Qiu Shilun

Synthesis and Characterization of Fapo-5 Crystallized From Clear Homogeneous Solutions

Abstract Ferroaluminophosphate number 5 molecular sieve (FAPO-5) was hydrothermally synthesized from clear homogeneous solutions. EPR, Mossbauer, XPS and electron probe microanalysis (EPMA) investigations evidence that iron is only substituted for aluminum but not for phosphorus atoms. The distribution of iron atoms in the sample is rich in the center and both Fe(III) and Fe(II) exist in the FAPO-5 crystals. FAPO-5 exhibits higher catalytic activity and selectivity for the ethylbenzene dehydrogenation, compared to those of AlPO 4 -5 and FAPSO-5.

Crowth of Single Crystals of Borozeosilite and Titanozeosilite

Abstract B-, Ti MFI-type zeolite single crystals known as Borozeosilite and Titanozeosilite were synthesized by hydrothermal crystallization in a non-alkaline medium in the presence of fluoride. The growth of the single crystals was investigated by means of Si NMR and TMS-GC methods. X-ray structure analysis was performed on the crystals, and precise atom positions were determined. The cell parameters are a=19.976, b=19.843, c=13.339 and a=20.046, b=19.950, c=13.405A for Borozeosilite and Titanozeosilite, respectively, which corresponds to isomorphous substitution of silicon by boron or titanium in the zeolite framework.

Synthesis of microporous membranes and films on various substrates by novel electrospinning method

The introduction of electrospinning technique in synthesis of supported microporous membranes and films opens bright prospects for mass production and practical applications. This novel and promising strategy has wide suitable range for various substrates with the possibility of large-area processing. We successfully synthesized several kinds of microporous materials into high quality membranes and films on different shaped supports by this method, such as zeolite NaA and pure-silica-zeolite Beta membranes on porous Al2O3 tube, zeolite NaY membrane on stainless steel net and a metal-organic framework Eu(BTC)(H2O)·DMF (JUC-32) film on porous silica disc. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used as characterization means. The results verified the effectiveness of this new approach in fabrication of membranes and films.

Synthesis of large single crystals of pentasil-type silica zeolites from non-alkaline medium

Large single crystals of pentasil-type silica zeolites (Silicalite-I and ZSM-39) have been synthesized with choline cation, 1,4-diazabicyclo[2.2.2]octane, and tetramethylammonium cation as templates from non-alkaline medium.

Luminescent properties of RE-silicalite-I and RE-ZSM-5 zeolites synthesized by direct hydrothermal crystallization

Rare earth ions were introduced into silicalite-I and ZSM-5 by direct hydrothermal crystallization either in a non-alkaline aqueous medium containing fluoride or in an alkaline medium. The excitation and emission spectra of europium, cerium and terbium ions in the zeolites were investigated.

ZEOLITES SYNTHESIZED FROM NONALKALINE MEDIA

ABSTRACT Hydrothermal crystallization of zeolites and clathrass, at 100~200°C from non-alkaline media containing F– anions and organic template has been investigated. Under such conditions Zeolite P, ZSM-39, Theta-1, ZSM-5, a novel zeolite (CJS-1) and two novel clathrasils(CJS-2 and CJS-3) could be prepared. The conditions and various effects on the synthesis were systematically investigated. The large single crystals of Zeolite P, ZSM-39, CJS-2 and CJS-3 were obtained. The ZSM-5 single crystals were synthesized using seven kinds of organic amines.

A stable ZIF-8-coated mesh membrane with micro-/nano architectures produced by a facile fabrication method for high-efficiency oil-water separation

With the possibility of large-area processing, the ZIF-8-coated mesh membranes with rough micro-/nanostructures and underwater superoleophobic properties were successfully fabricated at ambient temperature and pressure. These membranes exhibited excellent separation efficiency over 99.99% for various oil-water mixtures with the residual oil content in the collected water less than 4 ppm, and high water flux of 10.2×104 L m−2 h−1. Furthermore, the ZIF-8-coated mesh membrane displayed outstanding stability towards high temperature and various organic solvents immersion. More importantly, based on its facile fabrication method, this kind of ZIF-8-coated mesh membrane can be easily enlarged, which is critical for the practical oil-water separation applications.摘要在常温常压条件下, 以金属网为载体, 成功地制备出表面具有微纳结构的ZIF-8分离膜, 该膜显示出优异的水下超疏油性能. 该方法制备的ZIF-8分离膜, 可以高效地分离多种油水混合物, 油水分离效率高达99.99%, 同时具有较高的水通量10.2×104 L m−2 h−1, 以及耐压性. 进一步, 通过高温处理以及多种常见有机溶剂浸泡, 该膜仍然可以保持高效的油水分离性能, 并且可以循环使用. 由于制备方法简单, 该类ZIF-8油水分离膜可以实现大面积制备, 这对于油水分离的实际应用至关重要.

Sustainable Synthesis of Hierarchically Porous Silicalite-1 Zeolite by Steam-assisted Crystallization of Solid Raw Materials Without Secondary Templates

Hierarchical silicalite-1 zeolites were obtained from the direct conversion of a mixture of ground solid raw materials via a steam-assisted crystallization(SAC) method without involvement of any mesoscale template. Only a trace amount of water was necessary during the crystallization, implying that the amount of water can be dramatically reduced, which still offers easy separation and high yields. The simple procedure involved only grinding and heating, which not only saves resources and energy, but also significantly reduces the discharge of eco-friendly synthesis of zeolites for practical applications. Compared to conventional bulk silicalite-1, the nanosized hierarchical zeolites with MFI structure show enhanced removal capabilities for methylene blue owing to their hierarchical porosity.

Synthesis and Visible-light Photocatalytic Performance of C-doped Nb 2 O 5 with High Surface Area

C-doped Nb2O5 with abundant mesopores has been successfully synthesized through a facile solvothermal synthetic strategy followed by calcination treatment. The resulting C-doped Nb2O5 displayed the highest BET surface area(345 m2/g) and large mesopore size(ca. 4.2 nm), capable of offering more accessible active sites as well as faster mass transfer for catalysis. Besides, the doping of C(2.21%, molar fraction) at the O sites in Nb2O5 lattice greatly enhanced visible-light response by lowering the band gap, thereby making the material a photocatalyst under visible-light irradiation. Typically, the C-doped Nb2O5 exhibited a high H2 evolution rate of ca. 39.10 μmol·g–1·h–1 and also degraded RhB dye completely after 30 min of visible light exposure, which turned out to be much better than Degussa P25 and pure Nb2O5 catalysts.

Synthesis and Gas Storage of Porous Poly(phenyl ether)

A poly(phenyl ether), JUC-Z6, with dia-c5 topology was designed and synthesized with cheap reactants tetrakis(4-bromophenyl) methane and hydroquinone via Goldberg modified Ullmann biaryl ether condensation reaction. JUC-Z6 was determined by MAS NMR, FTIR, SEM, TEM and PXRD. The functional structure exhibits not only high thermal stability(214 degrees C) and high chemical stability, but also large surface area(191 m(2)/g), and the pore size is 1.36 nm. Low pressure gas uptake experiments on activated JUC-Z6 show high heat of sorption(Q(st)=4.1 kJ/mol for hydrogen, Q(st)=33.7 kJ/mol for carbon dioxide and Q(st)=4.1 kJ/mol for methane) among porous materials.