Papers by Keyword: Acetonitrile

Abstract: Nanostructured manganese-containing oxide coatings on titanium were formed by method of plasma electrolytic oxidation in tetraborate aqueous electrolyte containing manganese acetate with and without the acetonitrile addition. These oxide layers with high content of manganese and coated by ordered "leaf-like" mesh nanostructures are formed in the electrolyte without acetonitrile addition. The oxide layers are displayed high acitivity towards oxidation CO and photoactivity in the degradation reaction of methylene blue. The addition of acetonitrile into electrolyte results in the change in the morphology of the coating surface, a significant reduction in the manganese content and, as a consequence, practical loss of activity in the oxidation of CO in CO₂ and a reduction in the photocatalytic activity in the decomposition of methylene blue.

Abstract: Ionic Liquids is called also room temperature molten salt, its performance is mainly dependent on composition of cation and anion, and through molecular design the adjustment. And the traditional organic solvent, water, supercritical fluid and chemical reaction than solvent, ionic liquid in the following several aspects to show its prominent advantages. N-heptyl-pyridine tetrafluoroborate is prepared by the double decomposition reaction of HEPB and NaBF4. The ionic liquid at room temperature used in the experiment has a significant absorption determined by UV spectrum within the range of 200-400nm, the maximum absorption wavelength of HEP-BF4 ionic liquid in acetonitrile is 240nm. The standard working curve of HEP-BF4 ionic liquid is y=0.04518+0.03124X (R=0.99963). The linear range of HEP-BF4 ionic liquids in the acetonitrile is 1-75 mg/L. The recovery rate of HEP-BF4 ionic liquid which is between 95.9% and 102%, is measured by standard addition method in acetonitrile.

Abstract: The monomeric coordination compound pentachloro(acetonitrile)niobium(V), [NbCl₅(NCCH₃)], (NCCH₃ = acetonitrile) has been prepared under aerobic conditions and characterized by single-crystal X-ray diffraction. [NbCl₅(NCCH₃)] crystallized in the monoclinic spacegroup P2₁/c with a = 5.964 (3), b = 9.888 (5), c = 15.448 (9) and β = 98.224 (2). Comparison is made to a previously published isomorphous complex that was prepared under unaerobic conditions.

Abstract: In order to research the possibility of separating the azeotrope of ethyl acetate + acetonitrile with ionic liquid as the extractant. Isobaric vapor-liquid equilibria for the ternary system ethyl acetate + acetonitrile + 1-octyl-3-methylimidazolium tetrafluoroborate ([OMIBF₄) were measured at 101.32 kPa using a recirculation still. The results showed that the VLE of the ternary system was different from that of the binary system. The ionic liquid (IL) studied showed a slight crossover salt effect, which changed the relative volatility of ethyl acetate to acetonitrile and eliminated the azeotropic point when the mole fraction of IL in the liquid phase was greater than 0.05. Therefore, [OMIBF₄ can be used as the extractant of extractive distillation for ethyl acetate + acetonitrile system, the suitable mole fraction of [OMIBF₄ is about 10%.

Abstract: In this study, we first purposefully synthesized SAPO-11 and Na-ZSM-23 molecular sieves. The catalysts loaded with Cu were prepared by using seven typical carriers, including Montmorillonite-K10, USY, SAPO-11, Na-ZSM-23, γ-Al₂O₃, ZnO and MgO, and the performance of the catalysts was tested for amination of ethanol. The results demonstrate that the acid-base property of the carriers is closely related with the results of amination of ethanol over the catalysts. Among all these catalysts, 15%Cu/Na-ZSM-23 shows the highest yield of acetonitrile.

Abstract: The procedure is described for the purification of acetonitrile to a level suitable for spectroscopic and chromatographic work. Rectification of chemical pretreated acetonitrile was performed on glass vacuum-jacketed column, filled with spiral-prismatic packing.

Abstract: The paper concentrated on the optimization of the recombinant strain BL21 (DE3)-PE7-Nit. The component of culture medium and the culture conditions were optimized. The optimized medium was: yeast extract 10 g/l, L-glutamate sodium 8 g/l, MgSO4.7H2O 0.7 g/l, Isopropyl-β-D-thiogalactopyranoside 0.3 mmol/L, potassium hydrogen phosphate 0.5 g / L, phosphate Potassium 0.5 g / L and the culture condition was: initial pH 7.0, inoculum 2%. The result showed that the activity of nitrilase prepared with these conditions increased by 130.37 % through optimization.

Abstract: High yield synthesis of bamboo-like multi-walled carbon nanotubes (BCNTs) over a novel zeolite catalyst has been achieved using acetonitrile as a carbon source. The synergism of nickel (Ni) and rare earth oxides (REO) in the zeolites is considered very important for the high activity of the catalysts for the rapid decomposition of acetonitrile and diffusion of carbon. The yield of BCNTs increases with the Ni content and the growth time. The as-grown BCNTs are arranged in the form of flower-like clusters surrounding each zeolite. This CNT-zeolite composite may be regarded as a complex zeolite which will be very useful for the selective absorption, filtration and storage of gas.

Abstract: After the 9∙11 terrorism and America-Iraq war, apprehension of mass destruction weapons such as bio-chemical agents calls for much more sensitive sensors which can detect toxic gases. In this study, semiconductor gas sensors based on tin oxide were examined to detect chemical agent simulants: dimethyl-methyl-phosponate (DMMP), di(propylene glycol) methyl ether (DPGME), acetonitrile, and dichloromethane. DMMP((CH3O)3), DPGME(C7H16O3), acetonitrile(CH3CN), and dichloromethane(CH2Cl2) gases are the simulants of nerve agent-sarin, vesicant agent-HN(N(CH2CH2Cl)3), blood agent-AC(HCN), and choking agent-CG(COCl2) gases, repectively. The SnO2 powder was prepared by a coprecipitation method from the mixture of tin chloride and zinc acetate dihydrate. Zinc oxide was doped into SnO2 from 1 wt% to 4 wt% to improve its reliability and sensitivity. To fabricate a thick film, powders were made into paste with organic binder of ethyl cellulose and screen-printed on the alumina substrate. The phase development and morphology of ZnO-doped SnO2 film were investigated by XRD (X-ray diffraction analysis), BET (surface and pore size analyzer), and SEM (scanning electron microscope). The gas sensing characteristics for target gases were examined with a flow-type measurement system. The concentrations of simulants were controlled from 500 ppb to 1500 ppb, and working temperatures were regulated from 250  to 400 .