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This study is focused on the utilization of the limestone from Aceh province, Indonesia, as a raw material for preparing inorganic oxide using a high thermal decomposition method. In this preliminary experiment, the limestone material was powdered, then calcined at a temperature of 900 °C for 4 hours under atmospheric pressure and modified with several concentrations of nickel element (1, 3, 5 wt%). The prepared catalyst was characterized using analytical instruments, namely X-Ray Diffraction (XRD) and Scanning Electron Microscope Energy Dispersive Spectroscopy (SEM-EDS). Based on the diffractogram of XRD, it can be known that the prepared catalyst was dominated by CaO crystals, in which Al2O3 was a minor compound. Characterization of the prepared catalyst using SEM-EDS demonstrated that the catalyst has a homogeneous morphology and uniform particle size. [ABSTRACT FROM AUTHOR]

The fabrication of chitosan-glycine crosslinkedby polyethylene glycol diglycidyl ether (PEGDE) for the removal of metanil yellow has been conducted. Fourier-transform infrared spectroscopy (FTIR), Differential scanning calorimetry (DSC), Scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis were used for PEGDE crosslinked chitosan-glycine (Chi-Gly-PEDGE) characterizations. The addition of glycine and PEGDE slightly changed the crystallinity of chitosan, according to XRD results. The formation of a chitosan-glycine-PEGDE film was confirmed by FT-IR results. According to the DSC data, the addition of glycine reduced the film's thermal resistance while the addition of PEGDE was able to boost that resistance. The adsorption analysis demonstrates that adsorption follows the Langmuir isotherm model with an R2 value of 0.996 and the maximal adsorption capacity of 18.181 mg/g. [ABSTRACT FROM AUTHOR]

ZnO/α-Fe2O3 nanocomposite have been synthesized by a ball milling technique and applied for indigo carmine dye degradation in aqueous solutions. ZnO and α-Fe2O3 with the mole ratio of 1 : 5 were mixed without solvent in a planetary mill at the milling speed of 350 rpm for 2 h. X-ray Diffraction (XRD) and Scanning Electron Microscopy with Energy Dispersive X-ray Spectroscopy (SEM-EDS) were used to characterize individual and nanocomposite samples. Based on XRD results it is known that the average crystallite size of α-Fe2O3, ZnO, and ZnO/α-Fe2O3 nanocomposite determined by using Scherer's formula are 52.40 nm, 39.47 nm, and 47.07 nm. SEM images show that α-Fe2O3 particles are highly homogeneous in shape and size, while the image of ZnO/α-Fe2O3 nanocomposite confirmed the presence of ZnO in α-Fe2O3 surface. Compare to α-Fe2O3 and ZnO, ZnO/α-Fe2O3 nanocomposite showed higher photocatalytic activitiy for degradation of indigo carmine under UV irradiation. Some parameter conditions such as the pH of indigo carmine solution, ZnO/α-Fe2O3 nanocomposite dosage, and indigo carmine concentration also studied in detail. The highest degradation percentage of indigo carmine was obtained by using 250 mg of ZnO/α-Fe2O3 nanocomposite, the initial pH of indigo carmine solution is 1, and indigo carmine concentration is 15 mg/L at the irradiation time under UV light for 120 minutes and 90 minutes under solar light. [ABSTRACT FROM AUTHOR]

Chitosan was modified with glutamic acid and TiO2 in.order to improve chitosan performance for methylene blue removal. Chitosan-Glutamic Acid/TiO2 films (CGATF) were prepared with variations in the composition of chitosan glutamic acid and TiO2. CGATF was characterized by Fourier-transformed infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and Tensile test. FTIR spectra confirm that the carboxyl group in glutamic acid had reacted with the amine group in chitosan. SEM images indicate that there is no significant change in the surface of the film. The addition of glutamic acid has decreased the mechanical properties of chitosan. Based on adsorption study the addition of glutamic acid and TiO2 can increase chitosan performance on methylene blue removal from water. [ABSTRACT FROM AUTHOR]

This work focuses on the preparation and characterization of activated carbon/hematite (AC/α-Fe2O3) composite for use as a photocatalyst in the decolorization of naphthol blue black (NBB) dye under ultraviolet irradiation. The photocatalyst was produced using iron sand as a source of hematite with the addition of 15 % w/w of activated carbon derived from waste coffee grounds using a hydrothermal method. The as-prepared materials were characterized by using the X-Ray Diffraction (XRD), Scanning Electron Microscopy-Energy-Dispersive X- Ray Spectroscopy (SEM-EDS), nitrogen adsorption–desorption (BET) and UV–visible spectroscopy. The AC/α-Fe2O3 composite exhibited a high photocatalytic activity on photodegradation of NBB. The degradation percentage of NBB dye was found to be 80.40 % that was observed at pH 1.0, the amount of photocatalyst is 300 mg, initial of dye concentration is 20 mg L−1 after being irradiated for 120 minutes. This is an improved photo-activity, relative to bare α-Fe2O3 with a lower degradation percentage of NBB dye (50.89%). The AC/α-Fe2O3 composite also can remove the dye-containing wastewater up to 90.59 % and 95.42 % under UV and sunlight irradiation, respectively. [ABSTRACT FROM AUTHOR]