Supaporn Sangsrichan

Preparation and Characterization of BiVO4 Powder by the Sol-gel Method

Bismuth vanadate (BiVO4) powder was successfully prepared by the sol-gel method. Bismuth nitrate and ammonium vanadate were used as the starting precursors with mole ratio of 1:1 in ethanol media at 70°C for 1 h. The yellow gel was calcined at 400–600°C for 2 h. The phase of BiVO4 powder was characterized by X-ray diffraction (XRD). The morphology and chemical composition of BiVO4 powder were investigated by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDXS). The functional groups of BiVO4 powder was identified by Fourier transform infrared spectroscopy (FTIR) and the surface area of BiVO4 powder was determined by Brunauer, Emmett and Teller technique (BET).

Photocatalytic Degradation of Geosmin by Titanium Dioxide Powder Synthesized by the Hydrothermal Route

Titanium dioxide powder was synthesized by the hydrothermal route with the starting precursors as titanium isopropoxide, ammonium hydroxide and nitric acid. The final of pH value of mixed solution was 1 and treated in the hydrothermal PTFE vessel at 80-100 °C for 3h. The phase of titanium dioxide was characterized by X-ray diffractometer (XRD). The morphology of titanium dioxide was investigated by scanning electron microscope (SEM). The chemical composition of titanium dioxide was examined by energy dispersive X-ray spectrophotometer (EDXS). The photocatalytic degradation of geosmin by titanium dioxide was determined by gas chromatograph coupled with flame ionization detector (GC-FID).

Characterization of bismuth vanadate (BiVO4) nanoparticle prepared by solvothermal method

ABSTRACT Bismuth vanadate (BiVO4) nanoparticle was prepared by solvothermal method. The starting precursors were used as bismuth nitrate pentahydrate (Bi(NO3)3•5H2O), ammonium metavanadate (NH4VO3) and absolute ethanol (C2H5OH). Solution I: Bi(NO3)3•5H2O was dissolved in 2.0 M nitric acid (HNO3) and absolute ethanol (C2H5OH). Solution II: NH4VO3 was dissolved in 2.0 M ammonium hydroxide (NH4OH) and absolute ethanol (C2H5OH). The mixed solutions were stirred for 5 min and left into Teflon-lined stainless steel autoclave treatment at 200°C for 3 and 5 h. The yellow final solution was filtered and dried at 100°C for 24 h. All BiVO4 nanoparticle samples were characterized by X-ray diffractometer (XRD), field emission scanning electron microscope (FESEM), energy dispersive X-ray spectrometer (EDXS) and Fourier transform infrared spectrometer (FTIR).

The Photocatalytic Degradation of Phenol and Chlorophenol onto Bismuth Vanadate Powder Prepared by the Solvothermal Method

Bismuth vanadate (BiVO4) powder was prepared by the solvothermal method. Bismuth nitrate and ammonium vanadate were used as the starting precursors with mole ratio of 1:1. The mixed solution was heated in the solvothermal vessel at 100°C for 2–6 h. The phase of BiVO4 powder was characterized by X–ray diffractometer (XRD). The morphology and chemical composition of BiVO4 powder were investigated by scanning electron microscope (SEM) and energy dispersive X–ray spectroscope (EDXS). The surface area of BiVO4 powder was determined by Brunauer, Emmett and Teller analyzer (BET). The photocatalytic degradation of phenol and chlorophenol onto BiVO4 powder was studied and determined by gas chromatograph (GC).

BiVO 4 Powder Synthesized via the Solvothermal Method

Bismuth vanadate (BiVO4) powder was synthesized via the solvothermal method at 100200 °C for 26h by using acetic acid as solvent without calcination steps. The phase transition of BiVO4 powder was studied by Xray diffraction (XRD). The morphology and chemical composition of BiVO4 powder were investigated by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The functional groups of BiVO4 powder was identified by Fourier transform infrared spectroscopy (FTIR).

