Preparation of hierarchical mesoporous Zn/HZSM-5 catalyst and its application in MTG reaction

The hierarchical mesoporous Zn/ZSM-5 zeolite catalyst was prepared by NaOH treatment and Zn impregnation, and its application in the conversion of methanol to gasoline （MTG） was studied. N2 adsorption-desorption results showed that the mesopores with sizes of 2-20 nm in HZ5/0.3AT was formed by 0.3 M NaOH alkali treatment. The zeolite samples after modification were also characterized by XRF, AAS, XRD, SEM and NH3-TPD methods. Zn impregnated catalyst Zn/HZ5/0.3AT exhibited dramatic improvements in catalytic lifetime and liquid hydrocarbons yield. The selectivity of aromatic hydrocarbons was also improved after Zn impregnation. It is suggested that the mesopores of Zn/HZ5/0.3AT enhanced the synergetic effect of Zn species and acid sites and the capability to coke tolerance, which were confirmed by the results of catalytic test and TGA analysis, respectively.

Chiral Separation of Spiro-compounds and Determination Configuration

Chiral spirocyclic compounds have attracted the attention of scholars and scientists owing to their potential applications in the pharmaceutical industry as either active pharmaceutical ingredients, catalysts in synthesizing active enantiomers, or as surface modifiers on silica particles to resolve entantiomers. In this study, five spiro compounds of 3,9-diphenyl-2,4,8,10-tetraoxaspiro[5.5]-undecane（1）, 3,9-（4-methoxyphenyl）-2,4,8,10-tetraoxaspiro [5.5] -undecane（2）, 3,9-（4-methylphenyl）-2,4,8,10-tetraoxaspiro [5.5] -undecane（3）, 4,4＇-（2,4,8,10-tetraoxaspiro[5.5]undecane-3,9-diyl）dibenzoic acid（4） and 3,9-di（4-formyl-phenyl）-2,4,8,10-tetraoxa-spiro[5.5]-undecane（5） were synthesized by grinding pentaerythritol with benzaldehyde, 4-methoxybenzaldehyde, 4-methylbenzaldehyde, 4-carboxybenzaldehyde or terephthalaldehyde monoacetal in the presence of InI3r3 under solvent-free conditions. A normal phase HPLC method was successfully developed to resolve entantiomers of compounds 1--5 on a chiral column. Specific optical rotation of R or S entantiomers（1） was determined and the corresponding configurations were proposed based on Lowe＇s rule.

Extraction of Neodymium by Emulsion-Liquid-Membrane within Hollow-Fiber-contactor and Its Mass Transfer Properties

A non-dispersive extraction technique, using an emulsion liquid membrane within a hollow-fiber-contactor for the extraction and enrichment of Nd^3＋ from the dilute feed aqueous, was applied. The emulsion system is consisted of span80 [ sorbitian monooleate], paraffin oil, D2EHPA [ 2-（ 2-ethylhexyl- phosphonic acid）], kerosene as well as HCl solution. The extraction under various conditions such as the span80 concentrations, the flow rate of aqueous, the extraction time and HCl concentrations in receiving phase were studied. Results show that the lower the flow rates of aqueous are, the higher the extraction percentage and enrichment-fold are, and the extraction percentage increases with the increasing of HCl concentrations. When the initial Nd^3＋ concentration in feed is maintained at 1000 mg· L^-1 and the emulsion is recycled with 70 times by a counter-flow,

Crystal Structure of a Novel Sandwich Inclusion Complex of β-Cyclodextrin with α-Naphthylacetic Acid

A supramolecular inclusion complex between β-cyclodextrin（β-CD） and α-naphthylacetic acid was prepared, and its crystal structure was investigated by single-crystal X-ray crystallography. The complex contains two β-CD molecules, one α-naphthylacetic acid, two ethanols and twenty-eight water molecules in the asymmetric unit, which could be formulated as [（C42H70O35）2·（C12H10O2）·（C2H5OH）2·28H2O]. Two β-CD molecules constitute a dimer by face-to-face contact of their secondary hydroxyl sides. At the interface of the dimer, one α-naphthylacetic acid molecule is sandwiched between two β-CD molecules. Each β-CD unit of the dimer includes one ethanol molecule in its cavity. The β-CD dimers are linked together via hydrogen bonding to form layers that are stacked in a brickwork-like pattern. The comparative study of some sandwich complexes elucidates that the interface of the β-CD dimer has a stronger inclusion capacity than the cavity of β-CD for some suitable planar guest molecules. The novel inclusion structure results from the competitive inclusion of α-naphthylacetic acid and ethanol.

