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Influence of Fluoride Ions on the Structure-directing Effect of Organic Amine in the Synthesis of aluminophosphate Open-frameworks

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Chemical Research in Chinese Universities 2017年第6期33卷 853-859页

作者： TIAN Ye XU Jun WANG Zi DENG Feng XU Ruren YAN Wenfu State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of Chemistry Jilin University Changchun 130012 P. R. China State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan 430071 P R. China Jilin Province Product Quality Supervision Testing Institute Changchun 130012 P. R. China

The crystallization behavior of the initial mixture with the composition of Al2O3：4.0P2O5：3.0 diethylenetriamine（DETA）：xHF：153H2O was investigated at 180 ℃, where 0≤x≤3. If x≤1.8, three-dimensional openframework aluminophosphate AIPO-CJ31 was obtained. If 2 ≤x≤3, a chain-like aluminophosphate（1） was obtained. The crystallization process of both compounds was investigated by means of powder X-ray diffraction（XRD） and the concentrations of A1 and P in the liquid product during the crystallization process were analysed by means of induc- tively coupled plasma atomic emission spectroscopy（ICP-AES）. The evolution of the coordination state of A1, P and F during the crystallization was monitored with 27A1, 31p and 19F MAS NMR technique. The influence of the fluoride ions and the source of fluoride ions on the structure-directing effect of DETA was discussed. It was found that the fluoride ions changed the crystallization direction of the initial mixture, i.e., the structure-directing effect of DETA, via altering the distribution or micro-structure of the inorganic fragments.

关键词： Zeolite aluminophosphate Open-framework Structure-directing effect Fluoride

Structure-directing Effect on Synthesis of Layered aluminophosphates with Same Topology

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Chemical Research in Chinese Universities 2017年第4期33卷 513-519页

作者： WANG Aitian XU Jun WANG Chao DENG Feng XU Ruren YAN Wenfu State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of Chemistry Jilin University Changehun 130012 P. R. China State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan 430071 P. R. China

Three layered aluminophosphates（UiO-15, APDAP12-150 and APDAP-150） with same topology were crystallized from an initial mixture with a molar Composition of A1203：***2Os：5.5R：227HzO, where R is ethylene- diamine, 1,2-diaminopropane or 1,3-diaminopropane, respectively. The crystallization processes of UiO-15, APDAPI2-150 and APDAP-150 were investigated using solid-state NMR in combination with XRD and other cha- racterization techniques. The evolution of the coordination states of Al and P in the solid products was monitored, and the possible starting points of crystallization（core units） of UiO-15, APDAP12-150 and APDAP-150 were obtained and analyzed. The formation ofa trimer as well as a hexamer of aluminophosphate, a monomer of PO4 and a nonamer containing two three-membered rings is critical for the start of crystallization of UiO-15. The formation of a hexamer and a pentamer is critical for the start of crystallization of APDAP12-150. The formation of an A106 monomer and a pentamer containing a three-membered ring is critical for the start of crystallization ofAPDAP-150. The crystal water played a co-structure-directing role in the formation ofAPDAP-150.

关键词： Zeolite aluminophosphate Templating effect Stnlcture-directing effect

Removal of Low-concentration Ammonia from Ambient Air by aluminophosphates

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Chemical Research in Chinese Universities 2018年第3期34卷 480-484页

作者： LI Chunyang WU Shujie YU Guiyang YANG Xuwei LIU Gang ZHANG Wenxiang Key Laboratory of Surface and Interface Chemistry of Jilin Province College of Chemistry Jilin University Changchun 130021 P. R. China

A series of aluminumphosphate materials was prepared and used as adsorbents for the removal of ammonia at low concentrations. The influence of various preparation parameters, including the pH value of sol, calcination temperature and molar ratio of P/A1, on the structure and surface properties as well as adsorption capacity was investigated. The results showed that large amount of P-OH present on the surface of aluminophosphates was suitable for the removal of ammonia. They were the major source of weak Br6nsted acid sites and acted as the main active centers for capturing ammonia.

