Ultra-deep oxidative desulfurization of fuel with H_2O_2 catalyzed by phosphomolybdic acid supported on silica

A highly active catalyst of phosphomolybdic acid ~HPMo） was prepared and applied in the catalytic oxidative desulfurization （CODS） system. The catalyst was characterized by FT-IR, XRD, XPS and superconducting NMR. The influences of rn（catalyst）/m（oil）, V（H202）fV（oil）, reaction temperature and reaction time on the fractional conversion of benzothiophene （BT） and dibenzothiophene （DBT） were investigated. GC-MS and micra-coulometric methods were employed to investigate the reaction. The catalyst has high desulfurization activity in the removal of BT and DBT under mild conditions. The recycling experiments indicated that DBT and BT removal could still reach 95.2% and 95.7% after 10 cycles.

Iron Bearing Minerals Flotation from Silica Sand Using Hydroxyl Surfactants

A technological clayey sandstone sample from Wadi Qena locality, Eastern Desert of Egypt, was directed to processing. Fine kaolin and clean silica sand were produced after intensive attrition scrubbing of the sample. To increase the quality of the produced silica, it was subjected to reverse anionic flotation to minimize its iron content. In this respect, conventional flotation tests using three anionic oxyhydryl surfactants namely: sodium dodecyl benzene sulphonate, sodium naphtha sulphonate, and sodium dodecyl sulphate, were tried. Results showed a privilege action for sodium dodecyl sulphate to remove most of the iron oxide content of the sample. A statistical Box-Behnken design was constructed to optimize the process efficiency. It was shown that from a flotation feed contained 360 ppm Fe2O3 and 1190 ppm Al2O3, sand concentrate contained 29 ppm Fe2O3 and 564 ppm Al2O3, was produced. The optimum flotation conditions were 3.86 kg/t sodium dodecyl sulphate dose, 3.22 flotation pulp pH, 1226 rpm impeller speed, and 22.24 L/min airflow rate. Variables interaction effects results showed that flotation separation efficiency was significantly influenced by air flow rate and cell impeller speed of the process.

Simultaneously improved actuated performance and mechanical strength of silicone elastomer by reduced graphene oxide encapsulated silicon dioxide

Herein,graphene oxide(GO)-encapsulated silica(SiO 2)hybrids(GO@SiO 2)were prepared via electrostatic self-assembly of the 3-aminopropyltriethoxysilane(APS)-modified SiO_(2) and GO.The as-prepared GO@SiO 2 was introduced into polydimethyl-siloxane(PDMS)elastomer to simultaneously increase the dielectric constant(k)and mechanical properties of PDMS.Then,the in situ thermal reduction of GO@SiO_(2)/PDMS composites was conducted at 180℃ for 2 h to increase the interfacial polariz-ability of GO@SiO_(2).As a result,the values of k at 1000 Hz are largely improved from 3.2 for PDMS to 13.3 for the reduced GO@SiO_(2)(RGO@SiO_(2))/PDMS elastomer.Meanwhile,the dielectric loss of the composites remains low(<0.2 at 1000 Hz).More importantly,the actuated strain at low electric field(5 kV/mm)obviously increases from 0.3%for pure PDMS to 2.59%for the composites with 60 phr of RGO@SiO_(2),an eightfold increase in the actuated strain.In addition,both the tensile strength and elastic modulus are obviously improved by adding 60 phr of RGO@SiO_(2),indicating a good reinforcing effect of RGO@SiO_(2) on PDMS.Our goal is to develop a simple and effective way to improve the actuated performance and mechanical strength of the PDMS dielectric elastomer for its wider application.

Synthesis and Characterization of SiO_2 Coated γ-Fe_2O_3 Nanocomposite Powder for Hyperthermic Application

SiO2 coated γ-Fe2O3 nanocomposite powder has been successfully synthesized by chemical vapor condensation process and its feasibility on hyperthermic application was investigated in this study. The power loss of SiO2 coated γ-Fe2O3 nanocomposite powder which means the magnetic heating effect under alternative magnetic field was much higher than the single phase γ-Fe2O3 nano powder due to the very fine size under 20 nm and well dispersion in biologically compatible SiO2 matrix. The superparamagnetism and hyperthermic property of SiO2 coated γ-Fe2O3 nanocomposite powder were discussed in terms of microstructural development in this study.

Effect of WOx promoter on Pt/ZrO2-HMS catalysts for n-heptane isomerization： Catalytic performance and kinetics study

Platinated W/Zr mixed oxides supported on mesoporous silica with various amounts of Si/Zr, namely PtWO_3/ZrO_2（[76_TD$IF]x）-HMS, were prepared and studied for n-heptane isomerization reaction at 200–350 C. The various methods such as XRD, XRF, FT-IR, UV–vis DRS, NH_3-TPD, H_2 chemisorption, nitrogen adsorption–desorption, Py-IR, SEM and TGA techniques were used for characterization of these materials. Kinetics of n-heptane isomerization was also investigated under various hydrogen. n-Heptane pressures and the influence of reaction conditions on catalytic performance were studied. The ideal catalytic performance was observed on HMS with 0.6%Pt/12%WO_3/ZrO_2 and Si/Zr = 10.