Supakit Achiwawanich

Synthesis of Three-Dimensionally Ordered Macroporous Co/SiO2 Catalysts by Sol-Gel Method

A preparation of novel cobalt-based catalyst on three-dimensionally ordered macroporous (3DOM) silica supporter using poly (methyl methacrylate) monolith as a template has been studied. Monodispersed PMMA colloids were synthesized via an emulsion polymerization, resulting in PMMA spheres with the diameter of 390-400 nm. Two processes were employed for the 3DOM Co/SiO2 catalyst fabrications, a single-stage sol-gel synthesis (SG) and incipient wetness impregnation method (IM) on synthesized 3DOM SiO2. Both catalysts were characterized using X-ray Diffraction (XRD), X-ray Absorption Spectroscopy (XAS), Scanning Electron Microscope (SEM) and specific surface area analysis. The XRD and XAS results showed that the doped Co in the 3DOM Co/SiO2 (SG) were the mix phase of Co(NO3)2 and Co3O4 , while, only Co3O4 was found in the 3DOM Co/SiO2(IM). The SEM micrographs revealed that both catalysts feature periodic macroporous structure with mean pore diameter of 300-350 nm. Specific surface area of the 3DOM Co/SiO2 (IM) and the 3DOM Co/SiO2 (SG) catalysts are 195 m2/g and 286 m2/g, respectively.

Synthesis of Ca-Doped Three-Dimensionally Ordered Macroporous Catalysts for Transesterification

The novel three-dimensionally ordered macroporous (3DOM) CaO/SiO2, 3DOM CaO/Al2O3, and 3DOM Ca12Al14O32Cl2 catalysts for biodiesel transesterification were prepared by sol-gel method. The 3DOM catalysts were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The hierarchical porous structure was achieved; however, only 3DOM CaO/Al2O3 and 3DOM Ca12Al14O32Cl2 catalysts were used for transesterification due to high amount of active CaO. Various parameters such as methanol to oil molar ratio, catalyst concentration, reaction time, and their influence on the biodiesel production were studied. The result showed that 99.0% RPO conversion was achieved using the 3DOM Ca12Al14O33Cl2 as a catalyst under the optimal condition of 12 : 1 methanol to oil molar ratio and 6 wt.% catalyst with reaction time of 3 hours at 65°C.

2,2′-({4-[(4-Nitro­phen­yl)diazen­yl]phen­yl}imino)­diethanol

In the title compound, C16H18N4O4, the molecule assumes an E conformation with respect to the N=N double bond. The aromatic rings are not coplanar, with a dihedral angle of 7.51 (8)°. The nitro group is tilted by 4.71 (11)° relative to the attached benzene ring. In the crystal, molecules are connected through O—H⋯O hydrogen bonds forming a double-stranded chain parallel to the b axis.

3-Amino-benzoic acid-4,4'-bipyridine (2/3).

The asymmetric unit of the title compound, 3C10H8N2·2C7H7NO2, consists of three molecules of 4,4′-bipyridine (bpy) and two molecules of 3-aminobenzoic acid (bza). Two molecules of bza and two molecules of bpy are connected via O—H⋯N, N—H⋯N and N—H⋯O hydrogen bonds, forming forming infinite double-stranded zigzag chains along the c axis. The third molecule of bpy is linked to the chain by weak C—H⋯O interactions. Adjacent chains are linked via π–π interactions [centroid–centroid distances = 3.759 (3)–3.928 (3) Å] involving the pyridine rings of bpy molecules, resulting in a sheet-like structure parallel to (100). These sheets are stacked via C—H⋯π interactions, resulting finally in the formation of a three-dimensional supramolecular structure.

Synthesis of Three-Dimensionally Ordered Macroporous (3DOM) TiO2: Photodegradation Catalyst

Three-dimensionally ordered macroporous (3DOM) TiO2 were successfully synthesized by incorporating colloidal crystal template and sol-gel method using titanium isopropoxide and ethanol as precursors. After calcination at 450°C, the synthesized photocatalyst was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and diffuse reflectance UV-VIS spectroscopy (DR/UV-VIS). XRD results indicated that only anatase was presented. SEM images illustrated highly ordered macroporous structure which was a characteristic for 3DOM materials. The band gap energy of 3DOM TiO2 and nanoparticles TiO2 (NP TiO2) were 3.26 eV and 3.23 eV, respectively. Although the band gap value of 3DOM TiO2 similar to NP TiO2 but the photocatalytic performance of the 3DOM TiO2 were higher than that of commercial nanoparticle TiO2. The result suggested that its ordered porous structure is great advantage for photocatalysis.

Self-Cleaning Finishes on PET and PLA Fabrics Using TiO2 Nanoparticles

PET and PLA fabrics were finished with TiO2 nanoparticles by the pad-dry-cure method to enhance self-cleaning abilities. An acrylate binder was used to improve the fixation of TiO2 on polyester fabrics. The existence of TiO2 on the fabrics was confirmed by SEM and ICP-OES. The TiO2 on the finished fabric could reduce the stains in a higher degree as compared to the unfinished fabric. The dyeing properties of polyester with C.I. Disperse Red 60 were slightly affected by TiO2 nanoparticles in terms of color strength (K/S) and color fastness.

3,8-Dimethyl-4,7-diaza-deca-3,7-diene-2,9-dione dioxime.

The complete molecule of the title compound, C10H18N4O2, is generated by a crystallographic inversion centre at the mid-point of the central C—C bond. The two oxime groups have an E configuration. In the crystal, molecules are linked through intermolecular O—H⋯N hydrogen bonds.

1-(2-Bromobenzoyl)-6,7-(methylene-dioxy)isoquinoline.

In the title molecule, C17H10BrNO3, the mean planes of tricycle and bromophenyl fragments form a dihedral angle of 75.5 (1)°. In the crystal, π–π interactions [centroid–centroid distances = 3.556 (2) and 3.898 (8) Å] between the isoquinoline systems link molecules into stacks parallel to the a axis. The crystal packing also exibits weak intermolecular C—H⋯O hydrogen bonds.