Characterization of Diatomite, Leonardite and Pumice

This research studies compositions of diatomite, leonardite and pumice for utilization appropriate to the properties of materials. Chemical compositions of these materials were characterized by X–ray fluorescence spectrometry (XRF) and energy dispersive X–ray spectrometry (EDXS). The silica was major component of these materials. The morphology was investigated by scanning electron microscopy (SEM). Diatomite was cylindrical in shape, leonardite was sheet or flake in shape and pumicewas prismatic in shape. The structure was studied by X–ray diffraction (XRD). It was found that the mineral composition of diatomite, leonardite and pumice showed cristobalite low, quartz and anorthite, respectively. The functional groups were identified by Fourier transform infraredspectrometry (FTIR). The functional group of siloxane was obtained and dominated vibration in these materials. And the vibration of carboxylic, alcoholic and carbonyl groups were obtained in leonardite.

The Photocatalytic Degradation of Methomyl over TiO2 Nanopowder Prepared by the Low Temperature Solvothermal Route

Titanium dioxide (TiO2) nanopowder was prepared by the low temperature solvothermal route with starting chemicals containing titanium isopropoxide, ammonium hydroxide, nitric acid and ethanol in a PTFE–lined autoclave. The final pH of the mixed solution was 1 and treated at 100 °C for 2–6 h. The white precipitated was filtered and dried in an oven at 80 °C for 24 h. The phase transition was characterized by X–ray diffractometer (XRD). Single phase anatase structure was obtained without calcination step. The morphology and particle size of TiO2 nanopowder was investigated by scanning electron microscope (SEM). The average of TiO2 nanopowder size was 80–120 nm. The average particle size increased with temperature and time increased. The photocatalytic degradation of methomyl in natural water was studied by high performance liquid chromatograph (HPLC). The percentage of methomyl was decreased in the presence of 34, 23 and 24 over TiO2 nanopowder prepared by the low temperature solvothermal route at 100 °C for 2, 4 and 6 h, respectively.

Photocatalytic Degradation of 2-chlorophenol over TiO2 Powder

Titanium dioxide (TiO2) powder was prepared by hydrothermal route. Titanium isopropoxide, ammonium hydroxide and nitric acid were used as the starting materials. The final pH value of mixed solution was 1 and treated at 80 and 100 °C for 26h. The phase transition of TiO2 powder was studied by Xray diffraction (XRD). Multiphase of anatase and rutile of TiO2 powder were obtained at 80 and 100 °C for 26h without calcination steps. The morphology of TiO2 powder was investigated by scanning electron microscopy (SEM). The particle was highly agglomerated and irregular in shape with the range of particle size of 0.10.3 μm. The chemical composition of TiO2 powder was examined by energy dispersive spectroscopy (EDS). The element chemical compositions show the characteristic Xray energy level as follows: titanium Kα = 4.51 keV and Kβ = 4.93 keV and oxygen Kα = 0.52 keV, respectively. The photocatalytic degradation efficiency of 2chlorophenol (2CP) over TiO2 powder was determined by gas chromatography (GC). It was found that TiO2 powder prepared by hydrothermal route at 80 °C for 2h was the best efficiency for photocatalytic degradation of 2CP.

Titanium Dioxide (TiO2) Nanopowder Prepared by the Low Temperature Solvothermal Method

Titanium dioxide (TiO2) nanopowder was prepared by the low temperature solvothermal method with starting chemicals containing titanium isopropoxide (Ti(OCH(CH3)2)4), ammonium hydroxide (NH4OH), nitric acid (HNO3) and ethanol (C2H5OH) in a PTFE-lined autoclave. The pH of the mixed final solution was 1 and treated at 100–200°C for 2–6 h. The white powder was filtered and dried in an oven at 80°C for 24 h. The phase transition was characterized by X-ray diffractometer (XRD). The morphology and microstructure were investigated by scanning electron microscope (SEM). The chemical composition was identified by energy dispersive X-ray spectrometer (EDXS). The surface area was determined by Brunauer, Emmett and Teller analyzer (BET).