Advanced Materials Research Vols. 396-398

Abstract: Phenol was synthesized from the hydroxylation of bromobenzene, which was prapared by reacting benzene with bromine. In the benzene bromination reaction, HZSM-5 (Si/Al = 400/1) was found to be a stable catalyst, which catalyzed the stoichiometric reaction of benzene with bromine. More than 90% of bromobenzene selectivity was reached over HZSM-5 and the byproduct was dibromobenzenes. In the second reaction, bromobenzene reacted with a cataloreactant to form metal bromide and phenol. This is a catalytic as well as stoichiometric reaction between bromobenzene and the metal oxide. It was found that only the supported highly dispensed metal oxide was reactive to the bromobenzene hydroxylation reaction. In this investigation, 10mol%CuO/SiO₂ was found to be the most active cataloreactant for bromobenzene hydroxylation reaction.

Abstract: Paralled flaw precipitation method has been employed to synthesize nanostructured ZnO. The prepared photocatalyst was characterized by BET, XRD. The paper reveals that Methyl Orange (MO) can be decolorized effectively in ZnO suspension system under UV irradiation. The optimal loading of photocatalyst in our experimental condition for the decolorization of MO is 1g/L. The present study, on the base of Langmuir-Hinshelwood mechanism, illustrates that the decolorization reaction is a pseudo first order kinetic model with the limiting rate constant of 8.48×10-2 mgL-1min-1 and equilibrium adsorption constant 0.335 L/mg, respectively.

Abstract: Mesoporous catalysts [HPMo][HTAC]2/SiO2 with different loading amount of [HPMo][HTAC]2 were prepared by sol–gel method. The catalysts were characterized by XRD, FT-IR, SEM and pore structure parameters. The catalytic activity for the oxidative desulfurization of benzothiophene (BT) and dibenzothiophene (DBT) was evaluated using hydrogen peroxide as an oxidant. Results of the charaterization show that the Keggin structures of all the loaded catalysts were kept and [HPMo][HTAC]2 was highly dispersed on the surface of SiO2. The desulfurization rate of the catalyst 20%[HPMo][HTAC]2/SiO2 can be up to 91% for DBT and 75% for BT in 2 h.

Abstract: The plant oil-based epoxy materials are considered as environment-friendly, biodegradable, renewable raw materials, potentially replacing petrochemical-based epoxy materials in many fields. Soybean oil methyl esters (SOME) were epoxidized with Prileshajev and Chemo-enzymatic reactions. The highest epoxy oxirane achieved by Prileshajev epoxidation was only 4.42%, however, it could reach 5.63% by chemo-enzymatic epoxidation. The stability of oxirane by chemo-enzymatic epoxidation was better than that by Prileshajev epoxidation. The results showed that the chemo-enzymatic method was extremely efficient in the synthesis of epoxides from unsaturated methyl esters.

Abstract: CNT (Carbon nanotube)-supported Fe2O3 combustion catalyst was prepared via a sol-gel method in order to promote the thermal decomposition of ammonium perchilorate (AP). XRD (X-ray diffraction) analysis proved that the product was nanosized hexagonal α-Fe2O3 loading on carbon substrate. TG (Thermogravimetry) and DTA (Differential Thermal Analysis) tests showed that Fe2O3/CNT could accelerate AP thermal decomposition at relatively low temperature. It was suggested that the improvement of the catalytic activity was associated with the dispersion of Fe2O3 nanoparticles and the enlargement of active region.

Abstract: A new type of gold catalysts have been prepared by supporting gold colloids on layered double hydroxide (MgAl-LDHs) carrier at different pH values. CO oxidation reaction at room temperature was used as probe reaction to test the oxidation activity of the gold catalysts, and X-ray diffraction (XRD), X-ray fluorescence (XRF) and high resolution transmission election microscopy (HRTEM) techniques were used to characterize the physical phase, gold loading, morphology as well as mean diameter of gold particles and particle distribution of the represented gold catalyst samples. Influence of pH value during synthesis of the catalysts on the gold loading and oxidation activity of the gold catalysts was studied. Besides these, the stability of the gold catalysts was investigated by thermal treatment and exposure to air and natural light for a long time. The results indicated that gold colloids can be attached on the carrier easily when pH value was controlled between 6-7, and gold loading in the gold catalysts prepared in this condition was above 1.3wt.%. 100% conversion of CO at room temperature can be obtained when the fresh prepared catalysts had been calcined in the air for 2 h at 473 K. The HRTEM images of the gold catalyst showed that the gold particles were highly dispersed on the surface of the carrier, and the average size of the gold particles was 3.2 nm. After thermal treatment at 723 K or storage 4 weeks in air, gold particle size was still kept less than 5nm and the conversion of CO at room temperature over the aged catalysts achieved 100%.

Abstract: The article mainly introduct the development and application of shotcreting castable for metallurgical steel ladle. The shotcreting castable mainly use tabular alumina, white fused corundum, fused spinel, aluminate cement, alumina micro powder, fused magnesium as raw material, After studied by the workability and physical properties of gunning machine, it is proved by application in steel ladle, the shotcreting castable has a good workability, with higher adhesive rate, faster hardening speed, better thermal shock resistance and stronger erosion resistance ability. So the shotcreting castable has a higher service life.

Abstract: It has been found that the photocatalytic activity of ZnO toward the decolorization of Methyl Orange solution can be greatly improved by loading Ag on the surface of ZnO using a photodeposition method. The photocatalysts were characterized by X-ray diffraction(XRD), UV-Vis diffuse reflectance spectroscopy and X-ray photoelectron spectroscopy(XPS), respectively. 0.5%Ag/ZnO demonstrates 2.13 times the photocatalytic activity of pure ZnO.

Abstract: The catalysts of HPMo/SiO2 modified with Ce3+ were prepared by the sol-gel method. The catalysts were characterized by FT-IR, XRD, SEM and pore structure parameters and evaluated for the oxidative desulfurization of model fuel using hydrogen peroxide as an oxidant. Results showed that the catalysts kept the Keggin structures and the introduction of CeCl3 promoted the high dispersion of MoO3 over SiO2 and increased the specific surface area of the catalysts. Under the optimal reaction conditions, the desulfurization rate for dibenzothiophene (DBT) and benzothiophene (BT) achieved 98.9% and 43.4%, respectively.

Abstract: The inhibitor was high consumption of low-efficiency of depressant in the separation of copper- molybdenum is bottleneck, which restricts the improvement of the Cu-Mo separation technology. This paper study the Dexing copper-molybdenum flotation separation by using a new small molecule inhibitors named pseudothiohydantoin(DLC) and single-factor experiments were employed to confirmed the system of reagent. Test results indicate that DLC can make a high inhibit effect with a low consumption. Eventually, use close circuit tests to verify the inhibitor’s ability and the technical indexes such as the grade of Mo concentrate 26.17% and the recovery 89.83% are obtained by use of one time of roughing, one time of scavenging and two times of cleaning.