One-step synthesis of zinc-encapsulated MCM-41 as H2S adsorbent and optimization of adsorption parameters

The nano-sized structure of well-ordered Zn@MCM-41 adsorbent was synthesized through a direct hydrothermal method using CTAB as a structure-directing agent in an ammonia aqueous solution with different amounts of zinc acetylacetonate which were inserted into the structure-directing agent's loop during the synthesis. The XRD, HRTEM, and N2 adsorption-desorption isotherms were used to characterize the prepared ZnO functionalized mesoporous silica samples. As a result, the presence of ZnO in highly-ordered MCM-41's pore was proved as well as maintenance of the ordered mesostructure of MCM-41. The materials were possessed with a high specific surface area (1114-509 m2.g-1) and a large pore diameter (4.03-3.27 nm). Based on the obtained results from the adsorption of H2S gas in a lab-made setup, the Znx@MCM-41 showed the superior ability to increase of ZnO amount up to 7 hours as a breakthrough point.

Antifouling and antibacterial behavior of polyethersulfone membrane incorporating polyaniline@silver nanocomposites

Nanocomposites with antibacterial properties were synthesized through in situ reduction of silver ammonia aqueous solution (Ag(NH3)2OH) on polydopamine coated polyaniline (PANI) nanofibers.

Synthesis of TiO2 nanoparticles in the PAMAM hydrogen network template

Intramolecular nanocavities in polyamidoamine (PAMAM) are usually used as a good template to synthesize nanoparticles. In this paper, TiO2 nanoparticles were prepared successfully by the interspaces of the hydrogen network between PAMAM. The possible mechanism was that PAMAM could form the steady microspheres with many interspaces in ammonia aqueous solution at pH=10. The interspaces of the hydrogen network could act as the template for preparing TiO2 nanoparticles. The results were proved by transmission electron microscopy (TEM) and X-ray diffraction (XRD).

Fabrication and Characterization of Amine Compounds Synthesized from Carbon Dioxide and Ammonia Water Using Transition Metal Doped TiO2

Capture and reforming fume gases from atmosphere became an ultimate task recently. Photocatalytic reduction to useful compounds is a key to the future. Photoinduced reduction of carbon dioxide and ammonia aqueous solution into amine compounds at room temperature and atmospheric pressure using transition metal doped titanium dioxide is reported in this paper. UV-visible spectra showed a high absorbance at 200 nm wavelength which is a characteristic of urea. High Performance Liquid Chromatography revealed presence of amine compounds and urea was found a main product of photocatalytic reaction.

Dehydration and volatilization non isothermic kinetic of the solid state aluminium 8-hydroxyquinolinate

Al(C9H6ON)3.2.5H2O was precipitated from the mixture of an aqueous solution of aluminium ion and an acid solution of 8-hydroxyquinoline, by increasing the pH value to 9.5 with ammonia aqueous solution. The TG curves in nitrogen atmosphere present mass losses due to dehydration, partial volatilisation (sublimation plus vaporisation) of the anhydrous compound followed by thermal decomposition with the formation of a mixture of carbonaceous and residues. The relation between sublimation and vaporisation depends on the heating rate used. The non isothermic integral isoconventional methods as linear equations of Ozawa-Flynn-Wall and Kissinger-Akahira-Sunose (KAS) were used to obtain the kinetic parameters from TG and DTA curves, respectively. Despite the fact that both dehydration and volatilisation reactions follow the linearity by using both methods, only for the volatilisation reaction the validity condition, 20<= E/RT<= 50, was verified.