One-pot Synthesis of 2-Nitro-4,5-dicyano-1H-imidazole

In the last few decades,nitroimidazoles have been investigated mostly due to their properties as antibiotics,radiosensitizers and anti-protozoans[1 -3].Recently these nitroimidazoles,such as 2,4-dinitroimidazole,1-methyl-2,4,5-trinitroimidazole and their energetic salts, have attracted renewed attention for their favorable explosive performance as well as improved safety characteristics[4,5].Because of the activity of cyano group,2-nitro-4,5-dicyano-1 H-imidazole (NDCI) could be used as an intermediate in the synthesis of novel energetic materials containing nitroimidazole moiety.NDCI has been synthesized by the procedure given by Yixin Lu and coworkers[6],where the diazotization reaction and the Sandmeyer reaction were separately achieved.NDCI was obtained by adding a solution of sodium nitrite to 2-diazo4,5-dicyanoimidazole which was generated by diazotization of 2-amino-4,5-dicyano-1H-imidazole ( ADCI ) with sodium nitrite in water-hydrochloric acid and collected by filtration.Dry 2-diazo-4,5-dicyanoimidazole was so sensitive to shock that its separation may cause explosion[7].

ADSORPTION BEHAVIOUR OF Mn(Ⅱ) AND Zn(Ⅱ) ON ATTAPULGITE WITH FAAS METHOD

Active attapulbgite as adsorptive reagent, the adsorptive behavior of Mn(II) and Zn(II) was studied with Flame atomic absorption spectroscopy (FAAS) method. The mainly factors of influencing the adsorption and desorption of Mn(II) and Zn(II) were discussed. The interference of coexisting ions was investigated, and the actual sample determination from adzuki beans, mung beans and phosphating waste water was conducted with good result.

STUDY ON DETERMINATION OF TRACE Fe BY Fe(Ⅱ)-VA THIN LAYER RESIN PHASE SPECTROPHOTOMETRY

A new method for the determination of Fe by thin layer resin phase spectrophotometry in alkali condition was reported. The complex anion formed by Fe(II) and VA was absorbed on the 717# resin and Fe was determined by making thin layer. This method had a high sensitivity (ε620= 3.0×105L/mol·cm), which was 15 times higher than that of liquid phase spectrophotometry. It had been proved a satisfactory precision (5.0μg Fe, n=6, RSD=1.8%). The trace Fe in natural water was determined and the recovery was 97%.

Cobalt(Ⅱ) coordination polymers built on isomeric dipyridyl triazole ligands with pyromellitic acid:Synthesis,characterization and their effects on the thermal decomposition of ammonium perchlorate

Three new cobalt(Ⅱ) coordination compounds,[Co(3,3'-Hbpt)2(H2pm)(H2O)2]·2H2O(1),[Co(4,4'-Hbpt)(pm)0.5(H2O)]·3H2O (2) and [Co(3,4'-Hbpt)(pm) 0.5 (H2O)3]·2H2O(3)(3,3'-Hbpt=3,5-bis(3-pyridyl)-1H-1,2,4-triazole;4,4'-bpt=3,5-bis(4-pyridyl)1H-1,2,4-triazole,3,4'-Hbpt=3-(3-pyridyl)-5-(4'-pyridyl)-1H-1,2,4-triazole and H4pm=pyromellitic acid) have been synthesized by hydrothermal reactions.Single-crystal X-ray diffraction reveals that compound 1 has a one-dimensional (1D) chain network,2 exhibits a four-connected three-dimensional (3D) structure with 1D open channels encapsulated by water molecules,while 3 displays a regular two-dimensional (2D) architecture connected through 1D metal helical chains.In addition,the efficacy of compounds 1-3 as additives to promote the thermal decomposition of ammonium perchlorate (AP) is explored by differential scanning calorimetry (DSC).

Syngas production in a novel perovskite membrane reactor with co-feed of CO_2

Partial oxidation of methane（POM） co-fed with CO_2 to syngas in a novel catalytic BaCo_（0.6）Fe_（0.2）Ta_（0.2）O_（3-δ） oxygen permeable membrane reactor was successfully reported.Adding CO_2 to the partial oxidation of methane reaction not only alters the ratio of CO/H_2,but also increases the oxygen permeation flux and CH_4 conversion.Around 96%CH_4 conversion with more than 93%CO_2 conversion and 100%CO selectivity is achieved,which shows an excellent reaction performance.A steady oxygen permeation flux of 15 mL/（cm^2 min） is obtained during the 100-h operation,which shows good stability as well.