关键词： Ammonia adsorption aluminophosphate Air purification Weak acid Porous material

非晶态金属-磷酸铝催化正庚醛和苯甲醛羟醛缩合制茉莉醛(英文)

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催化学报 2015年第2期36卷 209-215页

作者： A. Hamza N. Nagaraju Catalysis Research Laboratory St. Joseph's College P.G. and Research Centre Bangalore 560027 India

Amorphous aluminophosphate(AlP) and metal-aluminophosphates(MAlPs, where M = 2.5 mol%Cu, Zn, Cr, Fe, Ce, or Zr) were prepared by coprecipitation method. Their surface properties and catalytic activity for the synthesis of jasminaldehyde through the aldol condensation of nheptanal and benzaldehyde were investigated. The nitrogen adsorption-desorption isotherms showed that the microporosity exhibited by the aluminophosphate was changed to a mesoporous and macroporous structure which depended on the metal incorporated, with a concomitant change in the surface area. Temperature-programmed desorption of NHand COrevealed that the materials possessed both acidic and basic sites. The acidic strength of the material was either increased or decreased depending on the nature of the metal. The basicity was increased compared to AlP. All the materials were X-ray amorphous and powder X-ray diffraction studies indicated the absence of metal oxide phases. The Fourier transform infrared analysis confirmed the presence of phosphate groups and also the absence of any M-O moieties in the materials. The selected organic reaction occurred only in the presence of the AlP and MAlPs. The selectivity for the jasminaldehyde product was up to 75% with a yield of 65%. The best conversion of nheptanal with a high selectivity to jasminaldehyde was obtained with FeAlP as the catalyst, and this material was characterized to have less weak acid sites and more basic sites.

关键词： Amorphous aluminophosphate Metal-aluminoposphate Surface property Acid-base bi-functional catalyst Aldol condensation Jasminaldehyde

Synthesis of bifunctional Pt/MgAPO-5 catalysts and their catalytic performance in the hydrogenation of nitrobenzene to p-aminophenol

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Science China Chemistry 2010年第7期53卷 1514-1519页

作者： ShuFang Wang YaDan Jin BeiBei He YanJi Wang XinQiang Zhao Hebei Univ Technol Key Lab Green Chem Technol & High Efficient Energ Tianjin 300130 Peoples R China

MgAPO-5 molecular sieves have been synthesized using diethylaminoethanol as the templating agent in a wide range of the MgO/Al2O3 *** samples were characterized by XRD,SEM,solid state NMR,FT-IR and *** MgAPO-5 as acidic supports,bifunctional Pt/MgAPO-5 catalysts were prepared for hydrogenation of nitrobenzene to p-aminophenol (PAP).The results showed that the MgO/Al2O3 ratios influenced the Mg content and the acidity of MgAPO-5 samples,thereby greatly affecting the catalytic performance of Pt/MgAPO-5 *** selectivity to PAP over Pt/MgAPO-5 was dependent on the amount of strong acid sites of *** the MgO/Al2O3 molar ratio was 0.5,the synthesized MgAPO-5 sample exhibited the largest amount of strong acid and a highest PAP yield of 41.1% was achieved over Pt/MgAPO-5 catalyst.

关键词： aluminophosphate molecular sieve bifunctional catalyst p-aminophenol nitrobenzene hydrogenation

Uncovering the Phase Transition of Berlinite (α-AlPO_(4)) under High Pressure:Insights from First-principles Calculations

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Journal of Wuhan University of Technology(Materials Science) 2021年第2期36卷 248-254页

作者： LI Neng HU Hai GUO Fei TAO Haizheng State Key Laboratory of Optical Fiber and Cable Manufacture Technology(Yangtze Optical Fiber and Cable Joint Stock Limited Company) Wuhan 430073China State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070China

We investigated the mechanism of crystalline-to-amorphous phase transition(CAPT)for amorphous berlinite(a-AlPO_(4))under high pressure using ab initio constant-pressure *** results show that the pressure to the change in phase transition takes place at around 20 GPa,which is inconsistent with the previous results of around 15 *** confirm the feasibility of our model,the calculated X-ray powder diffraction for crystal berlinite is concordant with the standard PDF *** assessing a full spectrum of properties including atomic structure,bonding characteristics,electron density of states and real-space pair distribution function at each pressure,we reveal the details of phase ***,all the information from our present results elucidates that Al-O bonds play an irreplaceable role during the process of phase transition to uncover the structural and electronic properties of ***,our work substantiates that it is essential to utilize a wide range of changes in order to provide a comprehensive understanding on the nature of the CAPT in other inorganic oxides.

