crystals of nitrate cancrinite. [ABSTRACT FROM AUTHOR]