Hu Songqing

Preparation of amino-functionalized Fe3O4@mSiO2 core-shell magnetic nanoparticles and their application for aqueous Fe3+ removal

Fe3O4 nanoparticle with magnetic properties and nanoscale features has provoked wide research interest and great potential application. Herein, a modified Stober and template-removing method was adopted to prepare magnetic mesoporous silica nanoparticles (MSNs), comprising a Fe3O4 core and a mesoporous silica shell. The shell was functionalized by amino-groups with tunable removal efficiency for aqueous heavy metals ions. Structural and magnetic properties were characterized by XRD, SEM, FT-IR, vibrating sample magnetometer (VSM) and BET (Brunauer-Emmertt-Teller) techniques. Also, the adsorbing efficiency for heavy metal ions was measured by UV-vis spectrometry. Results revealed that the pure magnetite is cubic with a side length of 40 - 70nm, while the silica-coated magnetite is spherical with a diameter of 220-260nm. The mesoporous silica shell has an average pore size of 2.6nm and a high surface area of 675m2·g-1, which lead to a large adsorption capacity for Fe3+ (up to 20.66mg of Fe per g of adsorbent). Moreover, rapid magnetic separation and regeneration of as-prepared adsorbent were achieved conveniently. The distinctive structure and the heavy metal ions removal property of magnetic nanocomposites reflect their prospective application in water treatment.

Experimental and theoretical research on catalytic synthesis of thiophene from furan and H2S

The yield of thiophene from furan and H2S was investigated using selected catalyst carriers (alumina, active carbon and silica gel) and active ingredients (silicotungstic, phosphomolybdic and phosphotungstic acids) to obtain the optimized synthesis parameters. The experimental results indicated that the yield of thiophene reached a maximum when the supported catalyst was alumina and the active ingredient was phosphotungstic acid. Furthermore, the reaction mechanism of the optimized reactive system was studied by the density functional theory (DFT) method. The calculated energy profile indicated that there were four transition states in the reaction process.