关键词： aluminophosphate atomic and electronic structures phase transition ab initio calculation

Hydrothermal synthesis of AlPO4-5:Effect of precursor gel preparation on the morphology of crystals

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Progress in Natural Science:Materials International 2012年第6期22卷 684-692页

作者： Dan Li Jianfeng Yao Huanting Wang Department of Chemical Engineering Monash UniversityClaytonVic 3800Australia Environmental Engineering School of Engineering and Information TechnologyMurdoch UniversityMurdochWA 6150Australia

This paper reports on the effect of precursor gel preparation on the microstructural formation of aluminophosphate-5(AlPO4-5) molecular sieves in the hydrothermal *** morphology of AlPO4-5 crystal changed from sphere to ellipse with two symmetrical craters when the aluminophosphate precursor gel was prepared via dropwise addition of acid and TEA under strong stirring,and continuous stirring overnight during the gel aging *** results also showed that both of well-crystallized spherical and elliptical AlPO4-5 crystals covered by the fibrous crystals could be hydrothermaily synthesized at 150℃for 4 h or *** average particle size of spherical AlPO4-5 samples was about 35-45μm in diameter,whereas the elliptical AlPO4-5 exhibited approximately 13μm in width and 15μm in length.

关键词： aluminophosphate AlPO4-5 Stirring Elliptical structure Crater structure

Immobilization of simulated radioactive fluoride waste in phosphate glass

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Science China Materials 2016年第4期59卷 279-286页

作者：孙亚平夏晓彬乔延波包良满马洪军刘学阳钱正华 Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China

Radioactive alkali fluoride salts are generated during the operation of molten salt reactors(MSRs) and reprocessing of their spent fuel, and appear in the formof fluidity granule, or powder. In order to prevent the radionuclides from being released into the environment(especially, via exposure to water), it is necessary to develop a new technology for the temporary storage or final disposal of wastes containing radioactive fluorides. The immobilization of alkali fluoride wastes in phosphate glasses has been proposed. In this study, iron phosphate(IP) glasses and sodium aluminophosphate(NaAlP) glasses were evaluated for the immobilization of simulated radioactive fluoride wastes. IP and NaAlP glass matrixes were mixed with simulated wastes and reacted in air at temperatures in the range of 950–1200°C. A high waste loading was obtained in the experiment. The properties of the waste forms were characterized by X-ray diffraction and Raman spectroscopy. The latter indicated that IP glass contains less Q^2 without Q^3(2 and 3 represent the number of bridging oxygens on a PO_4 tetrahedron), and it is concluded that IP glass is more stable than NaAlP glass. Leaching tests were performed in deionized water by using the product consistency test A(PCT-A method), and the result shows that the leaching resistance of IP waste forms is better than that of NaAlP waste forms. This study demonstrates the potential of IP glass for the stabilization and immobilization of radioactive fluoride wastes from MSRs.

关键词： radioactive waste alkali fluoride iron phosphate glass sodium aluminophosphate glass

Synthesis and Characterization of the Large Pore Molecular Sieves VPI-5 and Si-VPI-5

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Chemical Research in Chinese Universities 1991年第1期7卷 11-17页

作者： Yao Shangqing, Qiu Shilun, Pang Wenqin Yu Long (Department of Chemistry, Jilin University, Changchun)Li Liyun (Wuhan Institute of Physics, Wuhan)Xin Qin (Dalian Institute of Chemical Physics, Dalian)

The large pore molecular sieves VPI-5 and Si VPI-5 were synthesized by using three organic amines (dipropylamine, diisopropylamine and dipentylamine) as the structure-directing agents. Compared with general alumlnophosphate molecular sieves, the synthesis of the molecular sieves of VPI-5 type ls of many unique features. Both VPI-5 and Si-VPI-5 were characterized by XRD, IR, TG-DTA, and MAS-NMR.

关键词： aluminophosphate VPI-5 Molecular sieves